Chẩn Đoán Và Điều Trị Phẫu Thuật Tái Tạo Hiện Đại (CURRENT Reconstructive Surgery)

PHYSICAL AND RADIOLOGIC EVALUATION OF THE HAND • 583
and fl exor digitorum profundus (FDP) of the ring and
small fi ngers. Seventy-fi ve percent of the population has
dual innervation (median and ulnar) to the long fi nger
FDP. 2 The dorsal sensory branch exists 8 cm proximal
to the wrist crease. After the ulnar nerve passes through
Guyon canal, the deep branch innervates the hypothenar
muscles, the interosseous muscles, the small and ring
fi nger lumbrical muscles, the adductor pollicus, and the
deep head of the fl exor pollicus brevis (the superfi cial
head is innervated by the median nerve). An ulnar nerve
injury will result in weakness of the above muscles.
Acutely, the patient will demonstrate a Wartenburg sign
(paradoxical abduction of the small fi nger keyed to the
unopposed pull of the extensor digiti quinti, or EDQ),
and a Froment sign (fl exion of the thumb interphalangeal
[IP] joint due to substitution by the fl exor pollicus longus
[FPL] during key pinch in the presence of a paralyzed
adductor pollicus). In a low ulnar nerve injury, clawing
will develop because of the loss of the balancing effect
of the lumbrical muscles, resulting in the unopposed
pull of the extensor tendons which hyperextend the
metacarpophalangeal (MCP) joint and the fl exor tendons
which hyperfl ex the IP joints. Clawing does not occur in
a high ulnar nerve injury due to paralysis of the long
fl exor tendons.
Median Nerve. The median nerve sequentially inner-
vates the palmaris longus, the fl exor carpi radialis (FCR),
and the fl exor digitorum superfi cialis (FDS) before
entering and innervating the pronator teres. The median
nerve then gives off the anterior interosseous nerve
branch, which continues distally to innervate the FDP
for the index and middle fi ngers, the FPL, and the prona-
tor quadratus. The median nerve travels superfi cially
in the distal forearm giving off the palmar cutaneous
branch 5 cm proximal to the wrist crease. In the wrist,
the recurrent motor branch innervates the thenar mus-
culature. Motor branches to the lumbrical muscles to the
index and middle fi ngers arise distal to this. Take note
that an anterior interosseous nerve injury will result only
in motor defi cits resulting paralysis of the profundus
tendon to the index and the FPL, easily demonstrated
by inability to gesture OK. A complete median nerve
injury will result in weakness of some or all the above
listed muscles, which can be tested individually (see next
section). When asked to make a fi st, patients with high
median nerve injuries will form a Benedictine or papal
sign (extended thumb and index fi nger).
Radial Nerve. The radial nerve passes over the lateral
humeral epicondyle with the profunda brachii artery
and its radial collateral branch. It innervates the brachio-
radialis and the extensor carpi radialis longus (ECRL)
before dividing into the superfi cial (sensory) and the
deep (motor) branches. The deep branch innervates
the extensor carpi radialis brevis then passes through
and innervates the supinator, emerging as the posterior
interosseous nerve (PIN). The PIN immediately inner-
vates the extensor carpi ulnaris (ECU), then continues
down the forearm innervating the extensor digitorum
communis (EDC), the EDQ, the abductor pollicus longus
(APL), the extensor pollicis brevis (EPB), the extensor
pollicis longus (EPL), and the extensor indicis proprius
(EIP). The radial nerve and the posterior interosseous
nerve, are responsible for wrist and MCP extension,
and can be quickly and easily assessed by testing these
functions. The inability to extend either the wrist or the
MCP joints should raise suspicions of a radial nerve/PIN
injury. Remember that the ulnar innervated intrinsic
muscles of the hand can provide extension of the fi ngers
at the IP joints, especially when the MCP joint is held in
extension.
MUSCULOTENDINOUS UNITS
Each muscle of the arm and hand can be individually
tested. This can provide insight into the function and
integrity of each specifi c muscle, its tendon, as well as to
confi rm the adequacy of its innervation. In the following
section, the specifi c testing maneuvers will be discussed for
each muscle.
FIGURE 49-3. Tenodesis effect on fi nger cascade. (A)
Passive extension of the wrist. (B) Passive fl exion of the wrist.
B
A

584 • CHAPTER 49
Dorsal Forearm and Hand
The extensor carpi radialis brevis functions is one of the
primary wrist extensors. Since it inserts into the base of
the third metacarpal, its function is tested by having the
patient forcefully extend their wrist with their fi ngers
slightly fl exed, while the examiner’s hand rests lightly over
the index and long metacarpals. Remember that other
muscles can act to extend the wrist, such as the ECRL
and ECU. However, if the ECRL or ECU were the only
muscle participating in wrist extension, the hand would
also radially or ulnarly deviate, respectively. The fi ngers
and thumb are lightly curled to eliminate the possible
weak participation by the EDC, EIP, EDQ, and EPL.
The APL and EPB tendons form the volar border of the
anatomic snuff box. The tendon of the APL can be eas-
ily palpated while having the patient forcefully abduct the
thumb metacarpal in the frontal plane. The EPB is tested
by having the patient put their palms and thumbs together
and abduct the thumbs away from the hand while main-
taining contact.
The EPL tendon forms the dorsal aspect of the anatomic
snuff box and is tested by having the patient forcefully
extend the thumb IP joint against resistance. Alternatively,
the EPL can be tested by having the patient rest their palm
fl at and attempt to lift the entire fi rst ray off the examina-
tion table (ie, thumb retropulsion).
The EDC travels across the dorsal aspect of the hand
to all of the fi ngers, except the fi fth which may be absent
in 29% to 60%. The EDC has a common muscle belly
and its function can be evaluated by having the patient
extend their MCP joints against resistance or extend the
IP joints with the MCP joints fl exed. When evaluating
the EDC for possible injury (such as in a dorsal hand lac-
eration), one should have a high degree of suspicion for
occult EDC transections. Proximal injuries can be easily
missed due to the pull from the adjacent junctura ten-
dinae; even if the EDC to the long fi nger is completely
transected, the patient may be able to weakly extend the
fi nger due to the action of the juncturae from the index
and ring. In addition, independent MCP extension can be
accomplished via the EIP and EDQ in the index and small
fi ngers, respectively. During exploration and/or repair, the
EIP and EDQ are usually found ulnar to their respective
fi nger’s EDC tendon at the distal extensor retinaculum
and at the MCP joint. 3
Another reason to have a high index of suspicion for
tendon injury in dorsal hand wounds is because the soft
tissue of the dorsum of the hand is very thin, making the
extensor tendons more susceptible to injury. If the MCP
is being extended by an adjacent junctura, it is usually a
weaker extension than in the uninjured digits. In addition,
the patient will often complain of pain while attempt-
ing this maneuver. If there is any question as to the status
of the tendons in this circumstance, the best thing to do is
to explore the wound.
The EIP can be selectively tested by having the patient
forcefully extend the index MCP joint while keeping the
remainder of the fi ngers fl exed. By fl exing the other fi n-
gers, the EDC is eliminated from participating in index
fi nger MCP joint extension. Similarly, the EDQ can also be
selectively tested by having the patient forcefully extend
the MCP joint of the small fi nger while keeping the other
fi ngers fl exed into a fi st.
The ECU functions as both a wrist extensor and an
ulnar deviator, and can be selectively isolated by having
the patient forcefully extend and ulnarly deviate their
wrist. The examiner can palpate the tendon just distal to
the ulna on the dorsal-ulnar aspect of the wrist during this
maneuver.
Volar Forearm and Hand
The pronator teres functions to both pronate the forearm
and fl ex the elbow, and can be tested by extending the
elbow and having the patient forcefully pronate their fore-
arm. By extending the arm at the elbow, the muscle is put
on maximal stretch, giving it a mechanical advantage over
the pronator quadratus, which also functions to pronate
the arm. However, pronation could be achieved through
function of the pronator quadratus in this position; it is dif-
fi cult to completely isolate the pronator teres while testing
its function.
The pronator quadratus can be selectively isolated by
fl exing the elbow and then asking the patient to force-
fully pronate their arm. By fl exing the elbow, the examiner
eliminates participation from the pronator teres by placing
it at a mechanical disadvantage.
The FCR and FCU are the primary fl exors of the wrist.
The FCR tendon can be palpated immediately radial to
the palmaris longus tendon (if present) with forceful
fl exion of the wrist with the fi ngers cupped. The palmaris
longus tendon (which can act as a weak wrist fl exor) can
also be palpated with the same maneuver, although it may
be absent in up to 20% of patients. Palpation of the pal-
maris longus tendon may be more obvious if the patient
opposes the thumb to the small fi nger during wrist fl ex-
ion ( Figure 49-4 ). The FCU can be easily palpated at the
volar wrist by asking the patient to fl ex and ulnarly devi-
ate their wrist.
The FDS deserves special consideration in examina-
tion of the hand. Having the patient simply fl ex their fi n-
gers does not rule out injuries to the superfi cialis, since
this action could also be performed by the FDP. To spe-
cifi cally isolate the FDS (which fl exes the middle pha-
lanx), the adjacent fi ngers are held in full extension by
the examiner, and the patient is asked to fl ex the fi nger in
question ( Figure 49-5 ). This maneuver prevents the FDP
from fl exing the fi nger and isolates the FDS for evalua-
tion. The FDS of each fi nger has its own muscle belly
and fl exes independently. The FDP is blocked because
it has a common muscle belly, eg, the FDP of one fi n-
ger cannot function independently of the other fi ngers.
The exception to the rule is that in 85% of patients the
FDP to the index will have independent motion and may

PHYSICAL AND RADIOLOGIC EVALUATION OF THE HAND • 585
mask a FDS injury. If suspected, wiggle the distal pha-
lanx during this test as its motion should be supple.
To further confuse the examiner, there are many anom-
alous nerve and tendon connections between the small and
ring fi nger FDS muscles. Using the above examination to
test the FDS to the small fi nger, approximately 34% of the
population will be unable to fl ex the proximal interphalan-
geal (PIP) joint. If only the index and long fi nger are held
in extension, approximately 16% of the population will
be unable to fl ex the small fi nger PIP joint. Thus, approxi-
mately 16% of the normal population does not have a FDS
to the fi fth fi nger. 4
The FDP of each digit can be tested by asking the
patient to fl ex their distal interphalangeal joint with
the middle phalanx held in extension by the examiner.
Similarly, the FPL can be evaluated by having the patient
fl ex the thumb IP joint against resistance. In 15% of
the normal population, the FPL and index fi nger FDP
will have simultaneous contraction, referred to as the
Linburg-Comstock sign due to tendinous interconnec-
tions. An interesting examination fi nding will occur if
the FDP is lacerated distal to the lumbrical origin. When
asked to make a fi st the FDP tendon will pull strongly on
the lumbrical origin, which will cause MCP joint fl exion
and paradoxical IP joint extension which is known as a
quadrigia effect ( Figure 49-6 ).
The thenar musculature (abductor pollicis brevis,
opponens pollicis, and fl exor pollicis brevis) can be tested
by having the patient forcefully abduct the thumb from
FIGURE 49-4. The palmaris longus tendon is tested by
actively fl exing the wrist with common pinch of all fi ngers to
the thumb.
FIGURE 49-5. The fl exor digitorum superfi cialis is
tested by extending the adjacent digits and asking the
patient to fl ex the fi nger being examined.
FIGURE 49-6. If the profundus tendon is lacerated distal
to the lumbrical origin, MCP joint fl exion and paradoxical IP
joint extension can be seen when the patient is asked to make
a fi st.

586 • CHAPTER 49
the plane of the palm (ie, abductor pollicis brevis action)
and pronate it across to oppose to the small fi nger or the
examiner’s fi nger (opponens) or fl ex at the MCP joint
(fl exor pollicis brevis). The adductor pollicis can be
tested by having the patient forcefully bring the thumb
adjacent to the index fi nger, although the Frohman test is
more reliable.
The volar interossei muscles can be tested by hav-
ing the patient forcefully adduct their fi ngers. By plac-
ing your fi ngers between the patient’s, the examiner can
gauge the strength of the adduction. The dorsal interos-
sei can be tested by having the patient forcefully abduct
their fi ngers.
RADIOLOGIC EXAMINATION
Introduction
Acute osseous trauma of the phalanges and metacarpals
are seen most frequently in young men, but is still the most
common fracture in any age, sex, or ethnicity. 5 When eval-
uating a hand injury, the diagnosis can usually be obtained
with history and physical examination alone. However, in
any setting, other than simple lacerations, there should be
a low threshold for obtaining a standard three-view radio-
graphic examination.
The nature of the fracture pattern is determined by
the direction and the degree of the force applied, whereas
the displacement or angulation of the fracture segments
are the result of deforming forces from intrinsic or extrin-
sic musculotendinous units. Transverse fractures result
from forces perpendicular to the long axis of the bone
or three-point bending loads. Axial loading produces
oblique fractures, the degree of which is directly related
to the magnitude of axial strain. Spiral fractures result
from axial loading with rotational stress. The major-
ity of proximal phalanx fractures have volar angulation,
whereas metacarpal fractures are dorsally angulated. This
results from to the strong pull of the intrinsic muscles,
not the injuring force.
Classifi cation
Fractures in the hand can be classifi ed by multiple means:
location, articular involvement, angulation, displacement,
and nature (greenstick, transverse, oblique, spiral, or com-
minuted). The most important distinction for treatment
in the proximal and middle phalanges is articular involve-
ment. Metacarpal fractures, alternatively, are best subdi-
vided for management by anatomic location and digit
involved.
Imaging
Standard three-view radiographs include posteroan-
terior, lateral, and oblique views. This series is usually
suffi cient to diagnose most fractures and dislocations of
the metacarpal and phalangeal bones. It is often helpful
with isolated digital injuries to obtain three views of the
involved digit alone.
The posteroanterior view is perhaps the most useful
view. It should be read in a systematic fashion, much like
the physical examination. One approach is to start at the
top, checking the phalanges, then the metacarpals, and so
on. Check the edges of the bone, making sure the corti-
cal edges are smooth. Any sharp defects are indicative of
fracture. Also, confi rm that the joint spaces appear roughly
equal in size. This view is particularly helpful in the evalu-
ation of the bases of the metacarpals and proximal pha-
langes. The bases of the second through fi fth MCP joints
should form an M confi guration, the loss of which implies
dislocation.
The lateral view is obtained with the fi fth ray adjacent
to the cassette. Superimposition can be minimized by fan-
ning the fi ngers. This view is important in classifying the
angulation or rotational displacement of fractures and
diagnosing dislocations. The oblique view is taken with the
hand rotated 45 degrees, or half-way between the previous
views. This view allows for good visualization of the fi rst
and second MCP joints.
Additional Imaging/Special Views
An oblique view of the thumb is obtained through the
posteroanterior view of the hand. A true posteroanterior
view of the thumb, called a Roberts view ( Figure 49-7A ),
is preferable when a thumb fracture is suspected. This
is performed by hyperpronating the forearm and plac-
ing the back of the thumb against the x-ray cassette. 6
A Brewerton view ( Figure 49-7 B) is rarely necessary,
but can be helpful in visualizing the metacarpal heads,
hook of the hamate and the fourth and fi fth carpometa-
carpal (CMC) joints. The Brewerton view may also show
erosions of the metacarpal heads and the bases of the
phalanges. The hand is in the anteroposterior position
with the palm facing upward. The MCP joints are fl exed
to 45 degrees with the phalanges in contact with the
fi lm. The tube is angled 20 degrees from the ulnar side
to the head of the third metacarpal. 7 Computed tomog-
raphy, magnetic resonance imaging, three-phase bone
scans, and ultrasound are rarely necessary in the acute
setting.
OSSEOUS INJURIES
Metacarpal Fractures
Intra-articular fractures of the fi rst metacarpal base com-
monly occur in two patterns: the Bennett fracture and
Rolando fracture ( Figure 49-8A,B ). The Bennett fractures
make up approximately one third of all fractures involving
the thumb. They are characterized by an oblique fracture
line at the base of the metacarpal with the proximal-ulnar
fragment (smaller fragment) held on the trapezium by the

PHYSICAL AND RADIOLOGIC EVALUATION OF THE HAND • 587
volar oblique ligament or “beak ligament” and the distal-
radial fragment (majority of the metacarpal) pulled proxi-
mally and radially by the force of the APL. The Rolando
fracture is much less common. It is characterized by a Y- or
T-shaped fracture-dislocation of the base of the fi rst meta-
carpal. The extrinsic muscle forces typically displace the
distal metacarpal fragment dorsally. Extra-articular frac-
tures comprise the approximately 35% of fi rst metacarpal
bone fractures.
Metacarpals 2 to 5 can be subdivided based on the rela-
tive stability of the respective CMC joints. The index and
long CMC joints are relatively motionless and an extensor
lag will develop with very little angulation as opposed to
the more ulnar CMC joints.
A fracture of the metacarpal neck is the most common
fracture of the metacarpal bones. It usually involves the
fi fth and occasionally the fourth metacarpals and is char-
acterized by a transverse fracture with volar angulation.
A fi fth metacarpal neck fracture, or so-called boxer’s frac-
ture, is most commonly caused by striking an object with
a closed fi st.
Fractures of the metacarpal midshaft and base are less
common than neck fractures. Midshaft oblique and spi-
ral fractures can be associated with shortening and a loss
of the knuckle prominence. Small rotational deformities
in the metacarpal shaft will rotate the orientation of the
MCP joint and can cause signifi cant fi nger scissoring with
fl exion. Only 5 degrees of rotational deformity will result
in nearly 1.5 cm of fi ngertip overlap. 8
Basilar fractures are rare, except with the fi fth meta-
carpal. The “baby Bennett” or “reverse Bennett” fracture is
characterized by an oblique intra-articular fracture with
proximal and ulnar displacement of the distal metacar-
pal fragment ( Figure 49-9 ). As in a Bennett fracture, the
displacement is due to the strong pull of the extrinsic
muscles.
FIGURE 49-7. Commonly used additional hand plain
fi lms. (A) Roberts view. (B) Brewerton view.
A
B

588 • CHAPTER 49
Proximal Phalanx Fractures
Fractures of the proximal phalanx should be considered by
location: base, midshaft, and head. Oblique intra- articular
fractures should inspire further physical examination
to ensure the associated collateral ligament is intact.
Oblique and spiral midshaft fractures are commonly asso-
ciated with shortening or rotation, although the rotational
deformity will not produce fi nger tip overlap or scissor-
ing to the same extent as metacarpal fractures. Transverse
fractures can be relatively stable, but often volar angula-
tion will be seen due to the pull of the intrinsic muscles
on the proximal segment. Fractures of the head of the
proximal phalanx can range from small chip fractures to
complete involvement of one or both condyles.
Middle Phalanx Fractures
The incidence of middle phalanx is similar to that of
proximal phalanx fractures. The classifi cation of these
fractures can be thought of in the same ways as the
proximal phalanx. Little angulation is tolerated due to
impingement of the fl exor sheath volarly and the rela-
tively fi xed length of the extensor mechanism from the
insertion on the middle phalanx to the insertion on the
distal phalanx.
Distal Phalanx Fractures
Distal phalanx fractures are usually the result of crush
injuries. Soft tissue injury to the nail bed is commonly
associated with subungual hematoma (usually involving
.80% of the nail bed). Nonarticular and tuft fractures are
usually comminuted, but minimally displaced. Fractures
at the base of the distal phalanx are complicated by the
forces exerted from the terminal tendon dorsally and the
FDP volarly. A mallet fracture is an oblique fracture of
the dorsal cortex, including the terminal tendon inser-
tion. A “jersey fi nger” is an FDP tendon avulsion. The
avulsed FDP tendon is occasionally associated with a
bone fragment. Depending on the fragment size the frag-
ment can become lodged at the distal edge of the A2 or
A4 pulley.
FIGURE 49-8. Fracture dislocation of thumb proximal
phalanx. (A) Bennett fracture. (B) Rolando fracture.
A
B

PHYSICAL AND RADIOLOGIC EVALUATION OF THE HAND • 589
LIGAMENTOUS INJURIES
Thumb
Because of the physical differences in the joints and sup-
porting ligaments, the thumb and fi ngers will be again dis-
cussed separately. Pure dislocation of the basal or CMC
joint of the thumb is rare. The joint stability results from
the strong volar oblique ligament. Dislocation forces on
the thumb CMC joint will result in the Bennett fracture-
dislocation as previously described.
Pure dislocations at the MCP joint of the thumb can
occur, but are quite rare. These dislocations are dorsal and
include injury to the volar plate. The extent of the injury
is variable depending on the extent of accessory and true
collateral ligament damage. In its most severe form, the
proximal phalanx lies dorsal and parallel to the metacar-
pal, the so-called bayonet deformity.
Ulnar collateral ligament damage at the thumb MCP,
the so-called skier’s or gamekeeper’s thumb, is relatively
common. It is diagnosed when there is greater than
40 degrees of MCP joint instability while applying a radial
FIGURE 49-9. Fracture-dislocation of the fi fth
metacarpal base, a “reversed” Bennett fracture.
FIGURE 49-10. Gamekeeper’s thumb with chip fracture
off the proximal phalanx base (top arrow), demonstrating a
Stener lesion (bottom arrow).
stress to the proximal phalanx, or 20% or more angula-
tion than the unaffected thumb. A Stener lesion is a name
that has been applied to the ruptured proximal portion of
the ulnar collateral ligament that has displaced dorsal to
the adductor aponeurosis. 9 Stener lesions can be caused
by excessive ulnar angulation of the thumb MCP joint
during the injury or by the overzealous examining physi-
cian. This can occasionally be detected on radiographs if
a bone fragment is associated with the avulsed ligament
( Figure 49-10 ).
Dislocations at the thumb IP joint are incredibly rare
because the simple hinge joint is quite resistant to radial or
ulnar stress. Dislocations are dorsal and the torn volar plate
usually remains attached distantly and does not impair
reduction.
Fingers—Metacarpophalangeal Joint
Metacarpophalangeal joints in the fi ngers can be either
subluxed or truly dislocated. In subluxations, the joint is
hyperextended 60 to 90 degrees and easily reducible.
Subluxations are more likely in the middle and ring fi ngers,
whereas true dislocations are more common in the index
fi nger and to a lesser degree the small fi nger. 10 True dislo-
cations are usually dorsal and closed reduction is nearly
impossible.
When the index fi nger proximal phalanx dislocates
dorsally, it slides proximally on the metacarpal head. The
fl exor tendons wrap around the ulnar neck and the lumbri-
cal tendon wraps around the radial neck of the metacarpal.

590 • CHAPTER 49
This effectively creates a “noose” that will tighten with
attempted reduction. In the small fi nger a similar “noose” is
formed by the abductor digiti quinti ulnarly and the fl exor
tendons radially. Volar dislocations are rare, but equally dif-
fi cult to reduce in a closed fashion. However, volar disloca-
tions are made irreducible due to the interposition of the
dorsal capsule.
Isolated injuries to the MCP joint collateral liga-
ment complex of the fi ngers will present as swelling and
pain around the affected joint. The radiographic examina-
tion will be normal. A radial collateral ligament injury of
the small fi nger is a more severe injury and will be unsta-
ble due to the pull from the abductor digiti minimi.
Fingers—Proximal Interphalangeal Joint
The collateral ligaments, volar plate, and extensor mech-
anism encircle the PIP joint. For a signifi cant dislocation
to occur, at least two of these structures must be dis-
rupted. Dorsal dislocations are the most common and are
characterized by both volar plate and collateral ligament
disruption. Frequently, the volar plate will be connected to
a bone fragment from the middle phalanx base. Multiple
fracture-dislocation grading systems, ie, Hastings, have
been created based on the joint stability and size of the
bone fragment (percentage of fractured joint surface). 11
For fragments less than 30% of the joint surface, a stable
closed reduction is usually possible. For larger fragments or
unstable joints, an open reduction is usually necessary.
Volar dislocations of the PIP joint are notoriously dif-
fi cult to reduce. The head of the proximal phalanx will
become entrapped between the central slip and lateral band
of the extensor mechanism. Finger traction will tighten the
extensor tendon, making attempted closed reduction dif-
fi cult if not impossible.
Owing to the support of the strong collateral ligaments,
FDP, and terminal tendon insertions, distal interphalangeal
dislocations are rare. Dislocations at this joint are usually
caused by open lacerations of one or more of the support-
ing structures.
1. Gelberman RH, Blasingame JP. The timed Allen test.
J Trauma . 1981;21(6):477–479.
2. Bhadra N, Keith MW, Peckham PH. Variations in innerva-
tion of the fl exor digitorum profundus muscle. J Hand Surg
Am . 1999;24(4):700–703.
3. Celik S, Bilge O, Pinar Y, Govsa F. The anatomical variations
of the extensor tendons to the dorsum of the hand. Clin
Anat . 2008;21(7):652–659.
4. Tan JS, Oh L, Louis DS. Variations of the fl exor digitorum
superfi cialis as determined by an expanded clinical examina-
tion. J Hand Surg . 2009;34(5):900–906.
5. Hove LM. Fractures of the hand. Distribution and relative
incidence. Scand J Plast Reconstr Surg Hand Surg . 1993;
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6. Robert P. Bulletins et mémoires de la société de radiologie de
médicale de France. 1936;24:687.
7. Lane CS. Detecting occult fractures of the metacarpal
head: the Brewerton view. J Hand Surg Am. 1977;2(2):
131–133.
8. Manktelow RT, Mahoney JL. Step osteotomy: a precise
rotation osteotomy to correct scissoring deformities of the
fi ngers. Plast Reconstr Surg . 1981;68(4):571–576.
9. Stener B. Displacement of the ruptured ulnar collateral liga-
ment of the metacarpophalangeal joint. J Bone Joint Surg
Am . 1962;44B(4):869–879.
10. Calfee RP, Sommerkamp TG. Fracture-dislocation about
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REFERENCES

c h a p t e r50
Soft Tissue Reconstruction
of the Upper Extremities
Elvin G. Zook, MD / Srdjan A. Ostric, MD
PATIENT EVALUATION AND SELECTION
Conditions affecting the nail bed can be categorized
within the three major categories of trauma, infection,
and tumors. Nail bed trauma is by far the most common
of these conditions, and to some extent, because of a lack
of knowledge in this subject by many practitioners, treat-
ment of secondary deformities of the fi ngertip is also
common. In all cases, proper treatment of the fi ngertip
and nail bed is predicated on a complete understanding
of the anatomy.
The fi ngertip is defi ned as the portion distal to the
insertion of the fl exor and extensor tendons on the dis-
tal phalanx. The perionychium includes the nail fold,
nail bed, and nail plate, and is unique to primates. All the
components of the hand are present in this compact area,
including fl exor and extensor tendon insertions, nerve,
vessels, and bone ( Figure 50-1 ).
The nail, a complex structure with many functional
roles, helps stabilize the fi ngertip during pinch and
allows one to interface with the world. Without a nail
plate, two-point discrimination increases by a factor
of 2. In addition, there is a high number of immunologi-
cal factors concentrated in the hyponychium.
In evaluating an acute nail bed injury, it is important
to establish the nature of the injury (eg, crush, laceration,
avulsion). It is equally important to obtain a complete his-
tory and physical examination, with particular focus on
factors such as age, hand dominance, general health of the
patient, and the nature of the patient’s employment, as
all these factors will guide the selection of a particular
treatment.
A complete examination of the injury is necessary to
determine whether the nail plate should be removed.
It is clear that when the nail plate is fractured or avulsed,
there is often a nail bed laceration which must be
repaired. A fracture of the tuft or bending of the nail
plate may injure the nail bed, but may not overcome the
force needed to break the nail plate. In general, a fracture
of the tuft is associated with a nail bed injury and the
nail plate will have to be removed. If there is no tuft frac-
ture, it has been our experience that a subungual hema-
toma of greater than 50% requires a removal of the nail
plate, inspection, and repair of the nail bed. If less than
50%, the subungual hematoma may be drained with the
disposable cautery devices in the emergency room (ER)
or a heated paperclip at home.
PATIENT PREPARATION
Preparing a fi ngertip for surgical intervention, whether
it is for tumor, trauma, or infection, is guided by stan-
dard principles. Oftentimes, except in the case of small
children, nail bed injuries are addressed within an ER
setting. In most cases, the whole hand or arm should be
prepped to allow the surgeon sterile access either to the
volar or dorsal surface.
The fi nger is anesthetized by performing a digital
nerve block with 1% lidocaine. Several reports have
discussed the utility and the safety of a solution with
epinephrine, as it can aid with hemostasis and lengthen
the duration of analgesia; however, if the patient has a
risk of vascular compromise, plain lidocaine will suffi ce.
A fl exor tendon sheath block can be delivered intrathe-
cally with an injection just proximal to the A1 pulley
in the palm, but this can be quite painful, especially if
the patient has not received sedation. In this case, we

592 • CHAPTER 50
Paronychium
Nail fold
Nail wall
Eponychial fold
Lunula
Nail plate
Ventral floor
FIGURE 50-1. Germinal matrix where nail production begins. Sterile matrix has
been referred to as the road bed for the nail. The nail plate is not adherent to the nail at
a point distal to the sterile matrix, therefore, disruption of the sterile matrix, or improper
treatment may result in nonadherence of the nail plate. Eponychium is in the dorsal roof
covering for the germinal matrix. Hyponychium refers to the area where the nail separates
from the nail bed. Paronychium is at the junction of the nail bed and skin at the sides
of the tip. The perionychium includes the nail bed, hyponychium, paronychium, and
eponychium.
prefer to anesthetize the dorsal skin at the metacarpo-
phalangeal level, then infi ltrate in the web spaces, as this
tends to be less painful for the patient. A 27- or 30-gauge
needle is used for infi ltration, and in general, 4 to 6 cc are
necessary to obtain satisfactory analgesia.
Tourniquet control can be achieved with a Turnicot;
however, these are not always available in ER settings,
and because they are rolled on the fi ngers to help exsan-
guinate the fi nger, they should not be used in the presence
of infection to avoid spreading the infection proximally.
Therefore, we prefer to use a 1-inch Penrose that is
placed circumferentially at the base of the affected fi n-
ger. It is tightened and clipped with a hemostat, making
sure that there is no rolling of the Penrose to minimize
possible damage to neurovascular bundles. The presence
of a large hemostat will help to remind the surgeon to
remove the tourniquet at the end of the case.
Generally, 5-0 nylon sutures are used for skin, while
7-0 chromic sutures are preferred for the nail bed,
although in the case of small children, a 5-0 chromic
suture may also be used for the skin. Fractures are
reduced with two small Kirschner (K-) wires, rather
than one, to help prevent axial rotation of the fracture
segment; and in smaller children, or smaller facture seg-
ments, when a 28-gauge K-wire is too large, a Keith nee-
dle has been used with success. Loupe magnifi cation is
highly recommended.
TECHNIQUES
Infections
Paronychia . Paronychia are infections of the nail fold
specifi cally, and are the most common infection of the
hand. The most common causative agent is Staphylococcus
aureus or Pseudomonas , although a variety of organisms
can be involved depending on the patient’s health and
exposure.

SOFT TISSUE RECONSTRUCTION OF THE UPPER EXTREMITIES • 593
FIGURE 50-2. Example of the treatment for a chronic paronychia. (A) Infection on
the undersurface of the dorsal roof of the nailfold. (B) Full thickness section of the dorsal
roof removed to eliminate infected tissue. (C) Post healing, visible nail slightly longer but
has normal appearance.
A
B
C
An incision and drainage is the mainstay of treatment.
After the area has been prepared and the area infi ltrated
with a digital block, pus can be expressed by enter-
ing the sulcus of the nail plate and the eponychial fold
and raising it with a fi ne elevator, such as the Kleinert-
Kutz. Sometimes the infection can spread to the sub-
ungual space. In this case, at least a portion of the nail
plate should be removed to ensure adequate drainage.
An incision through the eponychial fold is not necessary
and should be avoided, as necrosis of the fl ap tips can
ensue with nail fold scarring and a resultant nail defor-
mity. Prompt care is vital because these infections have
the potential to spread or become chronic paronychiae.
Chronic paronychiae, which have been present for
several months, or even years, are commonly caused by
mixed gram-negative organisms or fungi. Treatment con-
sists of marsupialization, which consists of excision of a
full-thickness, arc-shaped wedge of skin that is allowed
to heal secondarily ( Figure 50-2 ).
Felons . Felons are closed space infection of the fi nger
pulp. They tend to involve the thumb and index fi ngers
most frequently, and they typical present with pain. There
are numerous small vertical septa which serve to attach
the skin to the periosteum, providing stability to the fi n-
ger pulp. These septa are unyielding and in the presence
of infection, with an increase in pressure, pain ensues.
After a few days, if the felon is left untreated, the septae
will eventually erode, and the pain will often diminish,
falsely giving the impression that the condition is getting
better, when it is actually getting worse.
Once again, incision and drainage is the mainstay of
treatment, and several incisions have been suggested in
the treatment of felons. Small longitudinal incisions over
the maximal area of tenderness on the pad are preferred.
A “fi sh mouth” incision should be avoided, as this incision
will often result in skin necrosis and a painful deformed
fi ngertip. Likewise, transverse or high lateral incisions
may jeopardize the neurovascular bundle or devascular-
ize the fi ngertip ( Figure 50-3 ).
A differential diagnosis should always include her-
petic whitlow. These painful, whitish, vesicular lesions
are caused by the herpes simplex virus (HSV-1 in 60%
of case and HSV-2 in 40% of cases). Oftentimes, these
lesions occur in small children secondary to fi nger and
thumb sucking or health care workers who have direct
exposure to saliva (ICU nurses, etc). In the case of HSV-2
(genital herpes), herpetic whitlow is caused by autoin-
oculation. In all cases, the treatment is conservative, and
the patient is placed on an antiviral medication. These
lesions should not be drained, especially in small chil-
dren, as there are case reports of viral encephalitis ensu-
ing after drainage of these lesions ( Figure 50-4 ).
Trauma
Healing by Secondary Intention . Following a fi ngertip
amputation, if there is enough soft tissue coverage or if
only a small portion of bone needs to be removed to
achieve primary closure, secondary healing is the simplest
and easiest method of treatment for the practitioner. In
children, who have a high capacity for healing, this may

594 • CHAPTER 50
FIGURE 50-4. An example of an herpetic whitlow, which
can easily be mistaken for a paronychia or felon. However,
incision and drainage is contraindicated.
also be a suitable option. In larger wounds (.1 cm),
healing may take upward of 3 to 4 weeks, which may
result in an unnecessary and unacceptable delay of return
to work. In addition, as the wound bed contracts, this
will cause the nail to hook to varying degrees.
A scar will not always provide stable soft tissue cover-
age, and depending on the particular requirement of the
patient, secondary healing may be an unsuitable option.
In this case, a glabrous split or full-thickness skin graft
may be harvested from the hypothenar or proximal pha-
lanx area. Likewise, if nonglabrous skin is used, a variety
of donor sites are available from the ipsilateral arm or
the groin.
Nail Bed Laceration . When there is suspicion of a nail bed
laceration (eg, subungual hematoma/tuft fracture, avulsion
of the nail from the eponychium or paronychium), the nail
plate should be removed to inspect the nail bed. The most
sensitive physical fi nding for a nail bed laceration is a tuft
fracture, and a subungual hematoma that is greater than
50% of the nail bed will have a nail bed laceration about
two thirds of the time. Oftentimes, these crushing injuries
will result in complex stellate lacerations. In either case,
removal of the nail will reveal the injury, and the nail bed
should be repaired meticulously under loupe magnifi ca-
tion with 7-0 chromic sutures.
Salvage of All Usable Parts . In an amputation, when
the specimen is available, a determination must be made
by the surgeon whether it possible to replace this part.
Unless the amputation is proximal, microsurgical recon-
struction is usually not a reasonable option. At this point,
management is predicated on the level of the amputa-
tion in addition to the functional needs of the patient.
In an amputation distal to the lunula, the decision
whether to use a cap graft or a composite graft must be
made. In general, composite grafts do not survive in older
patients, especially if a smoking history is present, and are
not replaced. In children, the opposite is generally true.
However, some recent retrospective studies have shown a
rate of salvage in some individuals that might sway some
to attempt this. 1
A cap graft can be used for coverage of the amputated
fi ngertip. The amputated specimen is trimmed down
essentially to its dermal surface, removing all fat and bone.
This is easily done with a combination of sharp scissors
and a scalpel. Once this has been performed, “tailor tack-
ing” of the graft can be performed with a small incision
down the midline of the graft, which is lengthened and
the excess trimmed to achieve a well-contoured graft. A
bolster may be fashioned with nonabsorbable stitches;
however, if the graft is sewn on meticulously and a stable
dressing is applied that is not too tight, then a bolster is
not always necessary.
Of note, when the amputation occurs at or proximal
to the level of the lunula, and the amputated specimen
cannot be replaced, the residual germinal matrix needs to
be ablated to prevent the formation of a nail horn.
When multiple fi ngers have been injured, all usable
parts should be used to reconstruct the fi ngertips, even
FIGURE 50-3. Lateral and transverse incisions (A) are
not recommended for felon drainage, as risk of neurovascular
compromise is high. Likewise, a “fi sh mouth,” or even hemi
“fi sh mouth” (B) incisions carry the risk of a creating a painful
scar at the fi ngertip. (C) A small, longitudinal incision over the
infection is best tolerated.
A
C
B

SOFT TISSUE RECONSTRUCTION OF THE UPPER EXTREMITIES • 595
FIGURE 50-5. Epopnychial avulsion accounts for
approximately 15% of nail bed avulsions. Proper repair
mandates that exposure be obtained through incisions in the
eponychial fold at 90 degrees, so that the base may be inset
properly with mattress stitches.
if the tissues are not derived from the same fi nger. This
type of selective reattachment should be guided by the
particular needs of the patient; however, restoration of the
thumb index pinch is valuable for most daily activities.
Microsurgical Reconstruction . A wide variety of micro-
surgical procedures have been described for the fi nger-
tip, ranging from toe or partial toe transfer to arterialized
venous skin fl aps. Although they have been described by
many practitioners in the United States, they are not rou-
tinely performed, except perhaps in the case of thumb
reconstruction where not only restoration of coverage is
important but also sensibility. In Eastern cultures, these
fl aps tend to be performed more commonly, and they
can be a valuable reconstructive option for the carefully
selected patient. 2
Nail Bed Avulsion . Approximately 15% of all nail bed
injuries are avulsions. There are two major types of avul-
sion, and they each must be addressed in specifi c ways in
order to prevent a secondary nail deformity.
The fi rst of these is avulsion distal to the eponychial
fold. Originally, the recommendation was to separate the
nail bed from the nail plate and replace the nail bed;
however, we found that procedure too disruptive to the
avulsed nail bed, and have since then simply sewn the
avulsed nail plate and nail bed as one unit with favorable
results.
Avulsion of the nail and attached nail bed from
the eponychial fold must be exposed by refl ecting the
eponychial fold with incisions 90 degrees to the epony-
chial fold. Only in this way is possible to optimize visu-
alization and thereby meticulously repair the germinal
matrix so as to avoid a nail deformity ( Figure 50-5 ).
The nail should be removed to allow replacement of the
germinal matrix back into the nail fold.
Free Graft of the Nail Bed . If the avulsed nail bed is
not salvageable, it must be replaced with a free graft,
either a split-thickness sterile matrix or a full-thickness
graft of the germinal matrix. When ER facilities are ade-
quate, this may be done with a graft from the great toe.
If bone is visible, a graft should be attempted in any case,
as an avulsion injury can leave enough periosteum for
survival of the graft. However, if bare bone is exposed,
we have found that in the case of small grafts, they will
survive on the basis of plasmatic imbibition from the
edges of the nail bed, until the graft revascularizes.
Burns . Until recently, burns of the fi ngertips have gone
largely untreated. However, they create a characteris-
tic deformity of the nail. As the dorsal skin of the hand
contracts it will cause the eponychial fold to retract and
evert. Treatment of this deformity is very similar to treat-
ment of burn scar contractures elsewhere in the body.
The contracture is released sharply proximal to the
eponychial fold, allowing the correction of the eversion.
The defect is then grafted with a full thickness graft.
Favorable results of this procedure have recently been
described in a recent study. 3
V-Y Advancement
Atasoy-Kleinert Flap . This classic V-Y volar advance-
ment fl ap is highly reliable and very useful for dorsal
oblique fi ngertip amputations. The fl ap may only be
advanced about 1.0 to 1.5 cm, and it is necessary to
have enough relatively uninjured palmar tissue to create
and advance this fl ap. Once the V is designed based on
the palmer distal interphalangeal (DIP) crease, and the
incision has been made through the skin, a combination
of careful blunt and sharp dissection should be used
to disrupt the vertical septa in the fi nger pulp to allow
advancement of the fl ap. Care should be taken to avoid
excessive tension for two reasons: (1) necrosis of the
fl ap and (2) tension on the distal attachment of the

596 • CHAPTER 50
FIGURE 50-6. The MCP crease fl ap is designed between the MCP crease of the
thumb and the fi rst thumb crease distal, which is consistently 1.5 to 2.0 cm in width (A).
The radially based fl ap (B) is highly reliable, and offers the distinct advantage of primary
closure in a natural crease in the hand. The thenar fl ap (C) has several modifi cations, but
oftentimes cannot be closed primarily, resulting in a unaesthetic of painful scar.
fl ap this will tend to a hook nail, creating a bothersome
and unsightly secondary deformity that is diffi cult to
correct.
Kutler V-Y Flap . This fl ap is a bilateral lateral V-Y
advancement fl ap from the sides of the tip, similar to
the volar advancement fl ap. The main disadvantages of
this fl ap include possible disruption of the neurovascular
bundle resulting in hypersensitivity. The fl aps also do not
as readily advance as the volar V-Y fl ap; however, a good
indication for this fl ap is an oblique amputation of the
fi ngertip with more soft tissue on the sides.
Thenar Flap . Thenar fl aps provide durable coverage for
the index and the long fi ngers. In the classic description a
proximally based fl ap is created on the thenar eminence.
Although modifi cations have been described, thenar
fl aps often leave painful scarring or an anesthetic skin
graft in the palm because the donor site cannot be closed
primarily.
A modifi cation of this procedure proposed by Russell
et al. in 1981, presents a solution to some of the disad-
vantages of the standard thenar fl ap. The metacarpopha-
langeal (MCP) crease fl ap is a radially based fl ap that is
designed between the two creases at the thumb volar
MCP and can be closed primarily, leaving a fi ne-line scar.
This fl ap must be harvested with great care to identify
and protect the neurovascular bundles on the thumb, as
they are superfi cial and subject to injury ( Figure 50-6 ).
Cross-Finger Flap . When there is insuffi cient pulp for
the volar V-Y advancement fl ap, the cross-fi nger fl ap can
be used. This fl ap is harvested from the dorsum of the
fi nger adjacent to the injured fi nger. A fl ap is elevated
over the middle phalanx in a plane superfi cial to the per-
itenon of the extensor mechanism, to allow skin grafting
of the donor site. The fl ap is then turned 180 degrees like
a book page, and it is sewn into the adjacent fi ngertip
defect. The fl ap is then divided in 2 to 3 weeks. Although
this fl ap has the possibility of restoring sensation to the
injured fi ngertip, it has several drawbacks. The donor site
must be skin grafted, and being a two-stage procedure,
the immobilization of the fi ngers results in joint stiffness,
especially in a noncompliant patient who will not engage
in active range of motion exercises. Although stiffness
may be overcome in children, it is then often necessary to
pin the proximal interphalangeal (PIP) joint to prevent
fl ap separation. This fl ap should not be used in an older
patient population, or those with preexisting conditions
that predispose them to joint stiffness (eg, arthritis).
Reversed Homodigital Flap . As our understanding of
anatomy has increased, so has our ability to treat nail
bed injuries with more advanced procedures intended to
restore not only contour to the fi nger pulp, but sensation
as well.
When there is a fi ngertip amputation, tissue from the
same fi nger can be utilized by creating a distally based
fl ap along the midlateral line distal to the web space. The
A
B
C

SOFT TISSUE RECONSTRUCTION OF THE UPPER EXTREMITIES • 597
reversed digital artery fl ap can provide durable tissue with-
out invading the palm or another digit, and can be trans-
ferred as a single stage procedure.
ANATOMY
There are palmar vascular plexuses located at the MCP
joint, the PIP joint, and the fi nger pulp, as well as dorsal
vascular plexus at the nail fold, that provide an exten-
sive communication between the two digital arteries.
The blood supply to this island fl ap is from retrograde
fl ow through the digital artery after having crossed
through the vascular plexuses at the middle and distal
phalangeal level after the proximal ipsilateral artery is
transected and ligated. A dorsal branch of the proper
digital nerve can be incorporated into the fl ap design,
which then requires neurorrhaphy to the distal stump of
the severed digital nerve. Venous outfl ow is initially from
retrograde fl ow in the venous plexuses in the perivascu-
lar fat surrounding the digital arteries until local venous
anastomoses are established. A skin fl ap corresponding
to the fi ngertip defect is outlined along the radial or
ulnar side of the proximal phalanx. The ulnar side of
the index and radial side of the small are used to avoid
scars on the outside of the border digits. A midlateral
incision extends from the fl ap to the midpoint of the
middle phalanx ensuring the incision does not cross the
neutral axis of the PIP joint. The skin fl ap is incised and
elevated with the digital artery and a surrounding cuff
of subcutaneous tissue to ensure venous drainage. After
fl ap elevation the tourniquet is released. A microvascu-
lar clamp is applied to the digital artery proximal to the
fl ap. Bleeding from the tip of the fl ap and viability of the
digit is ascertained prior to dividing the artery. Donor
sites up to 2 3 3 cm can be closed primarily, otherwise
a full-thickness skin graft from the volar wrist or elbow
crease is applied.
A branch of the dorsal sensory nerve can be included in
this fl ap; however some studies have not included it with
similar results as they believe the fl ap become neurotized
eventually.
The main arguments against the use of this fl ap are the
necessity of skin grafting the donor site and the sacrifi ce of
the digital artery. And since this is a reversed fl ap, venous
drainage is dependent on a circuitous communicating and
collateral bypass route, which may pose a risk for venous
engorgement of the fl ap.
The Thumb
Special attention must be given to the thumb. Its impor-
tance in hand function can not be underestimated, and as a
result, several distinct methods of reconstruction have been
developed to treat the thumb specifi cally (Figure 50-7).
FIGURE 50-7. The three most commonly used local fl aps for thumb reconstruction
include the (A) Moberg advancement fl ap, (B) the Littler neurovascular island fl ap, and
(C) the “kite” or Foucher fl ap.
A
B
C

598 • CHAPTER 50
Moberg Advancement Flap . This classic fl ap, also
known as the rectangular volar advancement fl ap, has
been described as a method for reconstruction of thumb
defects of approximately 1.5 to 2.0 cm distal to the
interphalangeal joint. The major limitation of this fl ap
is its limited transposition which usually requires inter-
phalangeal joint fl exion to provide adequate soft tissue
coverage, although it can provide near-normal sensation
to the thumb tip. This fl ap, based on both neurovascular
bundles, is raised to the MCP crease, superfi cial to the
fl exor pollicis longus sheath. There are several fl ap varia-
tions that can be used to lengthen the distance of this fl ap
will advance, including raising the fl ap as an island fl ap,
and skin grafting proximally, extending the incisions past
the MCP crease, or excising Burrow triangles at the base.
Advancing the fl ap more than 2 cm carries the risk of an
interphalangeal joint contracture, which may or may not
be functionally limiting, depending on the degree of the
contracture and also the functional needs of the patient.
This fl ap cannot be used on the fi nger, as it will cause
joint contractures, and has the potential to disrupt the
blood of the dorsal skin distal to the PIP, which is depen-
dent on the volar neurovascular bundles.
Littler Method . Littler described this fl ap in the late
1950s as a neurosensory fl ap for thumb reconstruction as
an option for larger thumb defects when a Moberg fl ap
cannot be used. This fl ap is a neurosensory island fl ap
based on the nonopposition side of the ring fi nger (the
long fi nger can also be used as well) which is elevated
and transposed along with the skin and neurovascular
bundle and sutured into the volar aspect of the thumb.
The donor site defect is then skin grafted. Although in
the classic description only skin and subcutaneous tis-
sue are used, unpublished reports have described a com-
posite variation of this fl ap that includes bone. This can
be useful if multiple fi ngers have been injured, and the
opportunity exists to use an injured fi nger for recon-
struction of the thumb tip.
Although it can provide sensation to the tip of the
thumb, one of its major drawbacks is that cortical reori-
entation does not occur, especially in older patients, which
can be disturbing to some individuals. Also, this fl ap sac-
rifi ces one of the neurovascular bundles to a fi nger, so the
circulation to that fi nger must be assessed before the fl ap
is placed on the thumb.
First Dorsal Metacarpal Artery Flap . Initially de -
scribed by Foucher in the late 1970s, the term “kite
fl ap” has also been used to describe this fl ap. This fl ap,
much like the Littler neurovascular island fl ap, can pro-
vide sensation to the base of the thumb, but once again,
cortical reorientation may be a problem. This fl ap is a
neurovascular island fl ap that is raised from the dorsum
of the index fi nger proximal phalanx. It is based on the
ulnar branch of the fi rst dorsal metacarpal artery which
itself arises from the radial artery where it pierces the
two heads of the fi rst dorsal interosseous muscle in the
fi rst web space. When the fl ap is harvested, the plane
of dissection is superfi cial to the peritenon and index
fi nger and includes the fascial layer of the fi rst dorsal
interosseous muscle to ensure the arterial pedicle is
included. A superfi cial vein and branches of the radial
sensory nerve are harvested with the fl ap is well.
Secondary Nail Deformities/Complications
Although any condition may result in a nail deformity, the
most common cause of a nail deformity is the inappropri-
ate treatment of a nail bed trauma.
Pincer Nail (Trumpet Nail) . This deformity is character-
ized by an excessively curved and distorted nail in the
transverse dimension. Zook et al. presented a series of
49 patient in 2005, where the paronychial folds were
dissected laterally off the distal phalanx periosteum and
either alloderm or autograft dermis was used to elevate
the paronychial fold with good results ( Figure 50-8 ).
Split Nail . A split nail results from a scar in the sterile or
germinal matrix. The scar is generally oriented longitu-
dinally, although a transverse scar may cause a split nail,
but it is more likely to result in nonadherence of the
nail. In any case, treatment is centered on replacement
of the scar. For a narrow scar, minimizing the scar with
re-excision can help correct the deformity. The addition
of multiple z-plastys for a longitudinal scar is also very
helpful. However, for wide scars, a sterile matrix graft
should be used. Relaxing incisions to help advance the
nail bed have been described, but in our experience, this
has not produced a satisfactory outcomes.
A sterile matrix graft can be obtained from the adja-
cent portion of sterile matrix or the toes, and tends to
satisfactorily correct the deformity. For a distal split nail,
successful treatment has also been described for place-
ment of a thin piece (0.20-inch) of silicone sheeting
between the nail and the nail bed.
Tumors
Glomus Tumor . Subungual glomus tumors are benign
lesions of the glomus apparatus, which is responsible for
thermoregulatory control. The glomus apparatus contains
an afferent vessel, a Sucquet-Hoyer canal, and multiple
shunts in the glabrous skin of the hand and beneath the
nail beds.
A patient with a glomus tumor often presents with the
classic triad of cold hypersensitivity, paroxysmal pain, and
exquisite pinpoint pain. The pain is not usually relieved
with salicylates, and can help differentiate a glomus tumor
from other conditions.

SOFT TISSUE RECONSTRUCTION OF THE UPPER EXTREMITIES • 599
Physical fi ndings of a glomus tumor include painful sub-
cutaneous nodules in the subungual region. Sometimes, a
nail deformity is present, and/or it is discolored with a blu-
ish tinge. Approximately 75% of glomus tumors are found
in the hand with about two thirds of these in the fi ngertip.
Multiple tumors may exist and should be looked for. Pain
can be elicited by the examiner with light touch or cold
exposure. Imaging of glomus tumors includes MRI, which
delineates a dark, well-defi ned lesion on T1-weighted
images and a bright lesion on a T2-weighted image.
Treatment of the glomus tumor involves surgical exci-
sion. Once the nail plate is removed and the eponychial
fold is refl ected, if necessary, a small, longitudinal inci-
sion is utilized to extract the glomus, which will most
often “shell out” easily. A bilenticular incision is not
necessary, as the redundant nail bed will conform over
time without excess once the glomus has been removed.
The recurrence rate can be as high as 20%, and thus, the
matrix should be carefully examined and any suspected
remnant of the tumor removed ( Figure 50-9 ).
DIP Ganglion . The DIP ganglion or mucous cyst is not
as common as the typical volar or dorsal wrist ganglions,
but it does occur with some frequency. It is frequently
treated in the same manner as other ganglions of the
hand with cyst excision and as a result often reoccurs.
These ganglions usually present as cystic lesion off the
midline on the dorsum of the distal phalanx over or just
distal to the DIP joint. The patient may give a history of
intermittent spontaneous drainage, sometimes through
the eponychial fold. The ganglion will often but not
invariably communicate with the DIP joint, and although
there are studies which have shown lack of refl ux back
into the joint, it is still not a wise idea to aspirate these
for refi lling is almost certain.
The most effective method of treatment actually does
not involve treatment of the ganglion itself per se, but its
root cause which is an osteophyte of the DIP joint most
commonly due to osteoarthritis.
A T-shaped incision, which can be extended into an
H-shaped incision if necessary, is utilized. Care must be
taken to not violate the extensor mechanism, as it can
be lacerated upon entering the wound. Once the lateral
edge is elevated the dorsal joint osteophytes are rongeured
away and the ganglion itself is simply drained, not excised.
Recurrence rates are extremely low in my experience with
this technique ( Figure 50-10 ).
Subungual Pigmented Lesions . Subungual lesions of
the nail bed are not uncommon, and as a result, they
must be investigated carefully to rule out the possibility
of melanoma. Melanomas of the hands and feet tend to
have a poorer prognosis as they are often mistaken for
other benign conditions, such as viral warts, and appro-
priate treatment is often delayed. Therefore, it is wise
when evaluating these lesions to obtain a careful history
that includes when the patient fi rst noticed this lesion,
how the lesion has changed over time, sun exposure
and family predisposition to melanoma, and to carefully
examine, and re-examine , these lesions when necessary.
FIGURE 50-8. The pincer nail, or trumpet nail deformity (A) causes a characteristic
deformity. A dermal autograft (B) can be obtained from a variety of locations. Homograft
dermis has also been used with success. After tunnels are made which elevate the lateral
nail bed (C), the dermis can be pulled through most easily with a suture (D).
A
B
C
D

600 • CHAPTER 50
FIGURE 50-10. The DIP ganglion is accessed through
an H-shaped incision (A), and although the ganglion can
cause a nail deformity, it is important to understand that the
osteophytes in the DIP joint (B) are ultimately responsible for
these changes. Therefore, they must be debrided (C) taking
care not to injury the extensor mechanism.
FIGURE 50-9. The glomus tumor can often be diffi cult
to visualize clinically (A), but once its presence has been
confi rmed, the eponychial fold is refl ected back (B), and a
longitudinal incision is used to extract the glomus (C). The nail
bed is then sutured back together without trimming excess
(D), as the nail bed will contract and recontour over time.
FIGURE 50-11. Patient with an example of a nail streak
which should be treated with biopsy.
In many cases, the patient may not recall a history of
direct trauma to the nail, and in these cases, it is useful
to use the technique of scratching the nail plate proximal
and distal to the pigment spot and observing if the lesion
advances with nail growth. If the scratches move with
the nail it is a subungual hematoma secondary to trauma.
If the scratches move away from the pigment and there
is a suspicion of melanoma, the lesion should be biop-
sied. Removal of the nail plate is not always necessary;
and in some instances, once the nail plate is removed, the
exact location of the lesion may be diffi cult to determine.
For this reason, some method of marking the lesion prior
to nail plate removal is helpful. If a melanoma is subse-
quently diagnosed, then it should be staged and treated
accordingly with the appropriate resection, which in
many cases is an amputation at the adjacent joint.
For less aggressive tumors, such as some well-
differentiated squamous cell carcinomas, judgment
should be exercised as to the extent of the resection in
order to maximize function. For instance, a professional
musician’s fi nger might be treated differently than that
of a retired octogenarian. In any case, clear margins are
a must, and if the lesion extends to involve the bone,
an amputation at the adjacent joint is most likely nec-
essary. More importantly, clinical suspicion for a tumor
must be present, as studies have revealed that the aver-
age time from fi rst observation to diagnosis to treatment
is approximately 4 years ( Figure 50-11 ).
A
B
C
D
A
B
C

SOFT TISSUE RECONSTRUCTION OF THE UPPER EXTREMITIES • 601
REFERENCES
1. Lille S, Brown RE, Zook EG, Russell, RC. Free nonvascular-
ized composite nail grafts: an institutional experience. Plast
Reconstr Surg . 2000;105:2412–2415.
2. Endo T, Kojima T, Hirase Y. Vascular anatomy of the fi nger
dorsum and a new idea for coverage of the fi nger pulp defect
that restores sensation. J Hand Surg . 1992;17A:997–932.
3. Donelan MB, Garcia JA. Nailfold reconstruction for the
correction of burn fi ngernail deformity. Plast Reconstr Surg .
2006;117:2303–2308.
SUGGESTED READING
Brown RE, Zook EG, Russell RC. Fingertip reconstruction with
fl aps and nailbed grafts. J Hand Surg . 1999;24A:345–351.
Brown RE. Acute nail bed injuries. Hand Clin. 2002;18(4):
561–575.
Foucher G, Braun JB. A new island fl ap from the dorsum of the
index to the thumb. Plast Reconstr Surg . 1979;63:344–349.
Gingrass MK, Brown RE, Zook EG. Treatment of fi ngernail
deformities secondary to ganglions of the distal interphalan-
geal joint. J Hand Surg . 1995:20;502–505.
Jebson PJ. Infections of the fi ngertip. Paronychias and felons.
Hand Clin . 1998;14:547–555.
Russell RC, Casas LA, Management of fi ngertip injuries. Clin
Plast Surg . 1989;16(3):405–425.
Russell RC, Van Beek EG, Wavak P, Zook EG. Alternative hand
fl aps for amputations and digital defects. J Hand Surg . 1981;
6:399–405.
Sommer N, Neumeister MW. Tumors of the perionychium. Hand
Clin . 2002;18(4):673–689.
Zook EG, Chalekson CP, Brown RE, Neumeister MW. Correc-
tion of pincer nail deformities with autograft or homograft
dermis: modifi ed surgical technique. J Hand Surg . 2005;
30(2):400–403.
Zook EG, Russell RC. Reconstruction of a functional and aes-
thetic nail. Hand Clin . 1990;6(1):59–68.

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51
c h a p t e r
Fractures of the Hand and Wrist
Jeffrey M. Jacobson, MD / Walter B. McClelland, Jr., MD / James P. Higgins, MD
and may or may not require an initial reduction or formal
immobilization. Unstable injuries are more apt to require
operative stabilization and should be followed closely
if attempts are made to treat them nonoperatively. A
fracture initially felt to be stable may reveal itself to be
unstable by loss of reduction on serial x-rays. In certain
circumstances, even stable injuries warrant operative
intervention. Some examples would include open frac-
tures, fractures with signifi cant soft tissue injury, and
fractures necessitating early rehabilitation to improve
functional outcomes.
The primary goal of treatment is the timely restoration
of function through acceptable bony alignment, length,
and rotation while maintaining adjacent joint range of
motion. Although individual patient circumstances and
fracture characteristics must be considered on a case-by-
case basis, there are certain general principles that tend
to guide treatment planning. Optimal outcomes will be
achieved if the treatment method is tailored to the unique
clinical situation, and the surgeon is facile with the techni-
cal aspects of the surgery and the integrated rehabilitation
plan. Once a treatment plan is formulated, it should then
be discussed with the patient to establish realistic goals
and expectations for acute care, rehabilitation, and long-
term functional outcome.
Concepts regarding fracture management of the hand
and wrist are varied, and guidelines for treatment of these
fractures are specifi c to the mechanism of injury, natural
history of the untreated fracture, relative stability of reduc-
tion, proximity or involvement of joints, and morbidity of
operative techniques. 1 , 2 Given the breadth of injury types
and fi xation options, an exhaustive review is beyond the
scope of this text. Instead, this installment will address
management and operative techniques of the more com-
mon fractures by anatomic location.
PATIENT EVALUATION AND SELECTION
The hand and wrist are integral components of nearly all
human pursuits, including work, leisure, and activities of
daily living. This level of involvement makes injuries to
these structures common and long-term disability devas-
tating. Hand and wrist injuries pose special intellectual and
technical challenges for upper extremity surgeons, requir-
ing a knowledge of complex regional anatomy, strict adher-
ence to good surgical technique, and a full understanding
of rehabilitation methods and goals.
The patient evaluation begins with an accurate diag-
nosis through a complete history and physical examina-
tion, and adequate imaging studies. For most injuries of
the hand and wrist, an x-ray evaluation is suffi cient for
diagnosis and treatment decisions. For injuries distal to
the carpus, appropriate x-ray views generally include
posteroanterior, lateral, and oblique views of the hand,
as well as lateral views of an injured digit. For injuries
to the carpus, posteroanterior, lateral, and oblique views
should be obtained. Special x-ray views are available for a
variety of suspected injuries and should be utilized when
appropriate. If questions exist as to whether a certain
fi nding is pathologic or native to the patient, images of
the contralateral extremity can be obtained for compari-
son. In certain circumstances, elaborated below, advanced
imaging modalities may be necessary to confi rm or fur-
ther evaluate a suspected injury. Because many injuries
to the hand and wrist involve load transmission through-
out the upper extremity, care must be taken to evaluate
and rule out concomitant injury to the forearm, elbow,
or shoulder.
The fi rst determination in the management algorithm
is classifying an injury as stable or unstable. Stable inju-
ries are ones in which length, alignment, and rotation are
expected to be maintained throughout fracture healing

604 • CHAPTER 51
PATIENT PREPARATION
Fracture fi xation of the hand and wrist can typically be
accomplished with a limited amount of additional sup-
plies. The patient should be placed supine on the opera-
tive table with the affected extremity extended on an arm
board. Care should be taken to avoid excessive shoulder
abduction to prevent traction injury to the brachial plexus.
A nonsterile tourniquet should be applied to the upper
portion of the patient’s arm, even if tourniquet control is
not anticipated during the case. A lead hand or other hand
positioning device can assist in maintaining the hand and
wrist in the desired position during the case, freeing the fi rst
assistant to take part in other portions of the procedure.
A C-arm should be available to evaluate the adequacy
of reduction and appropriate placement of hardware.
Ideally, this should enter the surgical fi eld from the end of
the arm table to avoid the surgeon or assistant having to
move while obtaining fl uoroscopy. Loupe magnifi cation
can be helpful during dissection to identify and protect
important soft tissue structures. If concomitant neurovas-
cular repair or reconstruction is necessary, a microscope
may provide better visualization than loupes alone.
Regarding anesthesia, many cases may be managed
with either local or regional anesthetic. This can be com-
bined with sedation as necessary. In the setting of lengthy
or complicated procedures, or if the patient is diffi cult to
sedate by lesser means, general anesthesia may be required.
These decisions should take into account the length and
type of the procedure, health status of the patient, and
skill level and preferences of the anesthesiologist.
The most common implant utilized during fracture fi x-
ation of the hand and wrist is the Kirschner wire (K-wire).
It comes in a variety of sizes, with .0350, .0450, and .0540
being the most commonly used in hand and wrist surgery.
Wires smaller than .0350 provide inadequate stability for
bony fi xation, and those larger than .0540 can be over-
whelming for work on small tubular bones.
A modular hand tray is also of great value, providing
specialized bone reduction forceps, as well as plate and
screw systems ranging from 1.0 to 2.4 mm in size. While
plates have typically been preferred for fractures proximal
to the metacarpophalangeal (MCP) joint, newer low pro-
fi le designs have expanded the use of these implants to the
proximal and middle phalanx. Plates are typically of great-
est benefi t in transverse fractures, fractures with signifi cant
comminution, or long fractures that involve the majority
of a given segment. In oblique fractures, screws can provide
stable fi xation with less soft tissue dissection and implant
bulk. When screws alone are used, a balance must be
achieved between orienting perpendicular to the fracture
to maximize compression and orienting perpendicular to
the long axis of the bone to neutralize shear forces. 3 In gen-
eral, given the increased dissection required for implan-
tation, plates should be applied only when less invasive
implants provide inadequate reduction or stability.
The fi nal implant category is variable pitch headless
compression screws. These implants provide compression
across a fracture or potential space without use of a lag
technique. These implants have revolutionized the fi xation
of scaphoid fractures in particular and are widely used in
other forms of intercarpal stabilization. Suture anchors are
another useful implant in the repair and reconstruction of
the hand and wrist. However, given that their use is pri-
marily for soft tissue injuries, their use will not be further
described here.
In general, a surgeon must strive to employ minimally
invasive techniques while achieving maximal stability of
the construct. Additional dissection may cause further
insult to the tenuous soft tissue structures of the hand
and digit, whereas more rigid stabilization allows earlier
rehabilitation and motion without concern for loss of
fi xation.
TECHNIQUES FOR FRACTURES
OF THE HAND
Fractures of the Distal Phalanx
Distal phalanx fractures are generally encountered as
extra-articular tuft and shaft fractures related to crush
injuries. Intra-articular fractures are also common and
result from avulsion fractures of the terminal extensor ten-
don (“mallet fi nger”) or fl exor digitorum profundus tendon
(“jersey fi nger”). Tuft fractures are often associated with an
injury to the specialized nail elements, which must be fully
evaluated and appropriately managed to avoid a chroni-
cally deformed or painful nail. The bony injury is often
adequately managed with irrigation and a short period
(1–3 weeks) of splint immobilization, which should not
include the proximal interphalangeal (PIP) joint. Not
infrequently, these fractures will fail to unite, resulting in
a fi brous union. It bears mentioning that if the nail plate is
removed to decompress a subungual hematoma or repair
a nail bed laceration, the tuft fracture should now be con-
sidered open, and treatment should include a short course
of oral antibiotics.
If the fracture is diaphyseal with more sizeable fracture
fragments, consideration can be given to K-wire stabiliza-
tion, particularly if the fragments are displaced. A single
0.28- or 0.35-inch longitudinal pin is usually suffi cient and
may be advanced across the distal interphalangeal joint for
added stability, if necessary.
Extra-Articular Fractures of the
Proximal and Middle Phalanx
Diaphyseal and meta-diaphyseal fractures of the proxi-
mal and middle phalanx come in a variety of forms, and
management decisions are often based on subtle nuances.
Many of these fractures are reducible and stable and can
be treated in a nonoperative fashion with 3 to 4 weeks of
buddy taping and/or splinting. Proximal phalangeal shaft
fractures are often angulated apex volar due to the pull of
the intrinsic muscles and the action of the extensor mech-
anism, whereas their middle phalanx equivalents can be
angulated in any direction dictated by the injury mecha-
nism and fracture location.

FRACTURES OF THE HAND AND WRIST • 605
Certain fracture patterns more commonly require
greater intervention. Spiral oblique fractures may
require open treatment due to their tendency to fore-
shorten and rotate. Transverse midshaft fractures require
particularly close monitoring as they tend to angulate
over time.
Surgical treatment of many of these fractures is often
adequately performed with K-wires. In the case of spiral
oblique fractures, interfragmentary screw fi xation can pro-
vide fracture compression while eliminating the concern of
pin tract infection ( Figure 51-1 ), provided the fracture line
is at least 1.5 times the diameter of the bone. Regardless of
technique, fracture management of the phalanges carries a
great risk of motion loss. Operative techniques are aimed
at avoiding the tendon adhesions that accompany exces-
sive soft tissue dissection. Particular caution is exercised
in surgical approaches or hardware placement in or about
the PIP joint, as it is the greatest contributor to the digit’s
composite range of motion. 4
Condylar Fractures of the
Proximal and Middle Phalanx
Condylar fractures of the phalangeal head are typically
unstable and require surgical intervention. Despite the
small size of the bony fragment, fi xation with a single
K-wire is typically inadequate for unicondylar fractures.
Therefore, multiple K-wires or 1.0 to 1.5 mm lag screws
should be utilized. 5 For bicondylar or comminuted frac-
tures, treatment options range from open reduction and
internal fi xation (ORIF), to traction/external fi xation, to
primary arthrodesis. Regardless of the form of fi xation,
patients should be counseled about the high likelihood of
motion loss postoperatively. An oblique x-ray can be very
useful in evaluation of the fracture.
Pilon Fractures of the
Proximal and Middle Phalanx
Pilon fractures refer to phalangeal base fractures associated
with an axial-loading mechanism ( Figure 51-2 ). They are
associated with varying degrees of articular depression and
splaying of the articular fragments. They pose a diffi cult
treatment dilemma for upper extremity surgeons, with a
high rate of residual articular incongruity and motion loss
postoperatively. While conservative management has been
described, these injuries are typically best treated with
traction/dynamic external fi xation or ORIF with or with-
out bone grafting. 6
Fracture-Dislocations of the PIP Joint
The PIP joint is the dominant contributor to digit motion.
Thus, ongoing derangement in this area is a signifi cant risk
factor for poor clinical outcomes and low patient satisfac-
tion. Although lateral and volar dislocations occur, they
are far less frequently encountered than dorsal disloca-
tions. When these injuries occur as fracture-dislocations,
the evaluation must include an assessment of the size of
the volar fragment and the stability of the joint following
reduction. When the fracture fragment represents 40% of
the articular surface or less, the collateral ligaments’ inser-
tion on the middle phalanx is maintained and the joint
tends to remain stable following reduction. Beyond 40%,
the collateral ligament insertion is typically contained in
the volar fracture fragment, resulting in persistent instabil-
ity following reduction.
In the case of a stable injury, the joint is initially
immobilized with a dorsal blocking splint in a position of
stable fl exion (typically 15–30 degrees) for 1 to 2 weeks.
FIGURE 51-1. (A) A spiral oblique fracture of the
proximal phalanx. The fracture shortening and apex volar
angulation would result in an unsatisfactory clinical result if
treated conservatively. (B) Stabilization using two 1.5-mm
compression screws restores the alignment anatomically.
A
B
FIGURE 51-2. A pilon fracture of the index fi nger middle
phalanx. Note the articular widening and central depression
resulting from the axial load mechanism. This patient required
open reduction internal fi xation to reduce the articular
incongruity.

606 • CHAPTER 51
Full-fi nger fl exion allowed by PIP extension is initially
blocked. The digit is gradually extended within the range
of stability over the next 2 to 4 weeks. Early commence-
ment of supervised hand therapy is critical in these injuries
to prevent excessive stiffness. If initial immobilization of
the PIP joint beyond 30 degrees is required for joint sta-
bility, then the risk of fl exion contracture is too great and
surgical intervention should be considered.
In unstable or irreducible PIP joint fracture-dislocations,
open reduction with or without fi xation is indicated. The
risk of open management through wide exposure of these
fractures is a signifi cant loss of motion, so minimally inva-
sive techniques should be employed when feasible. Fracture
fragments can often be manipulated with joystick K-wires
to set the stage for percutaneous pinning with dynamic or
static external fi xation. Postoperatively, there is a premium
on early active motion to take advantage of the anatomic
reduction and fracture stability.
Perhaps the most challenging fracture of the hand is the
unstable PIP fracture dislocation with severe comminu-
tion and impaction of the volar lip of the middle phalanx.
Adequate reduction of these fractures is diffi cult to obtain
and often impossible to maintain without reestablishing
the stability afforded by the volar base of the middle pha-
lanx. In the absence of a large enough fragment to achieve
adequate fi xation, three modes of surgical management
have been proposed.
1. Dynamic external fi xation with volarly directed force
on the middle phalanx: This combination of effects
is achieved by a “force coupling” fi xation technique,
which prohibits dorsal translation of the joint while
permitting active fl exion. The ultimate joint stability
relies on a combination of bone callous, fi brocarti-
lage, and scar tissue that forms during this period of
provisional stabilization ( Figure 51-3 ).
2. Volar plate arthroplasty: An open volar approach
to the joint is used to remove impacted fragments.
The volar lip of the middle phalanx is recreated
with advancement of the volar plate on its proximal
attachments.
3. Osteochondral autografting: This technique takes
advantage of the anatomic similarities in the bicon-
cave articular surface of the base of the proximal
phalanx and the distal surface of the hamate. By har-
vesting and transplanting the dorsal majority of the
hamate’s articulation with the ring fi nger and small
fi nger metacarpal, articular congruency is restored,
allowing early motion with minimal donor site mor-
bidity ( Figure 51-4 ). 7
Fracture-Dislocations of the MCP Joint
MCP joint dislocations are much less common in the adult
than their PIP counterpart due to the relatively sturdy lig-
amentous housing of the MCP articulation. When these
dislocations do occur, the vast majority are dorsal disloca-
tions affecting the vulnerable border digits. Patients pres-
ent with pain, an inability to fl ex the MCP joint, and a
posture of mild hyperextension at the MCP joint with
slight fl exion of the distal joints. In the case of a sublux-
ated joint, closed reduction is generally possible with dor-
sally applied pressure to the base of the proximal phalanx.
Axial distraction should be avoided as it may encourage
the volar plate to interpose itself in the joint and make
closed reduction impossible. In the case of a true disloca-
tion, the volar plate is often already interposed, requiring
an open reduction.
Fractures of the articular surface of the proximal pha-
lanx are generally treated with internal fi xation. Metacarpal
head fractures, while rare, can generally be treated in a
nonoperative manner unless a large portion of the articular
FIGURE 51-3. Dynamic ex-fi x device used for indirect
reduction of a middle phalanx base fracture. Stable reduction
by ligamentotaxis allows early motion as the fracture unites.
FIGURE 51-4. Pre- and postoperative imaging of a
hemi-hamate reconstruction for a middle phalanx condylar
base fracture. Volar plate arthroplasty was contraindicated
due to the size of the articular surface involved, while the
degree of comminution precluded direct reduction and
stabilization.

FRACTURES OF THE HAND AND WRIST • 607
surface is involved or there is greater than 1 mm of articu-
lar incongruity. Even in this setting, severe comminution
may preclude operative intervention if hardware purchase
is expected to be limited.
Metacarpal Fractures of the Digits
Metacarpal fractures can be considered in three subsets:
(1) fractures of the metacarpal neck, (2) fractures of the
metacarpal diaphysis, and (3) metacarpal base fractures
and carpometacarpal (CMC) dislocations.
Fractures of the metacarpal neck occur commonly
and most frequently affect the fourth and fi fth metacar-
pals. The increased mobility of the ulnar carpometacarpal
joints leaves these metacarpals vulnerable to off-axis load-
ing when the metacarpal head strikes an unyielding object.
While it is agreed that the reduction of these apex-dorsally
angulated fractures must correct any rotational deformity,
there exists signifi cant controversy about the acceptable
postreduction angulation.
Reduction of a “boxer’s fracture” is reliably effected by
use of the Jahss maneuver, in which the MCP is fl exed
90 degrees and a dorsally directed force is applied to the
metacarpal head through manual pressure on the proximal
phalanx ( Figure 51-5 ). If a stable reduction can be achieved,
immobilization in an ulnar gutter splint for 4 to 5 weeks
followed by protected return to motion is appropriate.
Even with a signifi cant degree of angulation, patients can
function well in the absence of rotational deformity. They
may notice a fl attening of the dorsal knuckle or a promi-
nence of their metacarpal head in their palm during grip,
but range of motion is typically quite satisfactory given the
compensatory motion of the CMC joint.
If the patient demonstrates malrotation or an inability
to extend the MCP joint to neutral position, or if a stable
reduction cannot be maintained, surgical intervention is
recommended. In these cases, soft tissue dissection should
be minimized to avoid the formation of mobility-limit-
ing scar tissue. While various methods of treatment have
been described, the authors’ preference is to treat the vast
majority of these in a closed fashion. We avoid plating and
collateral recess pin techniques when possible to minimize
joint stiffness and employ transmetacarpal pinning and
limited incision intramedullary “bouquet” pinning tech-
niques more commonly ( Figure 51-6 ). 8
FIGURE 51-5. Clinical photograph of the Jahss
maneuver for reduction of metacarpal neck fractures. Applying
force to the head of the proximal phalanx allows a greater
lever arm and more force generation to assist in reduction.
FIGURE 51-6. (A) Clinical photo demonstrating signifi cant malrotation through a
small fi nger metacarpal neck fracture. (B) Pre- and postoperative demonstrating fracture
reduction and stabilization using the bouquet pinning technique. Increasing the number
of intramedullary pins greatly increases the construct rigidity.
A
B

608 • CHAPTER 51
Fractures of the metacarpal diaphysis are treated based
on the fracture characteristics, with the greatest empha-
sis placed on malrotation. Most isolated shaft fractures
without malrotation can be treated in a closed fashion.
Spiral fractures, open fractures, and multiple metacarpal
fractures are usually treated with operative fi xation due
to increased diffi culty with rotational control. Particular
caution is exercised for the border digits, which may
demonstrate more rotational instability than their central
counterparts. Closed fractures of the central digits may
remain stable, even in the setting of spiral fracture pat-
tern or comminution, due to the stability afforded by the
intermetacarpal ligament and interossei attachments to
the surrounding uninjured metacarpals. If a stable reduc-
tion cannot be obtained, operative treatment must be
pursued with fi xation appropriate to the fracture pattern.
Transverse diaphyseal fractures are usually treated with
plate fi xation, whereas more oblique and spiral fractures
are treated with interfragmentary screw fi xation if pos-
sible ( Figure 51-7 ).
Metacarpal base fractures are most frequently seen in
the fourth and fi fth digits and are often associated with
fractures of the neighboring carpal bones. These fractures
can best be visualized on an oblique supination radiograph
and can be missed on standard anteroposterior and lateral
views. They are generally treated by ORIF to reestablish
the preinjury anatomy of the CMC joints and prevent
recurrent dorsal and ulnar subluxation of the metacarpal
bases. If a dorsal dislocation is encountered, CMC pinning
is indicated given the typical instability associated with
this injury.
Metacarpal Fractures of the Thumb
The thumb metacarpal is most susceptible to injury at
its base, fracturing much less commonly in its diaphysis.
Extra-articular fractures are treated in a similar fashion
to metacarpal diaphyseal fractures. Because the thumb
derives most of its utility and function from its wide range
of motion at the CMC joint, intra-articular fractures at
the metacarpal base are potentially morbid injuries if not
appropriately treated.
Bennett fractures are intra-articular fractures of the
base of the thumb metacarpal produced by an axial load
sustained by a fl exed joint. The fracture line splits the
articular surface, leaving an undisplaced smaller articular
fragment on the volar ulnar surface attached to the ante-
rior oblique ligament of the CMC joint. The larger portion
of the articular surface, which includes the remainder of
the thumb ray, is displaced dorsally, proximally, and radi-
ally with the intact metacarpal shaft due to the unopposed
pull of the abductor pollicis longus.
While some authors advocate closed treatment of
these fractures if the articular step-off is less than 1 mm,
these fractures are unstable due to the effects of the sur-
rounding musculature on the distal metacarpal and are
best treated with closed reduction and percutaneous
pinning or ORIF. Percutaneous pinning is often selected
if an anatomic closed reduction can be achieved and the
volar-ulnar fragment is too small to provide purchase for
screw fi xation. If an adequate closed reduction cannot be
achieved, and/or if the fracture fragment is large enough
to accommodate rigid internal fi xation, open treatment is
considered. 9
FIGURE 51-7. (A) Preoperative imaging demonstrating
spiral fractures of the index and middle fi nger metacarpal with
shortening and rotational malalignment. (B) Fixation using two
techniques. The index fi nger reduced easily and demonstrated
stability with three interfragmentary compression screws. The
middle fi nger had an additional nondisplaced fracture line
extending distally, necessitating bridge plate fi xation.
A
B

FRACTURES OF THE HAND AND WRIST • 609
Rolando fractures can vary from a three-part intra-artic-
ular T or Y fracture to a severely comminuted variant that
defi es fragment characterization. Since restoration of the
articular anatomy is the most important goal in treatment
of these fractures, they are almost always best treated in
an open fashion. If plating or screw fi xation is achieved,
patients are started on supervised motion shortly after
surgery. If pin fi xation alone is utilized, 5 to 6 weeks of
thumb spica splinting is required. If fracture severity or
comminution mandates the use of external fi xation, a lon-
ger period of immobilization may be necessary to allow
fracture consolidation.
TECHNIQUES FOR FRACTURES
OF THE CARPUS
Fracture management for each of the carpal bones will be
described with more detailed discussion dedicated to those
of greater clinical relevance (See Table 51-1).
Scaphoid Fractures
Scaphoid fractures are one of the most common fractures
of the upper extremity and comprise more than 75% of
all carpal bone fractures. The classic mechanism of injury
is axial loading with wrist hyperextension, commonly sus-
tained during a fall on an outstretched hand. Wrist exten-
sion greater than 90 degrees and radial deviation at the
time of compressive loading places the scaphoid at greatest
risk of fracture. 10 Approximately 70% of scaphoid fractures
occur through the midportion, commonly referred to as
the waist. The remainder are divided between the distal
pole (10%–20%), the proximal pole (5%–10%), and the
tubercle (5%) (Table 51-1).
The blood supply to the scaphoid is derived from the
radial artery through both volar and dorsal branches.
These branches pierce the cortex at the distal pole and
dorsal ridge, respectively, and feed the bone in a retro-
grade fashion. This anatomic fi nding makes fractures of
the proximal pole at increased risk for nonunion. Plain
fi lm radiographs should be obtained, including postero-
anterior, lateral, and oblique views. A “scaphoid view,” a
posteroanterior radiograph with the wrist in extension
and ulnar deviation, can be invaluable by providing a pro-
fi le view of the scaphoid waist. A clenched fi st view can
be added if concern for a scapholunate ligament injury
exists. Nondisplaced fractures are not always immedi-
ately visible on plain fi lms. If the clinical suspicion is high
for a scaphoid fracture, one of the following two treat-
ment plans is employed. The fi rst option involves empiri-
cally immobilizing the patient in a thumb spica splint
or cast and repeating the x-rays 2 to 3 weeks postinjury.
Marginal resorption will typically occur at the fracture
site over this time, rendering the fracture line more vis-
ible. The second option involves the use of advanced
imaging modalities, including CT scan, MRI, and bone
scan. While all can be used to accurately diagnose acute
fractures of the scaphoid, MRI is our preferred method,
since it allows visualization of the surrounding soft tissue
structures, an assessment of the vascularity of the proxi-
mal pole, and detection of the subtle edema pattern of
an occult fracture. 11
Acute nondisplaced scaphoid fractures can be success-
fully treated both operatively and nonoperatively. The
method by which conservative care is undertaken is a mat-
ter of much debate, with no consensus in the literature
regarding length of immobilization, appropriate position
of the immobilized wrist, or casting technique. Our pro-
tocol involves a short-arm thumb spica cast with the wrist
in neutral position until the patient’s clinical examination
and radiographs demonstrate evidence of bony union (typ-
ically 12–16 weeks for a waist fracture). A CT scan can
be obtained if union is in question to look for evidence
of bone bridging the fracture site. In cases of undisplaced
waist fracture, the decision to proceed with cast immobi-
lization for a prolonged period of time should take into
consideration the patient’s physical demands, social situa-
tion, and handedness.
If a patient is unable or unwilling to tolerate 12 to
16 weeks of immobilization, or if the fracture involves the
proximal pole, percutaneous or mini-open screw fi xation is
appropriate. With the development of cannulated variable
pitch screws, stabilization of these fractures can be achieved
in a reliable and minimally invasive fashion ( Figure 51-8 ).
This form of treatment allows a shorter period of immobi-
lization and a more rapid return to activities. In addition,
there is some data to suggest that screw fi xation decreases
the time to union, although this has not been consistently
borne out in the literature.
In general, any acute scaphoid fracture that is com-
minuted or displaced more than 1 mm, or is associated
with concomitant ligamentous injury of the wrist, is
best managed with an open reduction and stabilization.
TABLE 51-1. Relative Incidence of
Fractures of the Carpal Bones
Bone
Number
Percentage
of Total
Scaphoid
5036
78.8
Triquetrum
880
13.8
Trapezium
144
2.3
Hamate
95
1.5
Lunate
92
1.4
Pisiform
67
1.0
Capitate
61
1.0
Trapezoid
15
0.2
6390
From Amadio PC, Moran SL. Fractures of the carpal bones. In:
Green DP, Hotchkiss RN, Pederson WC, Wolfe SW, eds. Green's
Operative Hand Surgery . 5th ed. Philadelphia: Churchill-Livingstone;
2005:711. Copyright Elsevier, 2005.

610 • CHAPTER 51
Approaches to the scaphoid can be made either volarly
or dorsally. A volar approach is best used for distal pole
fractures, or in the presence of a fl exion or “humpback”
deformity of the scaphoid, allowing access to the distal
pole for reduction. A dorsal approach is preferable for
proximal pole fractures, or in the setting of concomitant
ligamentous injury to the wrist, such as a trans-scaphoid
perilunate injury.
Additionally, any scaphoid fracture that fails to unite,
either through failure of appropriate therapy, patient
neglect, or missed diagnosis, is likely to require surgical
intervention. Given the absence of connection to the
proximal carpal row when the fracture is distal to the
insertion of the dorsal intercarpal ligament, the distal
pole tends to progressively fl ex in the setting of a non-
union, resulting in the aforementioned “humpback” defor-
mity. This will often require a structural bone graft placed
volarly to extend the distal fragment. Bone grafts can take
the form of vascularized or nonvascularized, depending
on the length of nonunion and vascularity of the proxi-
mal pole. For this reason, an MRI may be of value for
preoperative planning. The most convenient site for non-
vascularized structural graft is the ipsilateral distal radius.
Local pedicled vascularized bone grafts may be obtained
from the volar and dorsal radius, while increasing interest
has been given to free bone fl aps from the medial femoral
condyle.
Scaphoid nonunion occurs in approximately 5% to
10% of fractures, with a higher incidence in fractures
of the proximal pole. If left uncorrected, these injuries
lead to a predictable progression of carpal degeneration
known as a scaphoid nonunion advanced collapse. This
can result in signifi cant pain, stiffness, and functional
loss. Surgical salvage procedures to treat this disorder
are limited (ie, proximal row carpectomy, scaphoid exci-
sion/midcarpal fusion, scaphoid distal pole excision) and
have signifi cant drawbacks. For this reason, much effort
is directed at successful identifi cation and treatment of
these fractures acutely.
Fractures of the Triquetrum
Fractures of the triquetrum come in three types. Dorsal
cortical fractures occur through a variety of mechanisms,
including avulsion, shear, and impaction. These fractures
can often be treated conservatively with 4 to 6 weeks of
immobilization. However, given the insertion of the dorsal
intercarpal and dorsal radiotriquetral ligaments in this area,
care must be taken to rule out an associated carpal insta-
bility. In the absence of carpal instability, these fractures
typically result in pain free recovery and remain asymp-
tomatic, even if resulting in nonunion.
Fractures of the triquetral body can occur in isolation or
in conjunction with perilunate injuries. If in isolation, they
are typically non-displaced and can be treated conserva-
tively with 4 to 6 weeks of immobilization.
Volar cortical fractures, like their dorsal counterparts,
can be an indication of carpal instability through disrup-
tion of the palmar ulnar triquetral ligaments or the inter-
carpal lunotriquetral ligament. Given the location of these
injuries, they are often missed on initial x-ray evaluation,
and advanced imaging should be pursued based on physi-
cal exam and clinical suspicion.
Fractures of the Trapezium
As with the triquetrum, fractures of the trapezium tend to
come in three forms. Marginal trapeziometacarpal fractures
typically result from acute instability of the thumb CMC
joint. Treatment decisions are directed to the subluxation/
dislocation, with the marginal fracture rarely needing to be
addressed directly.
Fractures of the trapezium body result from force trans-
mission longitudinally through the thumb metacarpal or
through thumb hyperextension. In displaced fractures, the
fracture line tends to extend into the distal articular sur-
face, and care must be directed at restoring articular con-
gruity to prevent post-traumatic arthrosis. A CT scan may
provide useful information about the fracture pattern or
articular alignment.
Trapezial ridge fractures can be divided into two types
and typically result from direct injury or avulsion of the
fl exor retinaculum. Type I injuries occur at the base and
typically heal with immobilization. Type II injuries, repre-
senting the trapezial tip, often go on to nonunion and can
be excised if symptomatic. These injuries typically require
a CT scan, carpal tunnel x-ray view, or a Betts view (thumb
extended/abducted, hand pronated, hypothenar eminence
resting on plate, beam directed at scaphotrapeziotrapezoi-
dal joint for detection).
Fractures of the Hamate
The most recognizable fractures of the hamate are those
involving the hamular process, or hook of the hamate.
These are common injuries in club/racquet sports, such as
golf, tennis, squash, and baseball. Patients typically present
with deep ulnar-sided wrist pain. Because the hook of the
FIGURE 51-8. Scaphoid waist fracture stabilized with a
differentially threaded screw. Note the compression across the
fracture site. This screw was implanted through a minimally
invasive approach, limiting additional trauma to the fragile
blood supply of the scaphoid.

FRACTURES OF THE HAND AND WRIST • 611
hamate acts as a pulley for the fl exor tendons in ulnar devi-
ation, resisted small fi nger fl exion in this position should
elicit pain. If clinical suspicion exists, these injuries can
often be better elucidated on a carpal tunnel x-ray view,
CT scan, or MRI ( Figure 51-9 ).
The treatment of acute hook fractures involves immo-
bilization. Due to the poor blood supply of this region
nonunion is a common sequelae. If symptomatic, these
injuries may be addressed with a hook excision or ORIF
with or without bone grafting. The former option results
in limited functional loss and prevents a host of potential
complications that may accompany ORIF. Given the posi-
tion of the hook of the hamate in Guyon canal, fractures
can result in nerve injury to the ulnar nerve or ulnar artery.
In a chronic setting, fl exor tendon rupture can result from
friction against the fractured surface.
Fractures of the body of the hamate are typically
oblique and tend to extend radial to the hook of the
hamate. They are often stable and respond well to a short
period (4–6 weeks) of immobilization. If intra-articular,
they commonly exit between the facets of the ring fi nger
and small fi nger metacarpals. In the setting of signifi cant
displacement or CMC instability, open reduction and
K-wire stabilization may be required.
Fractures of the Lunate
Fractures of the lunate have been catalogued by Teisen
and Hjarbaek, who described fi ve different types of frac-
ture in a series of 17 patients. 12 Because of the important
ligaments and nutrient vessels that attach to the palmar
pole, fractures of this region should be fi xed to prevent the
development of carpal instability or avascular necrosis. Like
the scaphoid, the blood supply of the lunate is somewhat
tenuous, and avascular necrosis can result. This should not
be confused with Kienbock disease, or idiopathic avascular
necrosis of the lunate.
Fractures of the Pisiform
Fractures of the pisiform most commonly result from
a direct blow to the hypothenar space but have been
described after repetitive trauma. A CT scan or special
x-ray views, such as a supination oblique or carpal tun-
nel view, may be necessary for their diagnosis. Because
almost half of all pisiform fractures occur in conjunc-
tion with other upper extremity injuries, they are often
missed during the initial survey. Late sequelae of pisiform
fractures include nonunion and pisotriquetral arthritis. In
this instance, pisiform excision provides fairly predictable
relief without signifi cantly compromising wrist function.
Because of the proximity of the pisiform to Guyon canal,
careful evaluation of ulnar nerve function must accom-
pany any documented injury.
Fractures of the Capitate
Fractures of the capitate are often nondisplaced and local-
ized to the body. They are said to represent approximately
1% of all carpal fractures, but with the increased use of
MRI for evaluation of the scaphoid, the incidence of these
injuries is increasing. If a capitate fracture is diagnosed, a
careful examination of the stability of the wrist must ensue,
as 50% of capitate fractures are associated with concomi-
tant ligamentous and bony injury. 13
The proximal portion of the capitate is completely intra-
articular, resulting in limited blood supply. Waist fractures,
therefore, can lead to nonunion and avascular necrosis of
the proximal pole. Even with treatment, whether by bone
grafting, midcarpal fusion, or excision arthroplasty, persis-
tent symptoms are common.
Fractures of the Trapezoid
Fractures of the trapezoid are the least common of all car-
pal fractures due to the stout ligamentous protection pro-
vided by its relationship to the trapezium, capitate, and
index metacarpal. Fractures are typically the result of an
indirect force directed through the index metacarpal and
can be associated with carpometacarpal or axial pattern
dislocations. Basic fracture principles apply to these inju-
ries, with large or displaced fractures requiring stabiliza-
tion and small or nondisplaced fractures being adequately
treated by conservative means.
COMPLICATIONS
Fractures of the hand and wrist are susceptible to the
same complications as fractures in other areas of the body.
Malunion is a common complication that often results
FIGURE 51-9. MRI of a 28-year-old golfer with chronic ulnar-sided wrist pain. This
nondisplaced hook of the hamate fracture was successfully treated with immobilization
and activity modifi cation.

612 • CHAPTER 51
from delayed presentation or closed treatment of dis-
placed fractures. While signifi cant deformity can be toler-
ated in the some settings (ie, small fi nger metacarpal neck
fractures), it is less acceptable in the phalanges or carpal
bones. Therefore, it is paramount for treating physicians to
understand the kinematics of the hand and wrist to deter-
mine what constitutes an adequate reduction.
Nonunion can occur in many locations, but are most
frequently encountered in open fractures with signifi cant
soft tissue stripping, or in areas known to have poor blood
supply, such as the scaphoid. Treatment can consist of sta-
bilization (in the setting of failed conservative care), non-
vascularized bone grafting, or vascularized bone grafting.
As previously discussed, the distal radial metaphysis is a
good source of local nonvascularized autograft for non-
unions of the hand and wrist.
Avascular necrosis is a rare complication that can result
either from the initial injury or from surgical treatment.
As with nonunions, this is typically of concern in areas of
known poor vascularity. Care must be taken by the sur-
geon intraoperatively to respect the soft tissue envelope
and avoid further vascular insult during surgical stabili-
zation. Avascular fragments in the hand typically require
excision, with management of the remaining void based
on size and location of the defect. Avascular fragments of
the carpus may also be treated with excision, but should
be considered for vascularized bone grafting. The longevity
of the condition and status of the surrounding articulations
are important factors in assessing salvage options.
In fractures treated surgically, hardware complica-
tions, including loss of fi xation, symptomatic hardware,
and hardware failure, are introduced as possible com-
plications. Surgeons must ensure stable constructs with
tolerable hardware, using low-profi le designs and coun-
ter-sinking where appropriate. Infection can also result
from injuries treated in an open fashion, so pre-operative
antibiotics should be administered whenever implant use
is anticipated.
The most frequently battled complication of hand
and wrist fracture management is stiffness. An excellent
radiographic result may belie a poor functional result.
Consideration of the benefi ts of aggressive fracture man-
agement (stable fi xation, anatomic reduction, early mobi-
lization) must always be weighed against the risks of soft
tissue and joint contracture and stiffness.
OUTCOMES ASSESSMENT
Given the broad range of injuries presented in this chap-
ter, and the signifi cant variability that can be associated
with each, it is diffi cult to make defi nitive statements
about patient outcomes. However, several general princi-
ples do apply. In the hand, long-term satisfaction is strongly
related to rotational alignment and joint motion. With
that in mind, some tolerance of angular malalignment is
acceptable, while tolerance of rotational malalignment
is extremely limited. Treatment decisions should always
include a consideration for rehabilitation of the injured
hand. Typically, the most minimally invasive solution that
will still allow early motion is the best choice.
Regarding the carpus, it is essential to recognize
that many seemingly isolated injuries may be part of a
broader injury pattern. Therefore, care must be taken
to assess the overall alignment and stability of the wrist
when an injury is identifi ed. The anatomy of the carpus
makes complete evaluation by standard x-rays diffi cult,
so a treating physician must have a full understanding of
specialized x-ray views and know when to apply them. A
low threshold for advanced imaging will also help avoid
missing injuries.
REFERENCES
1. Amadio PC, Moran SL. Fractures of the carpal bones. In:
Green DP, Hotchkiss RN, Pederson WC, Wolfe SW, eds.
Green’s Operative Hand Surgery. 5th ed. Philadelphia:
Churchhill Livingstone; 2005:711–768.
2. Stern PJ. Fractures of the metacarpals and phalanges. In:
Green DP, Hotchkiss RN, Pederson WC, Wolfe SW, eds.
Green’s Operative Hand Surgery. 5th ed. Philadelphia:
Churchill-Livingstone; 2005:277–341.
3. Steel WM. The A.O. small fragment set in hand fractures.
Hand. 1978;10:246–253.
4. Strickland JW, Steichen JB, Kleinman WB. Phalangeal frac-
tures: Factors infl uencing digital performance. Orthop Rev.
1982;11:39–50.
5. Weiss AP, Hastings H. Distal unicondylar fractures of the
proximal phalanx. J Hand Surg Am. 1993;18:594–599.
6. Stern PJ, Roman RJ, Kiefhaber TR, McDonough JJ. Pilon
fractures of the proximal interphalangeal joint. J Hand Surg
Am. 1991;16:844–850.
7. Williams RM, Hastings H, Kiefhaber TR. PIP Fracture/
Dislocation Treatment Technique: Use of a Hemi-Hamate
Resurfacing Arthroplasty. Tech Hand Up Extrem Surg.
2002;6:185–192.
8. Foucher G. “Bouquet” osteosynthesis in metacarpal neck
fractures: a series of 66 patients. J Hand Surg. 1995;20A:
S86–S90.
9. Timmenga EJ, Blokhuis TJ, Maas M, Raaijmakers EL.
Long-term evaluation of Bennett’s fracture. A compari-
son between open and closed reduction. J Hand Surg.
1994;19:373–377.
10. Kozin SH. Incidence, mechanism, and natural history of
scaphoid fractures. Hand Clin. 2001;17:515–524.
11. Gaebler C, Kukla C, Breitenseher M, Trattnig S, Mittlboeck
M, Vecsei V. Magnetic resonance imaging of occult scaphoid
fractures. J Trauma. 1996;41:73–76.
12. Teisen H, Hjarbaek J. Classifi cation of fresh fractures of the
lunate. J Hand Surg Br. 1988;13:458–462.
13. Shah MA, Viegas SF. Fractures of the carpal bones excluding
the scaphoid. J Am Soc Surg Hand. 2002;2:129–140.

c h a p t e r52
Management of Hand Infections
Suhail Kanchwala, MD / Benjamin Chang, MD, FACS
GENERAL PRINCIPLES
Infections of the hand can lead to signifi cant patient mor-
bidity, including pain, disability, lost time, and productivity
at work. The sequelae of acute and chronic hand infections
can be devastating to the patient. In addition, infections
in the hand can be the presenting symptom in a number
of systemic illnesses. As a result, the prompt and accu-
rate diagnosis of surgical infections in the hand is critical
for minimizing disability and facilitating a rapid recovery
( Table 52-1 ).
Early surgical intervention plays a critical role in the
treatment of hand infections. Evaluation of a hand infec-
tion should include an assessment of depth of infection,
presence of pus, degree of erythema, and range of motion
of the affected digits. In addition, a thorough medical his-
tory should be obtained with emphasis on those factors
that affect the ability of the patient to ward off infection
(diabetes, HIV, immunosuppression).
The anatomy of the hand, with numerous fascial com-
partments, allows the infl ammatory response to infection
itself to become pathogenic. For example, excessive swell-
ing in the hand can result in increased pressure on tendons
in the fi ngers and palm leading to ischemia and tendon
necrosis.
Early infections in the hand, regardless of location, can
be managed initially by a period of rest, elevation, antibiot-
ics, close observation, and splinting in the safe position. For
those infections that have progressed or whose initial pre-
sentation indicates the presence of an abscess (ie, fl uctu-
ance and drainage), the defi nitive treatment must include
adequate surgical drainage and debridement of devitalized
tissues. In those cases where there may be a delay in taking
the patient to the operating room for debridement, the
abscess cavity should be aspirated to reduce compartment
pressures and the risk of tendon and neurovascular
structure injury.
Empiric antibiotics that are designed to cover the most
likely pathogens for each type of infection should be started
after wound cultures have been obtained. However, anti-
biotics are not a substitute for adequate surgical drainage
and debridement. Infections in the hand are often polymi-
crobial—a critical consideration when making a selection
of empiric antibiotic therapy. 1 All wounds that are a result
of exposure to soil, animals, or the oral cavity (ie, human
bite wounds) should be appropriately treated with tetanus
prophylaxis.
Surgical intervention in patients with hand infections can
often be performed using regional anesthetic techniques.
However, the infi ltration of local anesthesia directly into
an area of cellulitis or infection is ill-advised. For example,
fi ngertip infections can be managed with digit blocks, but
deep space infections of the hand should be drained under
either general anesthesia. The use of the operative tourni-
quet is crucial to avoid excessive bleeding which can impair
visualization. When using the tourniquet with infection,
the extremity should be exsanguinated by elevation and
gravity, rather than the use of an elastic band to avoid the
potential spread of the infection ( Figure 52-1 ).
ACUTE PARONYCHIA
Paronychia, or runaround infections of the fi ngertip, are
infections of the soft tissue fold surrounding the nail
plate, typically with staphylococcal species. Risk factors
for paronychial infection include hangnails, nail biting,
manicures, and poor hand hygiene. Hallmarks of parony-
chial infection include pain, swelling, and erythema in the
perionychium.

614 • CHAPTER 52
Initial management of paronychial infections include
warm soaks and oral antibiotics. When paronychial infec-
tions lead to abscess formation within the eponychial fold
or under the nail plate, surgical drainage is necessary. When
performing an incision and drainage of a paronychia, it is
important to angle the blade away from the nail bed to
avoid inadvertent damage to the nail bed and subsequent
ridging of the nail.
When the area of abscess formation is under the nail
plate it is important to remove the nail to allow adequate
drainage of the abscess. Again, the key to the prevention of
nail abnormalities following successful drainage is to mini-
mize the trauma to the nail bed ( Figure 52-2 ).
HERPETIC WHITLOW
Commonly confused with paronychial infections,
herpetic infections of the hand typically involve the
fi ngertip and soft tissues surrounding the nail plate.
While herpetic infections may mimic bacterial infections
TABLE 52-1. Common Hand Infections, Usual Offending Organisms, and
Appropriate Therapeutic Regimens
Condition
Most Common
Offending Organisms
Recommended Antimicrobial Agents
Comments
Paronychia
Usually Staphylococcus
aureus or
streptococci;
Pseudomonas , gram-
negative bacilli, and
anaerobes may be
present, especially in
patients with exposure
to oral fl ora
First-generation cephalosporin or anti-
staphylococcal penicillin; if anaerobes
or Escherichia coli are suspected,
oral clindamycin (Cleocin) or a beta-
lactamase inhibitor such as amoxicillin-
clavulanate potassium (Augmentin)
Incision and drainage should be
performed if infection is well
established.
If infection is chronic, suspect
Candida albicans.
Early infections without cellulitis
may respond to antibiotics alone.
Felon
S. aureus , streptococci
First-generation cephalosporin or anti-
staphylococcal penicillin
Incision and drainage should be
performed if infection is well
established.
Herpetic
whitlow
Herpes simplex virus
types 1 and 2
Supportive therapy
Antivirals may be prescribed if
infection has been present for
,48 hours.
For recurrent herpetic whitlow,
suppressive therapy with an
antiviral agent may be helpful.
Consider antibiotics if secondarily
infected.
Incision and drainage are
contraindicated.
Pyogenic fl exor
tenosynovitis
S. aureus , streptococci,
anaerobes
Parenteral fi rst-generation cephalosporin
or antistaphylococcal penicillin and
penicillin G
or
Parenteral beta-lactamase inhibitor such
as ampicillin-sulbactam (Unasyn)
Use ceftriaxone (Rocephin) or
a fl uoroquinolone if Neisseria
gonorrhoeae is suspected
Early surgical assessment is
suggested.
N gonorrhoeae or C albicans should
be suspected in sexually active or
immunecompromised patients.
Incision and drainage with catheter
irrigation of the sheath should
be performed if no improvement
within the fi rst 12 to 24 hours of
conservative therapy.
Human bite,
clenched-fi st
injury
S. aureus , streptococci,
Eikenella corrodens ,
gram-negative bacilli,
anaerobes
Parenteral fi rst-generation cephalosporin
or antistaphylococcal penicillin and
penicillin G
or
Beta-lactamase inhibitor such as
ampicillin-sulbactam or amoxicillin-
clavulanate potassium
or
Second-generation cephalosporin such
as cefoxitin (Mefoxin)
Prophylactic oral antibiotics should
be used if outpatient therapy is
chosen.
Wounds should be explored,
copiously irrigated, and surgically
debrided.
Hospitalization and parenteral
antibiotics often are indicated.

MANAGEMENT OF HAND INFECTIONS • 615
of the hand in many ways, they can usually be distin-
guished from bacterial infections by an adequate history
and examination.
Herpetic infections in children and health care work-
ers (dentists, respiratory therapists, etc.) are most often
the result of viral inoculation from the oropharynx by the
herpes simplex virus type 1 (HSV-1). In adults, however,
HSV-2 predominates and is most often due to inoculation
from genital herpes. Herpetic infections typically have an
incubation period of 2 weeks, after which patients experi-
ence pain and mild swelling in the affected digit. Following
this period, small 1–2 mm vesicles erupt in the affected
digits. These vesicles then coalesce to form large bullae.
A Tzanck smear test is diagnostic. 2
The management of herpetic hand infections does
not involve surgery unless there is bacterial superinfec-
tion. In fact, surgical intervention in cases of herpetic
whitlow because of a misdiagnosis can lead to systemic
FIGURE 52-2. (A) An acute paronychia in the emergency room. (B) Incise through
most fl uctuant region.
A
B
FIGURE 52-1. (A) A patient with large subcutaneous abscess in the fi rst web space.
(B) Wide surgical debridement is essential.
A
B

616 • CHAPTER 52
spread. 3 Viral infection of the hand can lay dormant in
the nervous system for many years and then reactivate
( Figure 52-3 ).
Chronic paronychia is a distinct clinical entity from
acute paronychia. Chronic infl ammation of the soft tis-
sues surrounding the nail plate can lead to repeated epi-
sodes of erythema, pain, and drainage from the infected
region. Patients who have repeated exposure to water
(waiters, dishwashers, etc) are at highest risk for develop-
ment of this chronic infl ammation. Streptococcus pyogenes ,
Staphylococcus epidermidis , and Candida are the most com-
mon causes of chronic paronychia.
The treatment of chronic paronychia involves the exci-
sion of a minimum 3 mm wide crescent of skin and sub-
cutaneous tissue parallel to the eponychial fold running
the entire width of the fi nger. This procedure is referred
to as eponychial marsupialization. The wound is then
left open for drainage and the patient is placed on a regi-
men of hand soaks in a variety of solutions such as dilute
povidone-iodine. The warm soaks are continued until
the infl ammation/drainage has ceased. Nail irregulari-
ties caused by chronic paronychia can be treated by the
removal of the entire nail. 4 As long as the eponychial fold
is appropriated stented, the nail should regrow without
abnormalities assuming the paronychia has been treated
appropriately.
FELON
A felon is an infection in the soft tissue pulp on the volar
aspect of the fi ngertip. The distal fi nger pad is an ana-
tomically distinct structure from the rest of the fi nger.
Numerous fi brous septae attach the dermis of the distal
fi nger pad directly to the underlying bone, allowing the
fi ngertip to be used for essential functions such as grasp. If
a signifi cant number of these septae are disrupted during
draining of a felon, a mobile, nonfunctional fi ngertip can
result. 5
Surgical management of the felon requires antibiot-
ics and adequate incision and drainage. In order to pre-
serve fi ngertip sensibility and perfusion, we advocate the
use of a volar incision, directly over the point of maxi-
mal fl uctuance. Incisions should not be carried over the
joint fl exion crease to minimize postoperative contracture
( Figure 52-4 ).
PYOGENIC TENOSYNOVITIS
Pyogenic tenosynovitis is a closed space infection of the
fl exor tendon sheath of the fi ngers or thumb. The most
common cause of this infection is penetrating injury to
the proximal interphalangeal or distal interphalangeal
joint on the volar surface. The fl exor tendon sheath can
FIGURE 52-3. Herpetic whitlow.
FIGURE 52-4. (A) Felon. (B) All necrotic tissue must be excised.
A
B

MANAGEMENT OF HAND INFECTIONS • 617
be compromised by foreign bodies or even teeth (as in the
case of a human or animal bite). Rarely, pyogenic teno-
synovitis is spread to the fi ngers from a distant source, such
as disseminated gonorrheal infection. The most common
organisms cultured from patients with pyogenic tenosyno-
vitis are Staphylococcus aureus and beta-hemolytic strepto-
coccal species.
Pyogenic tenosynovitis can be extremely disabling
because infections in the tendon sheath interrupt the nor-
mal gliding mechanism of the fl exor tendons. Late recogni-
tion and treatment of this disorder can result in fi brosis, or
tendon necrosis and permanent loss of function.
Hallmarks of this infection include the following clini-
cal signs that were initially postulated by Kanavel: 6
1. Semi-fl exed fi nger position
2. Symmetrical enlargement of the whole digit
3. Excessive tenderness limited to the course of the fl exor
tendon sheath
4. Pain on passive extension of the fi nger
The management of pyogenic tenosynovitis involves ade-
quate drainage and irrigation of the tendon sheath. A vari-
ety of drainage procedures have been advocated. There is a
consensus that copious irrigation of the tendon sheath with
minimized exposure of the tendon itself through carefully
placed incisions leads to fewer postoperative complica-
tions secondary to adhesion formation within the fl exor
sheath ( Figure 52-5 ). 7
DEEP SPACE INFECTIONS
Deep space infections of the hand can be broken down
into three general regions: the palmar, thenar, and Parona
spaces. The thenar eminence is the most common region
for deep space infections to occur. These occur most com-
monly as direct puncture wound to the region or from
nearby infection of the tendon sheath.
Deep space infections in the hand have decreased in
frequency as a result of earlier management of localized
infections in the hand (eg, pyogenic tenosynovitis of the
fi ngers) and treatment with antibiotics.
Management includes incision and drainage of the
region. Placement of the incisions depends on the locations
of the abscesses: middle space infections—curvilinear from
distal palmar crease to hypothenar eminence; thenar—
curvilinear along thenar crease (avoid recurrent branch of
median nerve).
COLLAR BUT TON ABSCESS
Commonly seen in laborers, collar button or web space
abscesses are hand infections beneath palmar calluses that
localize to one of the three web spaces. Since the dorsal skin
is more compliant than the palmar skin, swelling and fl uctu-
ance from collar button abscesses are often greater dorsally.
Complete drainage of these abscesses often requires inci-
sions both dorsally and on the palmar surface. 8 The fail-
ure to recognize the extent of the infection on the palmar
surface can lead to incomplete drainage and spread of
the infection to the deep palmar space. It is important
to avoid damage to the web itself to avoid contractures
postoperatively.
RADIAL AND ULNAR
BURSA INFECTIONS
Knowledge of the anatomy of the radial and ulnar bursae
of the hand are critical to understanding the development
of bacterial infections in this region. The radial bursa is
the proximal extent of the fl exor sheath of the thumb,
while the ulnar bursa includes the fl exor sheath of the lit-
tle fi nger and just the sheath of the second to fourth meta-
carpal fl exor tendons in the palm. The Parona space (the
potential space between pronator quadratus and the fl exor
tendons) serves as a bridge between the radial and ulnar
bursae and allows the formation of “horseshoe” abscesses.
When draining abscesses in the Parona space, it is particu-
larly important to avoid injuring the median nerve and its
palmar cutaneous branch.
HUMAN BITES
Human bite injuries can lead to some of the most com-
plex of all the common hand infections. Typically, human
bite injuries occur through clenched fi st injuries where
the patient’s fi st strikes an opponent’s tooth, piercing the
metacarpophalangeal joint. The initial puncture wound
may look innocuous but leads to a septic joint in days. Most
FIGURE 52-5. Pyogenic fl exor tenosynovitis.

618 • CHAPTER 52
of these infections are polymicrobial and have a wide range
of possible pathogens due to the high number of bacte-
rial species present in the human mouth. 9 Skin fl ora and
Eikenella species are the most common organisms isolated.
Additionally, this patient population is often noncompli-
ant and there is also a signifi cant delay in seeking medical
attention. 10
The management of human bite injuries includes
admission, x-rays to evaluate foreign bodies and fractures,
exploration in the operating room, and empiric antibiotics.
Superfi cial abrasions and infections can be managed with
antibiotics and close observation. If the extensor mecha-
nism has been penetrated, or the depth of penetration can-
not be determined, the wound should be explored in the
operating room.
The management of animal bites (eg, dog and cat) is
quite similar to that of human bites. Prophylaxis with
tetanus is paramount. Dog and cat bites tend to be less
polymicrobial than human bites; and cat bites have a high
likelihood of Pasteurella multocida infection. Of the two,
cat bites are more likely to become infected because the
puncture wound is small and seals quickly.
SEPTIC ARTHRITIS
Finger joint infections are typically the result of the spread
of infection from local tissues and less commonly the result
of hematogenous spread to the joint spaces. Symptoms of
a septic joint include swelling, fl uctuance, and warmth
which is usually held in slight fl exion and have pain on
even slight passive movement of the joint.
Joint aspiration is an important diagnostic tool and will
typically reveal a purulent/cloudy fl uid:
1. Gram stain .50,000 WBC
2. .75% polymorphonuclear cells
3. Fluid glucose #40 mg
Once pus is identifi ed in the joint, it is a surgical emer-
gency. Rapid and adequate irrigation and debridement is
essential to minimize the cartilage and joint destruction
that can result from septic arthritis. Cultures should be
obtained prior to starting antibiotics, and empiric therapy
initiated, based on the Gram stain results.
OSTEOMYELITIS
Osteomyelitis of the hand is typically the result of pen-
etrating trauma or open fractures in the hand. The degree
of damage to the soft tissues overlying the affected bone
plays a signifi cant role in the development and patho-
genesis of osteomyelitis. Direct spread from a soft tissue
infection such as pyogenic tenosynovitis is a rare cause of
osteomyelitis.
The diagnosis of osteomyelitis can be made after a
thorough history identifying risk factors as well as radio-
graphic analysis starting with x-rays and often includ-
ing nuclear medicine imaging (bone scan, tagged white
blood cell scan) as well as magnetic resonance imaging
of the hand.
The management of osteomyelitis depends on the sever-
ity of the presenting complaint/disability and the duration
of infection. Early infections with minimal complaints may
be cautiously managed with intravenous antibiotics alone.
However, most often, in order to achieve adequate resolu-
tion of the infection, surgical debridement is mandated. 11
When a sequestrum is present, curettage of all necrotic
bone is essential and the wound should be packed open.
Should a bone defect be present after debridement, recon-
struction should only be considered after clearance of
infection ( Figure 52-6 ).
NECROTIZING FASCIITIS
Necrotizing fasciitis is a limb and potentially life-threat-
ening infection that is often caused by minor of trauma
to the affected extremity. Hallmarks of necrotizing fas-
ciitis in the upper extremity include bright, shiny skin,
nonpitting edema, poorly demarcated redness, and skin
discoloration and necrosis. Patients who are diabetic or
immunocompromised have a much higher risk of con-
tracting necrotizing fasciitis. A single organism is found
FIGURE 52-6. (A) Osteomyelitis from untreated paronychia. (B) Note the resorbed
distal phalanx epiphysis.
B
A

MANAGEMENT OF HAND INFECTIONS • 619
as the causative agent in nearly 50% of cases, most often
group A beta-hemolytic streptococcal species (occasion-
ally S aureus ). 12
Because the mortality of this infection can be as high as
40%, early and aggressive surgical intervention and debri-
dement is mandatory. Early empiric treatment with broad-
spectrum antibiotics, even before cultures have been
obtained, can signifi cantly decrease the morbidity of this
infection. Depending on the degree of infection and soft
tissue damage, multiple debridements and even amputa-
tion may be necessary.
IV DRUG ABUSE
The direct inoculation of bacteria into the subcutaneous
tissues by IV drug use can lead to the rapid formation of
abscesses. In addition to the introduction of bacteria, the
injectate itself can lead to local tissue necrosis. The most
common causative agents are staphylococcal and strep-
tococcal species. These infections are polymicrobial and
present many challenges to treatment.
Appropriate management involves rapid and adequate
debridement and antibiotic therapy. Repeated debri-
dements may be necessary. Despite adequate drainage,
recurrent abscesses are not uncommon. Large abscesses
can be effectively drained through multiple small inci-
sions along the periphery of the cavity. Penrose drains
are threaded through these incisions, across the cavity,
to maintain drainage until purulence resolves (2–3 days)
( Figure 52-7 ).
NOSOCOMIAL INFECTIONS
Due to the enhanced vascularity of the hand, postop-
erative infections are quite rare. The routine use of pro-
phylactic antibiotics in clean, routine hand cases is not
recommended. The most common causative organism for
hand infections secondary to surgery is S aureus . Routine
use of perioperative antibiotics is recommended for those
operations involving bone or joint spaces.
TREATMENT OF RESISTANT
ORGANISM INFECTION
There has been a dramatic increase in the number of
patients who are admitted to hospital with nosocomial
methicillin-resistant S aureus (MRSA) wound infections in
the past decade. This trend has been seen in the outpatient
setting as well. Karanas et al. reported a case series of four
patients with community-acquired MRSA hand infections
who had no previous risk factors for MRSA infection (eg,
diabetes, IV drug use, catheter-related infections). 13 The
emergence of resistant organisms will predictably play a
large role in the management of future infections.
The increase in resistant infections underscores the
importance of routine wound culture prior to initiating
antibiotic therapy, whenever possible, to guide antibi-
otic therapy. Many institutions publish hospital-specifi c
guidelines for empiric antibiotic coverage which accounts
for individual drug resistance patterns. 14 , 15 These guides
should be consulted prior to the initiation of empiric anti-
biotic therapy.
FIGURE 52-7. (A) Large subcutaneous abscess from intravenous drug abuse.
(B) The use of multiple small incisions and Penrose drains to manage a large loculated
abscess.
A
B

620 • CHAPTER 52
REFERENCES
1. Wright PE II. Hand infections. Canale ST, ed. Campbell’s
Operative Orthopedics . 9th ed. St. Louis, MO: Mosby; 1998.
2. Louis DS, Silva J Jr. Herpetic whitlow: herpetic infections of
the digits. J Hand Surg. 1979;4(1):90–94.
3. Clark DC. Common acute hand infections. Am Fam Physi-
cian . 2003;68(11):2167–2176.
4. Grover C, Bansal S, Nanda S, et al. En bloc excision of proxi-
mal nail fold for treatment of chronic paronychia. Dermatol
Surg. 2006;32(3):393–398; discussion 398–399.
5. Connolly B, Johnstone F, Gerlinger T, Puttler E. Methicillin-
resistant Staphylococcus aureus in a fi nger felon. J Hand
Surg Am. 2000;25(1):173–175.
6. Kanavel, AB. Infections of the Hand; A Guide to the Surgi-
cal Treatment of Acute and Chronic Suppurative Processes in
the Fingers, Hand and Forearm . Philadelphia: Lea & Febiger;
1912.
7. Boles SD, Schmidt CC. Pyogenic fl exor tenosynovitis. Hand
Clin . 1998;14:567–578.
8. Brenman, S. Hand infections and related extremity injury.
In: Georgiade GS, Georgiade NG, Riefkohl R, Barwick WJ,
eds. Textbook of Plastic, Maxillofacial and Reconstructive
Surgery . Baltimore, MD: Williams & Wilkins; 1987:
1222–1223.
9. Chuinard RG, D’ambrosia RD. Human bite infections of the
hand. J Bone Joint Surg . 1977;59a(3):416–418.
10. Zubowicz VN, Gravier M. Management of early human bites
of the hand: a prospective randomized study. Plast Reconstr
Surg. 1991;88:111–114.
11. Dormans JP. Hand infections. In: Pediatric Orthopaedics and
Sports Medicine. Philadelphia: Mosby; 2004.
12. Bisno AL, Stevens DL. Streptococcal infections of skin and
soft tissues. N Engl J Med . 1996;334(4):240–245.
13. Karanas YL, Bogdan MA, Chang J. Community acquired
methicillin-resistant Staphylococcus aureus hand infections:
case reports and clinical implications. J Hand Surg Am .
2000;25(4):760–763.
14. Moran GJ, Krishnadasan A, Gorwitz RJ, et al. Methicillin-
resistant S. aureus infections among patients in the emer-
gency department. N Engl J Med . 2006;355(7):666–674.
15. Bug Drug Web site. .

53
Compressive Neuropathies
in the Upper Extremity
David J. Slutsky, MD
INTRODUCTION
A neuropathy may be defi ned as any disorder that results
in abnormal nerve function. Neuropathies can be general-
ized and are as such frequently associated with a number
of systemic disorders such as diabetes, hypothyroidism,
alcoholism, vitamin B12 defi ciency, and lead poisoning.
The neuropathy may be focal or restricted to a specifi c
anatomical location. Many of these focal neuropathies
arise due to nerve compression, although traction plays a
signifi cant role.
In early nerve compression, the symptoms are of a vas-
cular nature. Fluid shifts that occur with limb position
result in endoneurial edema. The absence of lymphatic
drainage from the endoneurial space makes the clear-
ance of edema slow. The edema cuts off the blood supply
by pinching off the arterioles which course through the
perineurium obliquely. This impairs the ATP-dependent
ion exchange pump. This ultimately results in a reversible
metabolic conduction block, which leads to paresthesia.
Chronic compression leads to infl ammation and secondary
fi brosis, which disrupts this gliding layer, ultimately lead-
ing to nerve tethering. Any compressive neuropathy there-
fore frequently has a component of traction neuropathy as
well. Traction alone can cause conduction block.
NERVE ANATOMY
Median Nerve
The median nerve contains the nerve root fi bers from
C6-T1 and arises from the medial and lateral cords of
the brachial plexus. In the upper arm, it lies lateral to the
axillary artery but crosses medial to it at the level of the
coracobrachialis. At the elbow, it travels in front of the
brachialis and behind the bicipital aponeurosis. At dis-
tal part of the cubital fossa, the motor branches of the
median nerve consistently collect into three fascicular
groups. There is an anterior group (to the pronator teres
and fl exor carpi radialis [FCR]), middle group (motor to
the fl exor digitorum superfi cialis [FDS] and hand intrin-
sics; sensory to the thumb, index, and middle fi ngers), and
a posterior group (to the anterior interosseous branch).
The nerve and artery pass through the antecubital fossa
underneath the lacertus fi brosis and gives off branches to
the palmaris longus, FCR, FDS, and rarely the fl exor digi-
torum profundus (FDP). The nerve then dives between
the deep and superfi cial heads of the pronator teres to
which it supplies one to four branches. The fi brous arch
of the pronator teres lies 3.0 to 7.5 cm below the humeral
epicondylar line. The fi brous arch of the superfi cialis
arch lies 6.5 cm below the humeral epicondylar line. The
median nerve enters the forearm deep to the fi brous arch
of the FDS and emerges beneath the radial side of the
muscle belly of the middle fi nger superfi cialis where it is
quite superfi cial and near the palmaris longus tendon. The
anterior interosseous nerve (AIN) is the largest muscular
branch that emerges from the median nerve. It innervates
the FDP to the index and middle fi ngers, the FPL, and
the pronator quadratus. The terminal portion also pro-
vides sensory innervation to the carpal joints. The AIN
arises from the median nerve on the dorsoradial surface
about 5 to 8 cm distal to the medial epicondyle. The AIN
travels between the FDS and FDP, and then passes dor-
sally in the interval between the fl exor pollicus longus
c h a p t e r

622 • CHAPTER 53
(FPL) and FDP, giving off two to six branches to each of
these muscles. The nerve reaches the anterior surface of
the interosseous membrane and travels with the anterior
interosseous artery where it passes deep to the pronator
quadratus which it also innervates. It ends by sending sen-
sory afferent branches to the intercarpal, radiocarpal, and
distal radioulnar joints.
The carpal tunnel is open-ended proximally and dis-
tally, but behaves like a closed compartment physiologi-
cally and maintains its own distinct tissue fl uid pressure
levels. It is a fi bro-osseous canal that is bounded by the
concave arch of the carpal bones dorsally, and the fl exor
retinaculum palmarly. The hook of the hamate, tri-
quetrum, and pisiform form the ulnar border, while the
radial border consists of the scaphoid, trapezium, and the
fascial septum overlying the FCR. The fl exor retinaculum
consists of three zones: a proximal zone that is continu-
ous with the deep forearm fascia, a central zone which is
composed of the transverse carpal ligament (TCL), and a
third zone which consists of the aponeurosis between the
thenar and hypothenar muscles. The median nerve at the
wrist has approximately 30 fascicles. The motor recurrent
branch often consists of two fascicles, which are situated
in a volar position, with the various sensory groups in the
radial, ulnar, and dorsal positions. The motor branch can
be separated from the main trunk without harm for up
to 100 proximal to the thenar muscles. The sensory fi bers
travel within the common digital nerves to the thumb,
index and middle, as well as the communicating branch to
the third web space.
Median nerve compression neuropathies in the distal
arm and forearm are extremely uncommon when com-
pared with carpal tunnel syndrome (CTS). The more
proximal of the median nerve compression neuropathies is
the pronator syndrome. The syndrome is classically associ-
ated with any of four potential areas of compression: the
ligament of Struthers, the lacertus fi brosis, the aponeu-
rotic fascia of the superfi cial, or deep head of pronator
teres or the FDS arch. Both carpal tunnel syndrome and
AIN entrapment should be excluded. The nerve may be
compressed by the ligament of Struthers, which is rarely
associated with a supracondylar process. It spans the supra-
condylar process and medial epicondyle and creates an
arcade that contains the median nerve and brachial artery.
The ligament of Struthers has also been described in the
absence of an associated supracondylar process. In the fore-
arm, the median nerve can be compressed by the prona-
tor teres, the FDS arch or the bicipital aponeurosis. Rare
causes of compression include a persistent median artery,
the Gantzer muscle (accessory head of the FPL), and the
palmaris profundus.
Isolated AIN palsy accounts for less than 1% of all
upper extremity peripheral neuropathies. It is still uncer-
tain as to whether this syndrome is due to infl ammation or
compression ( Figure 53-1 ). The AIN may be compressed
by fi brous bands from the deep (most common) or super-
fi cial head of the pronator teres, the fi brous arcade of the
FDS, enlarged bursae or tumors, aberrant or thrombosed
vessels, an accessory bicipital aponeurosis, and fractures of
the forearm and distal humerus.
In the carpal canal, there are two potential sites of com-
pression anatomically. The fi rst is at the proximal edge of
the TCL, where compression may be produced by acute
wrist fl exion. This accounts for the positive Phalen test
FIGURE 53-1. Anterior interosseous nerve compression.
(A) Inability to perform the OK sign. (B) Needle placement
during EMG of the pronator quadratus. (C) Clinical photo at
8 months showing active fl exion of the distal phalanx of the
index but no active thumb IP joint fl exion. (Copyright David J.
Slutsky, with permission.)
A
B
C

COMPRESSIVE NEUROPATHIES IN THE UPPER EXTREMITY • 623
(wrist fl exion test) in CTS. The second is adjacent to the
hook of the hamate, where an hourglass deformity of the
median nerve may be seen. In this case, the patient will
have a positive median nerve compression (Durkan test)
but a negative Phalen test. Compression within the carpal
tunnel may also result from any lesion that takes up space
within the canal, such as fl exor tenosynovitis, hematoma,
palmar carpal dislocation, distal radius fractures, tumors,
and ganglia. Although many cases have been attributed to
a nonspecifi c synovitis, synovial biopsies typically fail to
show evidence of infl ammation. They do reveal edema and
vascular sclerosis, which may be secondary to compression
rather than the primary event.
Ulnar Nerve
The ulnar nerve contains the nerve root fi bers from C8-T1
and arises from the medial cord of the brachial plexus. It
provides the motor supply to the hypothenar muscles, the
ulnar two lumbricals, the interosseous muscles, the adduc-
tor pollicus, fl exor carpi ulnaris (FCU) and the profun-
dus to the ring and small fi ngers. Its sensory distribution
includes the palmar surface of the small and the ulnar half
of the ring fi nger as well as the dorsoulnar carpus. It lies
medial to the axillary artery and continues distally to the
mid-arm where it pierces the medial intermuscular sep-
tum The superior ulnar collateral artery often accompa-
nies the nerve. At the elbow, it lies between the medial
epicondyle and the olecranon where it is covered by the
Osborne ligament. It enters the forearm between the two
heads of the FCU covered by a fi brous aponeurosis (the
cubital tunnel). It runs deep to the FCU until the distal
forearm.
The ulnar tunnel or the Guyon canal is approximately
4 cm in length, which begins at the proximal edge of the
carpal transverse ligament and ends at the fi brous arch of the
hypothenar arch. It is bounded medially by the pisiform, and
radially by the hamate hook. The fl oor consists of the carpal
transverse ligament and the roof consists of the continuation
of the deep forearm fascia, ie, the volar carpal ligament. The
ulnar nerve has 15 to 25 fascicles at the wrist. It can be clearly
divided into a volar sensory component and a dorsal motor
component. At the wrist, the ulnar nerve passes over the
TCL, medial to the ulnar artery, through the Guyon canal.
The deep motor branch is given off at the pisiform and passes
underneath a fi brous arch to lie on the palmar surface of the
interossei. It crosses the palm deep to the fl exor tendons,
to terminate in the adductor pollicus and ulnar head of the
fl exor pollicis brevis.
The ulnar nerve may be compressed anywhere from
10 cm proximal to 5 cm distal to the medial epicondyle.
Ulnar nerve compression at the elbow is second only to
median nerve compression in the carpal tunnel as the
most common neuropathy in the upper limb. Five poten-
tial sites for compression have been described. The most
proximal site is the arcade of Struthers (different than
the ligament of Struthers), a fascial band that courses
obliquely over the ulnar nerve in the upper arm. The sec-
ond site is at the medial epicondyle when a cubitus val-
gus deformity is present. The third site is a fi bro-osseous
tunnel at the olecranon bounded anteriorly by the medial
epicondyle, laterally by the olecranon and ulnohumeral
ligament, and covered by a fi broaponeurotic band.
Compression at this site can be caused by lesions within
the groove such as tumors ( Figure 53-2 ), conditions out-
side the groove such as external compression or anoma-
lous muscles, and conditions that predispose the nerve
to displace from the groove. The fourth site is between
the two heads of the FCU muscle. The fl oor of the pas-
sageway through FCU is the medial collateral ligament
FIGURE 53-2. Anterolateral approach to PIN decompression. (A) Anterior approach
with a view of the proximal volar forearm demonstrating the arcade of Struthers (*). SRN,
superfi cial radial nerve. PIN, posterior interosseous nerve. (B) After release of the arcade.
Note the normal appearance of the PIN. RN, radial nerve. (Copyright David J. Slutsky, with
permission.)
A
B

624 • CHAPTER 53
of the elbow and the roof is a fi brous band (Osborne
ligament, arcuate ligament) that is a continuation of the
fi broaponeurotic covering of the epicondylar groove. At
the elbow, the ulnar nerve contains about 20 fascicles,
including the motor branches to the forearm muscles.
The fascicles within a nerve are not uniformly affected
by compression. Those on the periphery of a nerve sus-
tain greater injury than centrally placed fascicles. The
motor fascicles to the FCU and the intrinsics are cen-
trally located, whereas the sensory fi bers are superfi cially
located. The usual sites of compression in cubital tun-
nel syndrome are superfi cial to the nerve (Osborne liga-
ment, arcade of Struthers). The internal topography of
the ulnar nerve at the elbow explains the relative sparing
of the FCU and FDP because their motor fi bers lay deep
within the nerve. The intrinsics are often uninvolved
until the late stages of compression for similar reasons
whereas the superfi cially located sensory fi bers are more
susceptible to early compression.
The Guyon canal may be divided into three zones. In
zone 1, nerve compression leads to mixed motor and sen-
sory symptoms. In zone II, symptoms are purely sensory;
and in zone III, symptoms are purely motor and restricted
to muscles innervated by the deep ulnar motor branch.
Two sites of entrapment distal to the abductor digiti min-
imi have also been described. In these cases, the abductor
digiti minimi will be preserved while there is weakness and
wasting of the intrinsics.
Radial Nerve
The radial nerve contains contributions from C5–C8 spinal
roots and arises from the posterior cord of the brachial
plexus. The nerve runs medial to the axillary artery. At the
level of the coracobrachialis, it courses posteriorly to lie
in the spiral groove of the humerus. In the lower arm, it
pierces the lateral intermuscular septum to run between
the brachialis and brachioradialis. Opposite the head of the
radius, there are some fi brous bands from the joint’s cap-
sule and immediately distal to this, the nerve is regularly
crossed by several prominent veins, the “leash of Henry.”
It divides 2 cm distal to the elbow into a superfi cial radial
nerve (SRN) and a deep motor branch, the posterior
interosseous nerve (PIN). It gives off branches to the, exten-
sor carpi radialis longus (ECRL) and brevis (ECRB), bra-
chioradialis and anconeus before giving off the PIN branch.
The PIN continues on between the superfi cial and deep
head of the supinator muscle, to exit on the dorsal forearm.
After it emerges from the distal border of the supinator,
the PIN sends branches to the extensor digitorum com-
munis (EDC), extensor carpi ulnaris, extensor digiti quinti,
extensor pollicus longus and brevis, and the extensor indicis
proprius (EIP) in descending order, although there may be
considerable variation. The radial sensory nerve exits from
under the brachioradialis approximately 5.0 cm proximal
to the radial styloid and bifurcates into a major volar and a
major dorsal branch at a mean distance of 4.2 cm proximal
to the radial styloid. It then moves distally where it supplies
sensation to the dorsum of the thumb, the fi rst web space
and the dorsoradial aspect of the carpus, extending up to
the index and middle fi ngers.
Entrapment of the PIN at the elbow can result in two
separate clinical syndromes. Although the same nerve is
compressed, the clinical presentation may be different
and merely represents two ends of the spectrum of PIN
compression. The PIN is said to be a motor nerve, but it
also contains sensory nerve branches from which the pain
from radial tunnel compression is derived. The different
clinical presentation may refl ect the internal fascicular
topography of the radial nerve. Pain symptoms predomi-
nate with nerve compression secondary to superfi cial
structures and motor paralysis occurs from compression
from below due to lesions arising from the radiocapitellar
joint. As it travels distally through the radial tunnel, the
PIN may potentially be entrapped by fi brous bands ante-
rior to the radiocapitellar joint, the radial recurrent leash
of vessels, the fi brous edge of the ECRB, the proximal bor-
der of the supinator, ie, the arcade of Frohse or the distal
edge of the supinator muscle.
PATIENT SELECTION
Median Nerve Compression
The patient with median nerve compression will
typically complain of numbness and paresthesia along the
nerve’s distribution. Clinical symptoms of pronator syn-
drome include forearm pain as well as distal median par-
esthesia. Symptoms are typically precipitated by activity,
especially repetitive elbow fl exion/extension and forearm
pronation/supination. Nocturnal paresthesias are not com-
mon as they are with CTS. Numbness and tingling may
also involve the thenar area supplied by the palmar cuta-
neous branch, which takes off proximal to the carpal trans-
verse ligament and is not compressed in CTS.
Phalen and Durkan tests will be negative in pronator
syndrome unless CTS coexists. There may be a positive
Tinel sign over the proximal nerve as well as a fi rm and
tender pronator teres and tenderness along the median
nerve in the proximal forearm. Manual compression of
the median nerve over the pronator teres for 30 seconds
(ie, pronator compression test) may elicit paresthesia in
the median nerve distribution. Pain or paresthesia pro-
duced by resisted forearm supination in combination with
resisted elbow fl exion beyond 120 degrees suggests com-
pression at the bicipital aponeurosis. Paresthesia resulting
from resisted forearm pronation, while the elbow is slowly
extended from full fl exion, is indicative of compression
between the two heads of the pronator teres. Resisted
proximal interphalangeal (IP) joint fl exion of the middle
fi nger producing paresthesia in the radial three digits and/
or pain over the FDS arch is consistent with entrapment
under the fi brous origin of the FDS. These tests are, how-
ever, neither specifi c nor sensitive.

COMPRESSIVE NEUROPATHIES IN THE UPPER EXTREMITY • 625
Anterior interosseous nerve syndrome (AINS) must
be differentiated from a brachial plexus neuritis (Parsonage-
Turner syndrome) in which there is usually no history of
trauma. The pain symptoms may be unrelated to the motor
fi ndings, and can appear spontaneously or following a viral
illness or vaccination. By contrast, the patient with AINS
will usually have a history of trauma or repetitive injury.
Complaints will include vague, aching pain in the proxi-
mal forearm, which occurs at rest and is exacerbated by
activity. The patient can have diffi culty with writing and
pinching activities, and they may have sensory abnormali-
ties in the median nerve distribution.
AINS is characterized by loss of function of the FPL
and FDP to the index and sometimes the long fi nger and
the pronator quadratus. Sensibility is unaffected. Inability
to make an “O” sign during attempted tip pinch results
in extension of the index fi nger at the distal IP joint with
compensatory increased fl exion at the proximal IP joint.
The thumb hyperextends at the IP joint with increased
fl exion of the metacarpophalangeal joint. The pronator
quadratus can be tested by resisted pronation with the
elbow fl exed to relax the pronator teres. AINS can be
incomplete, with either weakness or absence of the FPL
or FDP of the index fi nger alone with normal pronator
quadratus function. All of the profundus tendons may be
innervated by the AIN, with subsequent weakness of all
the fi ngers. The hand intrinsic muscles may be affected if
there is a coexisting Martin-Gruber anastomosis. This is
where C8-T1 motor fi bers destined for the hand intrin-
sics travel in the median nerve. They then cross over to
the ulnar nerve, usually through connections in the AIN
(91%). If the FDS is also innervated by the AIN (30%),
patients may present with weakness in this muscle also.
One must differentiate between AINS and rupture of the
FDP or FPL, which may occur from rheumatoid arthritis,
Keinböck disease, and scaphoid nonunion. The integrity of
these tendons can be assessed by observing the tenodesis
effect of the FPL and the index FDP. This causes passive
thumb IP and index distal interphalangeal fl exion with
passive wrist extension.
Initially symptoms of CTS occur at night due to a com-
bination of wrist fl exion during sleep and fl uid shifts that
occur with the horizontal position, which increases the car-
pal canal pressure. With early compression the symptoms
are intermittent, and the edema is reversible. As the symp-
toms progress, they become more frequent during the day
and are precipitated by gripping and pinching activities as
well as those tasks requiring repetitive wrist fl exion. CTS
represents a constellation of signs and symptoms in which
no one test absolutely confi rms its diagnosis. A positive
Tinel sign may be present over the median nerve at the
wrist, and produces paresthesia in the thumb and radial
2.5 digits. The Phalen test consists of subjective paresthesia
in the median nerve distribution with passive wrist fl ex-
ion for 1 minute. This is best performed with the elbows
extended because simultaneous wrist and elbow fl exion
may reproduce ulnar nerve symptoms as well. Direct
compression of the nerve or the Durkan test is thought to
be more sensitive.
Ulnar Nerve Compression
The patient with ulnar nerve entrapment presents with
complaints of numbness and/or tingling in the small and/
or ring fi nger. Symptoms can range from mild numbness
in the ring and little fi ngers to severe pain on the medial
aspect of the elbow with dysesthesia radiating distally into
the hand. In chronic cases, patients may complain of a loss
of dexterity with fi ne manipulation tasks. Symptoms are
provoked by repetitive or sustained elbow fl exion activi-
ties. The ulnar nerve is palpated for enlargement or sub-
luxation during elbow fl exion. There may be a positive
Tinel sign at the epicondylar groove or over the proximal
FCU. An elbow fl exion test is performed and consists of
placing the elbow in full fl exion with a hyperextended
wrist, while manual pressure is applied to the nerve for
1 minute. The test is considered positive when paresthe-
sia and/or numbness occur in the ulnar nerve distribution
of the hand. False-positive results occur in approximately
10% of patients. There may be a sensory defi cit involv-
ing all or part of the ulnar nerve distribution, including
the dorsoulnar carpus. When intrinsic muscle weakness
is severe, there is often clawing of the ring and little fi n-
gers. One may see a positive Froment sign (fl exion of the
IP joint of the thumb with side pinch), a positive Jeanne
sign (hyperextension of the metacarpophalangeal joint of
the thumb), and paradoxical abduction of the small fi n-
ger due to a paralyzed third palmar interosseous (posi-
tive Wartenberg sign). Extrinsic weakness may involve the
FDP to the little fi nger and ring fi nger. Weakness of the
FCU rarely occurs.
Patients with distal ulnar nerve entrapment may pres-
ent with complaints of numbness and tingling of the
small and/or ring fi nger sparing the dorsoulnar aspect
of the hand. The patient may give a history of repetitive
trauma to the hypothenar eminence as seen with auto-
mobile mechanics, martial artists, and Kodo drummers.
A history of Raynaud symptoms should alert one to the
possibility of ulnar artery thrombosis. There are no char-
acteristic fi ndings of ulnar tunnel entrapment per se. A
Tinel sign may be present at the wrist but not the elbow
unless there is an associated cubital tunnel entrapment.
Intrinsic atrophy may also occur in chronic compression,
but the FCU and the FDP are not affected. There should
be a negative Tinel sign at the elbow and a negative elbow
fl exion test. If there is an associated ulnar artery aneurysm
there may be a palpable thrill and an audible bruit. With
ulnar artery thrombosis, the Allen test will be positive for
ulnar artery occlusion. With an associated fracture of the
hook of the hamate, there will be localized tenderness
in the palm, 1 cm radial and 1 cm distal to the pisiform.
Ancillary testing such as ultrasound, CT, angiography, and
MRI may be employed to aid in the diagnosis of these
associated entities.

626 • CHAPTER 53
Radial Nerve Compression
In the arm region, radial nerve palsy often occurs in asso-
ciation with some form of unconsciousness. In “Saturday
night” palsy, an obtunded patient sits with his arm over a
chairback or rests his head on the lateral surface of his arm.
Alternatively, the radial nerve can be compressed in the
groove between the brachialis and forearm muscles when
one person rests her head on the middle third of the arm
of another (“Honeymooner’s” palsy). The patient will typi-
cally present with a wrist drop and an inability to extend
the fi ngers, thumb, or wrist. In addition, the brachioradia-
lis will be affected along with variable involvement of the
triceps. They will also have diminished sensation over the
dorsum of the fi rst web space.
The presenting complaint in radial tunnel syndrome
(RTS) is proximal forearm pain often coexisting with
lateral epicondylitis, with neither sensory nor motor loss.
The patient often gives a history of performing repetitive
pronation/supination activities, such as using a screwdriver.
The symptoms of RTS often coexist and overlap those of
lateral epicondylitis. A number of provocative tests have
been described, including resisted extension of the middle
fi nger, which tenses the ECRB and entraps the nerve, ten-
derness over the supinator muscle and pain with resisted
supination. None are pathognomonic for this condition
however. A diagnostic local anesthetic block of the PIN,
which produces a temporary wrist drop is useful if the pain
is completely relieved.
In PIN syndrome, the presenting symptoms are weak-
ness and/or paralysis of the extensor muscles, which result
in a wrist or fi nger drop. There may be a history of a fall
onto an extended and pronated arm, although many cases
are spontaneous, especially if due to an underlying lipoma,
ganglion, or rheumatoid nodule arising from the radio-
capitellar joint. The patient will demonstrate variable
weakness or paralysis of the extensor pollicus longus, EIP,
EDC, and extensor carpi ulnaris. Motor function of the
ECRB/L should be preserved because they are innervated
before the PIN dives between the two heads of the supi-
nator muscle. The patient will hence extend their wrist in
radial deviation.
The SRN can be injured in the distal forearm or at
the wrist by tight bracelets or watchbands, handcuffs,
radius fractures, lacerations, venous cutdown, and blunt
trauma. The SRN may also be entrapped as it exits the
fascia between the tendons of the brachioradialis and
ECRB. In patients with entrapment of the SRN, the pre-
sentation may include a history of compressive or crush-
ing forearm injuries, work activities requiring frequent
pronation and wrist hyperextension, and associated ill-
nesses, such as diabetes. Patients may complain of altered
sensibility over the dorsoradial aspect of the hand and
dorsoradial cutaneous pain with ulnar fl exion of the wrist
or with gripping and pinching. The physical examination
may demonstrate alteration in touch perception, moving
two-point discrimination .15 mm, static two-point dis-
crimination (s2PD) more than 5 mm difference versus
the contralateral fi rst web space, a positive Tinel sign over
the course of the nerve, and aggravation of the patient’s
symptoms with forced forearm pronation and wrist ulnar
fl exion.
PATIENT PREPARATION
Electrodiagnostic Studies
Ancillary tests include nerve conduction studies (NCSs)
and quantitative sensory testing. These cannot replace a
detailed history and thorough examination of the upper
limb, but they can provide a means for staging the degree
of neuropathy and for ruling out more generalized dis-
orders that may masquerade as a focal neuropathy. A
recording electrode will detect activity in the largest
myelinated fi bers fi rst, since these fi bers conduct at the
fastest rates and have a lower depolarization threshold
than the small unmyelinated nerves. Large fi bers are also
more vulnerable to compression and ischemia than are
small fi bers.
Latency and conduction velocity depend on the time
that transpires from stimulation of the nerve to the fi rst
recording. If only a fraction of the large thickly myeli-
nated fi bers remain and transmit impulses, the recorded
latency and conduction velocity remains normal because
the recording electrode mostly detects the fastest fi bers.
The electrical conduction in smaller, thinly myelinated
or nonmyelinated nerves is much slower and hence not
usually detected in a routine NCS. Large myelinated and
small unmyelinated fi bers can be affected differently. The
large myelinated nerves undergo segmental demyelination,
and the small unmyelinated nerves undergo degeneration
and regeneration. An NCS only tests the faster conducting
fi bers. This explains the paradox of the patient who has
established carpal tunnel syndrome but shows normal on
electrodiagnostic studies. It is the worst fascicles that pro-
duce symptoms, but it is the best fascicles that account for
the normal nerve conduction studies.
The presence of fewer nerve fi bers reduces the size of
the electrical charge, leading to smaller amplitudes. When
there is sensory or motor loss, there is usually degenera-
tion of nerve fi bers. Despite the restoration of neural blood
fl ow following nerve decompression, remyelination of the
axon is often incomplete, which accounts for persistently
abnormal nerve conduction, even though the patient may
be without symptoms.
Quantitative sensory testing is reportedly more sensitive
than the NCS, as only 25% of the large myelinated nerve
fi bers need to be conducting normally in order to yield a
normal nerve conduction test. With nerve degeneration it
is more diffi cult to distinguish two points from one point.
Static and moving two-point discrimination typically test
the innervation density. Threshold tests would include
vibrometry and Semmes-Weinstein monofi lament testing.
Vibrometry is relatively insensitive to early changes and is
not commonly used. Semmes-Weinstein testing involves
placing nylon fi laments of varying thickness on the skin

COMPRESSIVE NEUROPATHIES IN THE UPPER EXTREMITY • 627
until the fi lament is seen to defl ect. The test is repeated
with varying diameter fi laments until the threshold is
determined. An abnormal Semmes-Weinstein test is con-
sistent with nerve demyelination.
Median Nerve Testing
NCSs are rarely diagnostic for pronator syndrome. There
may be prolongation of the distal median sensory laten-
cies as well as reduced amplitude of the compound motor
action potential (CMAP) to the abductor pollicis brevis.
There may be slowing of forearm conduction but this can
be misleading since reduced forearm velocity is seen up to
20% to 30% of the time when there is a markedly delayed
distal median motor latency due to severe CTS. Needle
stimulation of the median nerve in 1 cm increments while
recording from the abductor pollicis brevis may identify
an area of focal conduction block near the pronator teres
muscle. Nerve conduction studies during provocative
maneuvers such as elbow fl exion, forearm pronation, and
middle fi nger fl exion against resistance do not increase the
yield. The electromyography (EMG), however, may be of
some value since membrane instability may be seen in the
median-innervated muscles, including the pronator teres,
FCR, and FDS.
Shoulder girdle and upper limb EMG in AINS should
be performed to rule out a brachial plexitis. In this case,
there will be membrane instability in the proximal
limb muscles. The most appropriate technique involves
recording the CMAP from the pronator quadratus. Side-
to-side comparative latencies are helpful in establishing
the diagnosis. EMG testing of the pronator quadratus
and FPL muscles should demonstrate signs of mem-
brane instability. Quantitative sensory testing should be
entirely normal since the condition only affects a motor
branch. Any abnormalities are due to nonrelated causes
conditions.
The nerve conduction study can yield useful informa-
tion in carpal tunnel syndrome, but the severity of the
preoperative nerve conduction defi cit does not provide
signifi cant data for prediction of the fi nal outcome or
return to work after carpal tunnel release (CTR). There
are some caveats for NCSs in CTS. First, sensory abnor-
malities usually occur before motor abnormalities. In
other words, the distal sensory latencies often slow before
the distal motor latency. This is not surprising since 94%
of the axons in the median nerve at the wrist level are
sensory. The sensory nerve axons are larger than the
motor axons and hence more susceptible to compression.
If the distal motor latency is abnormal in the presence
of normal sensory nerve action potentials (SNAPs), extra
care must be taken to rule out anterior horn cell disease
or a 8 radiculopathy, although isolated recurrent motor
branch compression has been reported. Second, the nerve
conduction studies may not return to normal following
decompression due to retrograde fi ber degeneration or
incomplete remyelination, even in the presence of a full
clinical recovery.
Ulnar Nerve Testing
On quantitative sensory testing, s2PD testing remains nor-
mal in mild cases. With more severe and/or longer standing
median nerve compression, the s2PD becomes abnormal
(ie, .5 mm) in variable combinations of the thumb, index,
middle, and radial ring fi nger. Loss of protective sensation
occurs when the s2PD is .15 mm, and .25 mm corre-
lates with complete anesthesia. Two-point discrimination
is relatively insensitive in picking up changes as compared
with testing using the pressure-specifi ed sensory device
(PSSD) devised by Lee Dellon. In CTS testing of the index
fi nger, pulp may initially show an abnormal s2PD pressure
threshold. With progression, the surgeon sees a widen-
ing of the s2PD distance, followed by an abnormal s1PD
threshold. A prospective side-by-side comparison of NCS
and PSSD testing was undertaken in 60 patients (86 tests)
with clinical signs and symptoms of CTS (D. J. Slutsky,
unpublished data). Eleven of these patients then under-
went a CTR and were tested again at 6 months. Clinical
improvement was gauged by relief of symptoms, absent
provocative tests and at least a 1.04 improvement in the
Brigham CTS questionnaire. Both the NCS and PSSD
were roughly comparable in terms of sensitivity and speci-
fi city. When combined, however, 80/86 cases of CTS were
detected, including 14 patients who had symptoms of CTS
but negative clinical signs.
Ulnar motor studies are more popular than ulnar sen-
sory studies. The distal motor latency is determined by
recording from an electrode placed over the midpoint of
the abductor digiti minimi while stimulating the ulnar
nerve 8 cm proximally (S1). Normal values include a distal
motor latency less than or equal to 3.6 ms and amplitude
greater than 4.0 mV. Alternatively, the latencies can be
measured from the fi rst dorsal interosseous (FDI), which
then assesses conduction through the deep motor branch
of the ulnar nerve. The FDI to abductor digiti minimi
latency should not exceed 2.0 ms. The ulnar nerve is then
stimulated 4 cm distal to the medial epicondyle (S2). By
subtracting the latency for S1 from S2 and measuring the
intervening distance, the forearm conduction velocity is
obtained. Ulnar nerve conduction across the cubital tun-
nel is calculated by stimulating the nerve at S3, which is
12 cm proximal to S2, and subtracting the latencies. Most
labs measure conduction with the elbow fl exed between
90 and 135 degrees. Normal forearm NCV is greater than
48 m/s. Across the cubital tunnel the NCV should be
greater than 45 m/s. More than 10 m/s of slowing between
the above and below elbow NCV is abnormal. Amplitude
drops of greater than 20% are a more sensitive indicator of
conduction block or axonal loss.
Ring electrodes are placed on the small fi nger and the
ulnar nerve is stimulated 14 cm proximally. Recordings
are also taken from the ring fi nger after stimulation of both
the ulnar and median nerves. This allows for comparison
of the ulnar to the median SNAPs. Normal peak sensory
latencies are less than or equal to 3.5 ms and less than
0.5 ms median-ulnar difference. Mixed palmar orthodromic

628 • CHAPTER 53
studies can be elicited by stimulating the ulnar nerve in the
fourth web space and recording over the ulnar nerve at
the wrist 8 cm proximally. This measures the sensory nerve
conduction through Guyon canal. Normal values are less
than 2.2 ms.
Combining ulnar motor and sensory techniques adds
useful information in complex cases, where clinical exami-
nation fails to localize the lesion. Conduction to the dorsal
cutaneous branch of the ulnar nerve can be measured. This
test is relatively insensitive for detecting proximal ulnar
nerve compression, since it is abnormal in only 55% of
patients with cubital tunnel syndrome. Electromyography
demonstrates axonal degeneration in muscles. Because
these changes are seen in chronic neuropathies, EMG is
not as useful as conduction times for the diagnosis of early
nerve compression. When muscle abnormalities are noted,
they are usually initially seen in the intrinsic muscles, gen-
erally the fi rst dorsal interosseous, followed in frequency
by the muscles in the hypothenar eminence. On quantita-
tive sensory testing, PSSD testing shows an abnormal s2PD
in the ring and small fi nger initially, followed by increased
s1PD. Abnormal s2PD may also be seen over the ulnar
dorsum of the hand.
The usual nerve conduction studies are inadequate at
assessing distal ulnar nerve entrapment. Short segment
incremental studies is a sensitive and specifi c way to assess
the deep motor branch since focal conduction abnormali-
ties also tend to be normalized over the distance between
the abductor digiti minimi and the FDI. The ulnar nerve
is stimulated in 1 cm increments from 3 to 4 cm proximal
and distal to the wrist crease. Abnormal values include a
greater than 0.5 ms jump or a greater than 120% drop in
amplitude. When this is combined with FDI conduction
and interosseous-latency differences, the diagnostic yield
increases. On quantitative sensory testing, the s2PD to
the small fi nger is the fi rst to go, followed by an abnormal
s1PD. The dorsoulnar carpus should remain normal unless
there is an associated C8-T1 radiculopathy.
Radial Nerve Testing
With palsy of the radial nerve, the NCS typically demon-
strates the absence of the superfi cial radial SNAP. Motor
recordings are more diffi cult since no muscle is suffi ciently
isolated from other radially innervated muscles. A sur-
face electrode over the EIP results in a volume conducted
response from the adjacent radial innervated muscles,
which makes side-to-side amplitude comparisons diffi cult.
Radial nerve recordings using needle electrodes in the EIP
are more common as a result, which makes it diffi cult to
approximate the degree of axonal loss by assessing the
amplitudes. The EMG, however, is quite useful and per-
mits a relatively accurate localization of the lesion. In a spi-
ral groove lesion, for example, all three heads of the triceps
should be normal, with denervation of the brachioradialis
and all muscles distal to it. With quantitative sensory test-
ing, the patients will have an abnormal s2PD and possibly
s1PD over the dorsum of the fi rst web.
In both radial tunnel and PIN compression, sensory
testing over the dorsum of the fi rst web space should be
normal unless there is a superimposed C6 neuropathy.
Some authors have postulated that RTS refl ects a dynamic
entrapment of the PIN. If the ECRB develops a fi brous
edge, the PIN can be entrapped by a scissoring action
between this edge and the arcade of Frohse during repeti-
tive forearm supination and pronation. This can lead to
intermittent PIN compression. Differential latency testing
is based on this premise. Across elbow radial motor nerve
conduction is performed with the elbow extended and the
forearm positioned in neutral, pronation, and supination
for 30 seconds. The testing is then repeated. An abnormal
latency difference of greater than 0.30 ms is indicative of
radial tunnel entrapment.
Compression of the PIN does not affect the superfi cial
radial SNAP, which should be normal. The CMAP of PIN
innervated muscles may show a drop of conduction veloc-
ity or amplitude, but this is diffi cult to assess with surface
electrodes. Needle EMG is the best technique for local-
ization, especially with partial lesions. In acute denerva-
tion decreased recruitment, increased insertional activity
and fi brillation potentials plus/minus positive sharp waves
are present. In chronic lesions seen after 3 to 6 months,
decreased recruitment may still be seen along with giant
motor unit potentials and polyphasia due to peripheral
axonal ingrowth.
On quantitative sensory testing, patients with SRN
compression will have an abnormal s2PD and possibly
1PS over the dorsum of the fi rst web space. With elec-
trodiagnostic studies, the distal radial sensory latency may
be normal even in the presence of abnormal forearm con-
duction. This commonly occurs with nerve entrapment
due to segmental conduction velocity slowing. In more
advanced cases, slowing or a complete block of the dis-
tal SRN occurs. If the response is absent, it is diffi cult to
localize the lesion.
TECHNIQUE
Pronator Syndrome
The hallmark of treatment for pronator syndrome consists
of activity modifi cation and NSAIDs. Steroid injections are
of no benefi t. Immobilization in an above elbow splint with
the elbow fl exed 90 degrees with slight forearm pronation
and wrist fl exion for 4 to 6 weeks may relieve pressure and
traction on the median nerve.
Although the majority of patients will respond to
nonoperative therapy, failure to improve is an indication
for surgical release. The procedure is performed under
tourniquet control. An anteromedial incision is made
crossing the antecubital fossa, starting 5 cm above the
elbow fl exion crease. The medial antebrachial cutane-
ous nerve is isolated as it runs with the basilic vein. The
median nerve is identifi ed proximal to the elbow, next to
the brachial artery, and it is traced distally, resecting the
ligament of Struthers if present. The nerve is followed

COMPRESSIVE NEUROPATHIES IN THE UPPER EXTREMITY • 629
through the two heads of the pronator teres where
branches from the anterior bundle (FCR, pronator teres
fascicles) are given off. Both the superfi cial head of the
pronator teres and the FDS can be divided and tagged for
later repair if better exposure is needed. The posterior
(AIN branch) and the middle (intrinsic, sensory) bundles
pass deep to the superfi cialis arch, which is also incised.
Epineurotomy or internal neurolysis is of no benefi t.
Subcutaneous transposition of the median nerve is also
not recommended. Postoperatively, the arm is placed in
an above elbow splint for comfort with the elbow fl exed
90 degrees, the forearm in midpronation and the wrist
in slight fl exion. Gentle elbow range-of-motion exercises
are begun after the fi rst week, unless it is necessary to
protect the reattachment of the pronator teres and/or
FDS insertions. Resistive activities are avoided until 6 to
8 weeks postoperatively.
If there is no improvement either clinically or by EMG
studies 4 to 6 months after onset, surgical exploration is
indicated. Even though return of function has been reported
up to 18 months after onset of symptoms, expectant treat-
ment is less predictable than surgical intervention. The
surgical approach for AIN palsy is essentially the same as
for pronator syndrome. A microscopic interfascicular neu-
rolysis of the AIN up to the elbow should be considered in
cases where there is no obvious compression site because
hourglass-like fascicular constrictions that are not discern-
ible through the intact epineurium have been reported.
The arm is placed in a bulky, above-elbow plaster splint
that maintains the elbow at 90 degrees of fl exion, the fore-
arm in 45 degrees of pronation, and the wrist in slight fl ex-
ion for comfort.
Nonoperative therapy for CTS includes splinting the
wrist in a neutral position, steroid injections, and manage-
ment of any underlying systemic diseases. Steroid injec-
tion offers transient relief to 80% of patients, but only
20% will be symptom-free 12 months later. Those most
likely to benefi t from conservative management have had
symptoms for less than 1 year, only intermittent numb-
ness, normal two-point discrimination, less than 1 to 2 ms
prolongation of distal motor and sensory latencies, and no
motor fi ndings. Forty percent of this group will remain
symptom free for longer than 12 months.
A failure of nonoperative treatment is an indication for
surgical release. The procedure is performed under tour-
niquet control. A 3- to 5-cm incision is made in the palm
parallel to the thenar crease and inline with the ring fi nger
axis in order to protect the palmar cutaneous branch of
the median and ulnar nerves ( Figure 53-3A – B ). Tenotomy
scissors are used to spread down to the palmar aponeu-
rosis. This is divided exposing the transverse carpal liga-
ment. The TCL is divided from distal to proximal. This
procedure can also be performed through a mini-incision
technique. A hemostat may be used to protect the median
nerve. The skin is retracted and the deep fl exor retinacu-
lum is divided under direct vision for an additional 2 cm.
The nerve and tendons are retracted to the radial side
and the fl oor of the canal is inspected for any masses. The
recurrent motor branch is inspected and decompressed
separately, if necessary. Postoperatively, fi nger motion
may begin immediately, which also aids in median nerve
excursion. A below elbow splint is applied for comfort for
the fi rst week, followed by desensitization and progressive
strengthening.
In advanced cases of median nerve compression,
inter nal neurolysis and epineurotomy have both been
described. Their effi cacy has not been supported by clini-
cal studies and they are no longer advocated. Small fi nger
numbness due to coexistent Guyon canal compression
often improves after CTR alone, since MRI studies have
demonstrated an increase in the volume of Guyon canal
after a CTR. Routine tenosynovectomy does not pro-
vide better results than CTR alone and is mostly recom-
mended with associated proliferative tenosynovitis from
some other cause, such as rheumatoid arthritis or granu-
lomatous infection.
B
FIGURE 53-3. (A) Anteromedial approach to the median nerve. Note the fi brous
border of the sublimus muscle. PT, pronator teres; AIN, anterior interosseous nerve;
FDS, fl exor digitorum sublimus. (B) Following release of the sublimus arch. (Copyright
David J. Slutsky, with permission.)
A

630 • CHAPTER 53
Ulnar Nerve
Most acute or subacute cases of distal ulnar nerve entrap-
ment resolve by activity modifi cation with avoidance of
activities that require repetitive elbow fl exion and avoid-
ing external pressure from leaning on their medial elbow or
forearm. Alterations can sometimes be made in the work-
place, such as positioning a computer keyboard so that
the operator’s elbows are not acutely fl exed. When symp-
toms are severe and have persisted for weeks, temporarily
immobilizing the elbow in approximately 35 degrees of
fl exion and the wrist in neutral may provide relief. Patients
are instructed to wear the splint day and night for 3 to
4 weeks. NSAIDs can be helpful but corticosteroid injec-
tions around the nerve are ineffective.
In patients with recurring symptoms, surgery is often
necessary. In the absence of muscle weakness, the timing
for surgery is totally dependent on the severity of symp-
toms. Muscle wasting and weakness are an indication for
surgery. Surgery can be divided into two groups of proce-
dures: decompression without transposition of the ulnar
nerve and decompression with transposition of the nerve.
The procedures are performed under axillary block or gen-
eral anesthesia using a tourniquet.
To perform a subcutaneous anterior transposition, a
5-cm posteromedial incision is made over the medial epi-
condyle. Branches of the medial antebrachial cutaneous
nerve are identifi ed and protected. The deep fascia over-
lying the proximal ulnar nerve is divided as well as any
associated ligament of Struthers. The fascia over the nerve
is released sequentially; fi rst in the upper arm, followed
by the fi broaponeurotic covering of the epicondylar groove,
then Osborne ligament at the cubital tunnel, and fi nally,
the fascia where the nerve passes between the two heads
of the FCU. A 1-cm segment of the medial intermuscular
septum is resected where it attaches to the epicondyle
to prevent a secondary site of compression, taking care
to prevent injury to fragile veins medial to the septum.
Articular branches to the elbow are divided but motor
branches to the FCU should be preserved. A vessel loop is
placed around the nerve, which is then gently transposed
anterior to the medial epicondyle along with the superior
ulnar collateral vessels ( Figure 53-4 ). A 1-cm-wide medi-
ally based fl ap of fascia from the common fl exor origin can
be turned down and sutured to the proximal skin edge to
prevent posterior subluxation of the nerve. The patient
uses a sling for comfort postoperatively and is started on
progressive elbow extension as tolerated.
To perform submuscular transposition, a slightly larger
incision is made and the nerve is decompressed in a simi-
lar fashion. A z-plasty lengthening of the common fl exor
origin is preserved and the nerve is transposed deep to the
muscle. Care must be taken to divide the fi brous attach-
ment of the FDS to the humeral epicondyle to prevent sec-
ondary impingement while avoiding injury to the medial
collateral ligament of the elbow. The ulnar nerve is now
positioned onto the bed of the brachialis muscle and it is
important to ensure that its path from the proximal end
of the operative fi eld to the distal end is relatively straight.
The fl exor-pronator mass is then repaired with 2-0 nonab-
sorbable sutures. Postoperatively the elbow is immobilized
at 90 degrees for 4 weeks, allowing elbow fl exion but no
extension. The elbow is then gradually extended over the
ensuring 2 to 4 weeks.
The mainstay of treatment for distal ulnar nerve
palsy is activity modifi cation. Bicyclists should avoid rid-
ing in the crouch position with their hands low on the
handlebars, because this is a recognized precipitant of
symptoms, and change their hand position frequently.
Automobile mechanics, martial artists, and Kodo drum-
mers should avoid repetitive percussion on the ulnar bor-
der of their palm. Wrist splinting and cortisone injections
have no role in this condition. The presence of a mass-
occupying lesion mandates surgical treatment, as does a
failure to respond to conservative measures. Surgically,
the ulnar nerve is identifi ed proximal to the distal wrist
crease between the FCU and the fl exor tendons through
a curving incision which crosses the wrist obliquely, and
bisects the interval between the pisiform and the hook
of the hamate. The ulnar nerve is followed distally as
the volar carpal ligament is released. The fi brous arch of
the hypothenar muscles is incised and the fl oor of the
canal is explored for masses, fi brous bands, or anomalous
muscles. With entrapment in the palm, the deep motor
branch is followed distally as it traverses the palm lying
on the interosseous fascia, deep to the fl exor tendons and
superfi cial palmar arch. The dissection is completed as
the motor branch ends in the muscle belly of the adduc-
tor pollicus (Figure 53-5A–C).
Radial Nerve
For the majority of patients with radial nerve palsy,
nonoperative treatment is the mainstay. A nonadvanc-
ing Tinel sign combined with failure to improve within
6 months are indications for exploration. With severe
compression, surgical treatment may be necessary and

FIGURE 53-4. Mini-incision approach to a
subcutaneous anterior transposition of the ulnar nerve
(vessel loop). (Copyright David J. Slutsky, with permission.)

COMPRESSIVE NEUROPATHIES IN THE UPPER EXTREMITY • 631
FIGURE 53-5. (A) Dorsal preoperative photograph of attempted index fi nger abduction. Note the marked wasting of the
fi rst, second and third dorsal interossei. (B) Intraoperative view following an ulnar nerve decompression in Guyon canal as it
splits into a superfi cial sensory branch ( white asterisk ) and deep motor branch (*) which passes under the hypothenar arch.
(C) Six months after operation. Note the normal bulk of the dorsal interossei and the active index fi nger abduction. (Copyright
David J. Slutsky, with permission.)
A
B
C