The Unfavorable Result in Plastic Surgery_ Avoidance and Treatment (2018, Thieme)

1266
Revascularization and replantation are the reconstructions of
choice for debilitating hand injuries.1 Alternatively, when the
amputated and devascularized part cannot be revascularized
or replanted or replantation has failed, microsurgical toe-
to-hand transfer could restore the lost function and form.2
The philosophy, surgical techniques, anticipated out­
comes, and necessary refinements for any of these core re­
constructive procedures have been well investigated and
well established in the literature since the mid-1990s.3 The
ultimate goal for the surgeon performing upper extremity
Replantation of the Hand and
Toe-to-Hand Microsurgical
Transplantation
Nidal F. AL Deek, Yu-Te Lin, and Fu Chan Wei
Summary Box
Unfavorable Results and Complications
Associated with Replantation
General Replantation and Revascularization
•• Nonunion and malunion
•• Restricted tendon function
•• Poor sensory recovery and cold intolerance
•• Arterial insufficiency
•• Venous insufficiency
•• Replant loss
Unfavorable Results and Complications Associated
with Specific Types of Replantations
•• Distal replantation
○
○Replant loss
•• Ring avulsion injuries
○
○Replant loss
○
○Skin necrosis
•• Thumb replantation
○
○Poor sensation
○
○Short thumb
○
○Malpositioned thumb
○
○Replant loss
•• Transmetacarpal replantation
○
○Weak or absent intrinsic function
○
○Weak grip
○
○Poor sensory recovery
○
○Tendon adhesion
○
○Joint contracture
○
○Intrinsic tightness
○
○Bone nonunion
•• Multiple-digit replantation
○
○Nonviable thumb
○
○Inadequate web space
○
○Two viable and mobile adjacent fingers required
○
○Stable wrist
•• Major proximal replantation
○
○Sepsis
○
○Poor functioning limb
○
○Infection or reperfusion syndrome causing death
CHAPTER
65

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Chapter 65 Replantation of the Hand and Toe-to-Hand Microsurgical Transplantation
Fig. 65.1 (a,b) Multilevel amputation with severe damage. (c,d) Although replantation was successful, the hand has excessively poor func­
tion. (e) Osteosynthesis.
c
d
e
a
b
reconstruction using one of these techniques should be a fa­
vorable outcome and good patient and surgeon satisfaction
rather than replant or toe survival alone.4
To fulfill this vision and maximize the functional and
aesthetic rewards after replantation and toe-to-hand mi­
crosurgical transfer, and based on vast experience with re­
plantation and toe-to-hand microsurgical transplants in our
center, we try to identify those untoward results and pro­
pose pearls and tips on how to circumvent and correct un­
favorable outcomes in this rewarding yet demanding field of
reconstructive microsurgery.
Replantation
Avoiding Unfavorable
Results and Complications in
Replantation
Revascularization and replantation can now achieve a 70 to
90% success rate.5 This percentage is significantly less than
that of free flap transfer,6 reflecting unfavorable circum­
stances for the surgery and also expanding the indications
for more challenging indications, such as single finger am­
putation distal to the insertion of sublimis tendon, finger­
tip amputation, and ring avulsion amputations.4,5
The surgery is complex with narrow margins for error.
Thorough preparation and meticulous execution are ex­
tremely important to avoid any untoward outcomes. Spe­
cial considerations related to the level of amputation and
replantation and the mechanism of injury should be taken
into account before surgery.
Planning, Decision-Making, and
Preparation
The unfavorable results that result from poor planning,
decision-making, and preparation will affect replant sur­
vival and functional outcome, the patient’s psychology and
function, and treatment cost.7 Replantation should not be
attempted in every occasion the surgeon deals with the
amputation. In some cases, as described in this paragraph,
complications may arise and the patient will endure pro­
longed suffering. Therefore knowing when not to replant is
vital for the avoidance of unfavorable results.
When Not to Replant
A common pitfall is replanting a nonreplantable part that
will eventually fail or result in a nonfunctional thumb at
best (Fig. 65.1); therefore, replantation should not be at­
tempted when all tissues are severely damaged or avulsed,
multiple segmental injuries are noted (Fig. 65.2), extreme
contamination is evident, or a ribbon sign or redline sign
are apparent. Similarly, prolonged ischemia is a contrain­
dication for replantation of proximal major amputations.4–8

SECTION VIII THE HAND AND UPPER EXTREMITY
1268
because of the long damaged segment in avulsion injuries
that often needs to be grafted.4,7–10 Bone shortening is usu­
ally performed at the diaphyseal ends away from the joints
and should aid in comminuted fracture reduction, convert­
ing a complex fracture type into a simpler one that is easy
to reduce and fix.32
Determining Alternatives
When replantation is not possible, spare part surgery should
be.11 Amputation and revision that takes into account sec­
ondary toe-to-hand transfer after adequate soft tissue cover­
age may be a good alternative12 (Fig. 65.3).
Proper Preparation
Once the part is determined to be replantable, good prepa­
ration is essential. Inadequate preparation leads to infec­
tion, nonunion, unnecessary use of vein grafts, and replant
loss. Common pitfalls in preparation include inadequate
débridement of all dirty and contaminated, nonviable,
and nonfunctionally valuable tissues and inadequate bone
shortening resulting in repair under tension or poor frac­
ture reduction. Débridement has to be thorough and radi­
cal. As for bone shortening, it is considered adequate when
skin, tendons, and veins can be repaired directly without a
graft. Arteries and nerves need to be considered separately
Fig 65.2 Severe multisegmental injury. Replantation is not advised in such situations.
Fig. 65.3 (a) Multisegmental injury; replantation should be avoided. (b) A pedicled groin flap was used for coverage and preparation of a
secondary toe transfer. (c,d) Reasonable hand function after great toe transfer, at 22-year follow-up.
a
b
c
d

1269
Chapter 65 Replantation of the Hand and Toe-to-Hand Microsurgical Transplantation
digital pulse pressure is greater than 80% of the normal side
and when the replant achieves S3+ or more.15
Based on that, meticulous nerve repair by an experi­
enced surgeon is recommended. Furthermore, in an exten­
sive crush injury, delayed repair or secondary grafting could
be a sound option.15 Although the number of repaired arter­
ies will not affect the quality of sensory recovery, the more
arteries repaired, the faster the recovery. Moreover, selec­
tion of a proximal arterial stump may provide higher digital
pressure, resulting in less severe cold intolerance. Finally,
sensory reeducation is expected to improve the speed and
quality of recovery.15
Arterial Insufficiency
Vessel selection and preparation can minimize complica­
tions. Therefore the surgeon should select the larger artery;
the ulnar digital artery for the thumb and radial two fin­
gers and the radial digital artery for the ulnar two fingers. A
healthy lumen is necessary in proximal and distal arteries,
and the proximal artery must have sustained pulsatile flow.
Although replants can survive on one artery, a two-artery
repair will allow faster sensory recovery and reduce the in­
cidence of cold intolerance. Vein or arterial grafts should be
used liberally.7,15
Venous Insufficiency
A few key steps can ensure an uneventful venous repair.
Venous repair is usually done before the artery to mini­
mize congestion of the digit. Dorsal veins are preferred, but
sometimes volar veins can be used. Use of more than two
veins is preferred and is associated with improved survival
of the replant. Tight skin closure should be avoided. Veins,
unlike arteries, have a fragile wall; therefore segmental in­
jury is rare and grafts are seldom indicated.7–10,16
Replant Loss
Failure is the most feared complication. The failure rate
can be decreased by optimization of the surgical plan and
performance and dedicated postoperative monitoring to
ensure early detection of vascular compromise and timely
intervention for improved replant survival. The salvage rate
depends on the timing of take back; a 66 to 88% success rate
can be achieved in early take backs.17
Replant monitoring can be achieved by clinical inspec­
tion combined with digital thermometry to increase the
sensitivity and specificity of detecting failure of perfusion.
Alternatively, laser Doppler with higher sensitivity and spec­
ificity for digital perfusion may be used for monitoring.18
If the replant fails despite salvage effort, amputation is
performed, and the wound is managed depending on the
level and extent of amputation by bone shortening and di­
rect coverage, reserving the potential for future toe transfer
or a distant pedicled flap in more extensive, proximal am­
putations.
Managing Unfavorable
Results and Complications in
Replantation
Satisfactory function is as important as viability for replan­
tation. Erroneous surgery will inevitably result in subop­
timal function and increased secondary procedures that
­offer little gain. Surgery, therefore, should be carried out
with utmost perfection from the beginning.
Nonunion and Malunion
To avoid nonunion and malunion, the surgeon should aim
for fixation that is rigid, simple, and quick; reduces pain;
and allows early mobilization.13 Management is more chal­
lenging and may necessitate corrective osteotomy, with
care not to injure repaired vessels and to minimize poten­
tial tendon adhesion.
Restricted Tendon Function
Despite optimal tendon repair, tendon adhesion is not
uncommon after the finger, transmetacarpal, and carpal
­replantations indicated in up to 13% of the cases. Other fac­
tors that contribute to limited range of motion at the time
of tenolysis could be tendon rupture (as high as 20%), joint
contracture necessitating capsulotomy (up to 15%) or re­
placement (5%), and web space contracture.14
Surgery is indicated at an average of 8 to 10 months after
replantation.4 Tenolysis, despite the difficulty of performing
it, is a worthy procedure that yields significantly better total
active motion (TAM) and passive active motion (PAM) com­
pared with pretenolysis levels.
Improvement, however, is expected to be less in zone II,
in crush and avulsion injury, and in more-than-two-finger
amputation.14 Tendon rupture remains the main compli­
cation of tenolysis (7%) and will necessitate a silicone rod
spacer and secondary tendon graft. Therefore delayed re­
pair with tendon graft or FDS transfer can be considered,
especially in severe crush or avulsion degloving injuries.5,8
Poor Sensory Recovery and Cold
Intolerance
Digital sensibility is an important functional goal. Return
of superficial pain and tactile sensibility throughout the
autonomous area with disappearance of overreaction (S3
or more) has been reported in up to 61% of thumb replan­
tation and 54% of finger replantation. The static two-point
discrimination (S2PD) is comparable between direct nerve
repair and nerve grafting.15
Moderate to severe cold intolerance has been reported
in more than 80% of digital replantations and usually abates
after a period of 2 years. It is worth noting, however, that
cold intolerance is less severe and less common when the

SECTION VIII THE HAND AND UPPER EXTREMITY
1270
vein may not be adequate, because the flow bypasses the flap
to revascularize the distal digit but does not perfuse the flap,
unlike the shunt-restriction venous flap modification.25,26
As for extensive soft tissue loss, coverage of vital struc­
tures such as tendons and vessels will necessitate a regional
flap such as the posterior interosseous flap or even a free
flap.7 Pedicled distant flaps may prevent early mobilization
and rehabilitation, leading to poor functional outcomes.
Thumb Replantation
The unfavorable outcomes of thumb replantation include
a nonsensitive thumb, a short thumb, a malpositioned
thumb, and replant loss.
Pearls of Wisdom
The surgeon should select the ulnar digital artery for perfu­
sion and consider an interpositional vein graft to the radial
artery at the snuff box. A sizable palmar vein can be identi­
fied in the pulp of the thumb superficial to the arteries, and
it is reliable. Bone shortening should be done judiciously.
Range of motion is less critical in thumb replantation com­
pared with finger replantation as long as the position is
correct. An IP arthrodesis can facilitate bone shortening
and prevent a painful, stiff, and flexed IP joint (Fig. 65.4).
Furthermore, a better functional outcome of the replanted
thumb is expected at the distal level than at the proximal
one.7,17,23,27,28
Transmetacarpal Replantation
The unfavorable outcomes of transmetacarpal replantation
are weak or absent intrinsic function, weak grip, poor sen­
sory recovery, tendon adhesion, joint contracture, intrinsic
tightness, and bone nonunion29 (Fig. 65.5).
Pearls of Wisdom
Despite a poor outcome after this particular amputation,
acceptable function can still be achieved (Fig. 65.6) if the
following are considered:
•• When revascularization with vein graft is needed, the
venous arch from the dorsal forefoot can be used. It is
important to test the venous valves with a heparinized
saline flush before the venous arch is used. The first
branch is designed for the thumb, which is more
important than other fingers. In this arrangement if
there is a problem in revascularization one of the fingers
but not the thumb may be lost.
•• The metacarpal bones should be evenly shortened
(12 to 15 mm), which may facilitate direct repair of the
retracted neurovascular bundles.
•• All damaged intrinsic musculature should be
excised. Correct thumb rotatory alignment
Replantation by Level of Amputation
or Mechanism of Injury
Distal Replantation
The unfavorable outcome of distal replantation is replant
loss. Survival at this level depends on the number of veins
repaired, not arteries. Replantation was shown to achieve
a more than 90% success rate when at least two veins were
repaired, compared with 75% when one vein or none was
repaired.16,19,20
Pearls of Wisdom
The surgeon should consider doing the artery first, because
veins could be absent or difficult. The volar venous plexus
is selected for zone I, and the dorsal veins are selected for
zone II amputations. When there are no veins, one of the
following strategies can be applied:
1. Arteriovenous shunting to the dorsal vein
2. Chemical leeches (nail bed bleeding with topical
­heparin application)
3. Heparin injection at the volar surface of the tip (cost-
effective)
4. Medical leeches (third-generation cephalosporin or
aminoglycosides are needed for prophylaxis)
5. A subdermal pocket
Vessels smaller than 0.7 mm are repaired using 11–0 su­
ture, starting at the back wall.16 For Tamai zone I at the
lunula, the transverse palmar arch or any of its branches
(preferably the central branch) can be used. The bifurcation
of this central branch can be further exploited for arterial
and venous vascularization.21 At Tamai zone II, the digital
arteries are used.15 Sensory repair may not be necessary
but should be performed when feasible.22
Ring Avulsion Injuries
The unfavorable outcomes of ring avulsion injuries are re­
plant loss related to a long segment of vascular injury and
skin necrosis, especially in Kay type III and IV injuries.7
Pearls of Wisdom
Vascular injury is best managed with vascular graft with­
out hesitation. Although arterial grafts can be used,23 ve­
nous grafts from the volar forearm are preferred, because
they have a comparable diameter, are readily available, and
could have a Y shape to enable two distal arteries based on
one proximal artery.
Skin necrosis limited to the dorsal aspect of one finger
can benefit from a venous flap, allowing simultaneous cover­
age and vascular reconstruction.24 However, the survival of a
large venous flap that depends on a flow-through arterialized

1271
Chapter 65 Replantation of the Hand and Toe-to-Hand Microsurgical Transplantation
Fig. 65.5 (a) Transmetacarpal amputation. (b,c) Poor intrinsic muscle function despite replantation success.
a
b
c
Fig. 65.4 (a) Ring avulsion amputation of the thumb. (b) After replantation with interphalangeal joint arthrodesis. (c,d) Good function
was restored at 1-year follow-up.
a
b
c
d
Fig 65.6 (a) Transmetacarpal amputation. (b–d) Good intrinsic function.
a
b
c
d

SECTION VIII THE HAND AND UPPER EXTREMITY
1272
Major Proximal Replantations
The unfavorable outcomes of major proximal replantations
include sepsis, poor limb function after extensive high-risk
surgery, and death from infection or reperfusion syndrome.
Pearls of Wisdom
Replantation should not be attempted when the potential
for functional gain is poor, such as in the proximal forearm,
unless a prehensile hand can be achieved and the patient’s
condition is stable. Similarly, amputations proximal to the
elbow should be considered only to salvage a functional
elbow joint in a stable patient. Reperfusion syndrome and
myoglobinemia can happen in above-elbow amputation
and can lead to death; therefore a wise decision is essen­
tial.
For wrist and more proximal amputations, when warm
ischemia time is more than 4 hours, priority is given to
temporary arterial shunting. Once arterial shunting is com­
pleted, the vein should be allowed to drain before it is con­
nected to the proximal circulation. The risk of exsangui­
nation is substantial; therefore matched blood should be
available.
Adequate débridement and copious irrigation is impor­
tant to prevent sepsis and subsequent replant loss or even
death.
should be maintained. Primary arthrodesis of the
metacarpophalangeal (MCP) joint should be avoided.
Early active mobilization with anticlaw splinting should
be considered during rehabilitation. Secondary tendon
transfer can be considered to compensate for the lost
intrinsic function.
Multiple-Digit Replantation
The unfavorable outcomes of multiple-digit replantation
are largely related to failure in achieving a viable thumb,
adequate web space, two viable adjacent fingers, and a
stable wrist.30
Pearls of Wisdom
As many digits as possible are replanted, starting with the
thumb and followed by the finger with the best chance
of function.31 Restoration of ulnar fingers should be at­
tempted and never disregarded because of their significant
role in grip function and hand closure. Fingers injured at
the MCP level and other nonreplantable fingers should be
considered for heterotransplantation and spare part sur­
gery. Functionally important digits that could not be re­
planted can be planned for future secondary toe-to-hand
transfer (Fig. 65.7).
Fig 65.7 (a,b) Successful replantation of 6 digits out of 10 and secondary second toe–to–left thumb transfer. (c,d) Good function was
achieved in the right hand with the replanted thumb and the left hand with the toe-to-thumb transfer. Note that the surgery achieved its
goals of a viable thumb, a minimum of viable two adjacent fingers, and successful reconstruction of an important digit: the left thumb.
a
b
c
d

1273
Chapter 65 Replantation of the Hand and Toe-to-Hand Microsurgical Transplantation
Toe-to-Hand for Multiple-Finger
Amputation
In multiple-finger amputation, especially proximal ampu­
tation with an intact thumb, unfavorable results could arise
from failure in reconstructing two adjacent fingers to pro­
vide a stable tripod pinch, a contracted first web space, or
length discrepancy (Fig. 65.8).
To avoid such complications, the selection of which two
adjacent fingers to replace should take into account the ad­
equacy of the first web space, functional demands (fine ma­
nipulation versus hook grip), the condition of the remaining
fingers, and the level of amputation (proximal or distal to
the web space). As a general rule, the index and long fingers
are reconstructed when the first web space is adequate and
fine manipulation is important. The long and ring fingers are
reconstructed when the first web space is tight or severely
scarred, so that the first ray can be amputated to widen the
web space. The ulnar fingers are reconstructed when hook
grip is needed.2,33–36
Toe-to-Hand for Metacarpal Hand
Amputation
The unfavorable results of a toe-to-hand transfer for a
metacarpal hand amputation may arise from inadequate
soft tissue coverage given the extensive nature of the in­
jury or failure in achieving tripod pinch because of poorly
selected and transplanted toes, a defective sequence of toe
transfer, or compromised thenar muscle function, espe­
cially in a complex type II metacarpal hand deformity.33,37
To avoid complications, the need for skin, muscle, or
bone should be determined before toe transfer. Selection
of the optimal recipient vessels, nerves, and tendons; the
dimension of the toe flap and the length of structures
transferred with the toe; and the need for a vein graft
and its length can allow uneventful surgery. A computed
tomography angiogram could be indicated in the setting
of severe traumatic injuries or congenital deformities,38
and three-dimensional models can help improve the pre­
cision of the surgery.39 Otherwise, a type I metacarpal
hand is dealt with similar to a proximal multiple-finger
amputation.
In a type II metacarpal hand, however, if the function
of the thenar muscles is adequate (subtypes IIA and IIB), si­
multaneous reconstruction of the thumb and two adjacent
fingers in one stage is preferable. If thenar muscle function is
inadequate (subtype IIC), a staged reconstruction is planned;
the fingers are reconstructed first, and a prosthetic thumb
post is used temporarily to assist in determining the length
and position of the transferred toe for thumb reconstruction
during the second stage40,41 (Fig. 65.9).
Microsurgical
Toe-to-Hand Transfer
Avoiding Unfavorable
Outcomes and Complications
in Microsurgical Toe-to-Hand
Transfer
Summary Box
Unfavorable Outcomes and Complications
Associated with Microsurgical Toe-to-Hand
Transfers
•• Inappropriate anatomical position or osteosynthesis
•• Wrong tendon repair, rupture, and adhesion
•• Poor joint motion
•• Poor sensation
•• Unfavorable appearance
•• Unfavorable donor site
•• Extension lag and flexion deformity of the second
toe transferred to the thumb
•• Toe flap loss
Similar to replantation, unfavorable outcomes after toe-to-
hand transfer are a result of defective planning and erro­
neous surgical execution. Optimization of the surgical plan
and performance are essential to restore the lost form and
function and prevent unfavorable outcomes.
Planning, Decision-Making, and
Preparation
Thorough planning addressing the number and location of
transferred toes is essential to achieving improved prehen­
sion, useful tripod pinch and stronger hook grip, lateral
stability, handling precision, and enhanced appearance
(Videos 65.1-65.4).
Toe-to-Hand for Single-Finger
Amputation
The untoward outcome of a toe-to-hand single-finger
transfer could be length discrepancy with the remaining
fingers, particularly with proximal amputation of the index
or long finger. To avoid this, we advise against toe transfer
in such cases.

SECTION VIII THE HAND AND UPPER EXTREMITY
1274
toe or combined third and fourth toe transplantation) while
the nondominant hand receives bipod reconstruction (two
separate lesser toes) (Fig. 65.10).
In a bilateral type II metacarpal hand, the most severe
form of injury, the dominant hand can benefit from tripod
reconstruction (great toe plus combined second and third
Fig. 65.9 (a) A metacarpal hand type II with intrinsic muscle injury, after a staged pedicled groin and combined second and third toe trans­
fer. (b) A prosthetic post to determine the location and length of the great toe. (c) The well-balanced hand after great toe transfer.
a
b
c
Fig. 65.10 (a) Bilateral type II metacarpal hand injury. (b) The dominant hand first received combined second- and third-toe transfer and
then a whole great-toe transfer to reconstruct a stable tripod pinch. (c) The nondominant hand received third- and fourth-toe transplanta­
tion to reconstruct a bipod pinch. (d) Minimal donor site morbidity, at 25-year follow-up.
a
b
c
d
Fig. 65.8 (a) Proximal amputation of the long and ring fingers. (b) Length discrepancy after bilateral second toe transfer.
a
b

1275
Chapter 65 Replantation of the Hand and Toe-to-Hand Microsurgical Transplantation
Third, the surgeon must choose whether to use zone III for
flexor tendon repair or limit tendon repair to the FDP only
if it must be done in zone II.
When adhesion becomes a problem despite adequate
hand therapy, tenolysis is indicated, starting with the exten­
sor followed by the flexor tendon. During tenolysis, in partic­
ular for the flexor tendons, meticulous dissection should be
maintained so injury to the toe vascular pedicle and nerves
is avoided. Sometimes the passive range of motion remains
restricted at the MCP joint and/or PIP joint despite extensor
tenolysis; in such a case, dorsal capsulotomy and excision
of dorsal collateral ligaments can help. Simultaneous lysis
is avoided to prevent edema and stiffness.14,43
In one study the need for secondary procedures on ten­
don, bone, joints, and soft tissue was 9.0%, 1.5%, 2.3%, and
3.8%, respectively.43 Tenolysis was the secondary procedure
most commonly performed (6.8%), followed by arthrodesis
(3.0%) and web space deepening (3.0%). In our experience,
secondary procedures yield satisfactory results, particularly
flexor tendon tenolysis.
Poor Joint Motion
Unstable bony fixation and prolonged immobilization can
contribute to poor joint motion. Therefore it is of utmost
importance to start rehabilitation of joints proximal and
distal to the repair site as early as possible and to proceed
with a dedicated progressive hand therapy protocol.
Pearls of Wisdom
Transfer of the metatarsophalangeal joint has been de­
scribed to increase toe length when the first metacarpal is
missing. However, this joint is an extension joint that flexes
poorly, and therefore we do not recommend inclusion of a
lengthy metatarsus unless for aplastic thumb reconstruc­
tion. Furthermore, transmetatarsal osteotomy will neces­
sitate extensive dissection resulting in foot destruction and
donor pain or discomfort. Missing length can be restored
using a bone graft from the iliac crest at the time of groin
flap transfer for adequate soft tissue coverage. An oblique
Managing Unfavorable Results
and Complications in Toe-to-
Hand Microsurgical Transfer
Toe-to-hand transfer is a reliable microsurgical procedure
that can yield satisfactory functional and aesthetic out­
comes.
Inappropriate Anatomical Position
or Osteosynthesis
To achieve optimal position, the toe should be pronated
into appropriate opposition, and the web space should be
adequate to allow supple movement and grasping of large
objects.2–4 Bone fixation should be fast, requires minimal
soft tissue dissection, and maintains skeletal length as well
as the joint. Ideally, stable but not rigid fixation is preferred
to allow correction of any malrotation or angulation with­
out having to redo fixation.42,43
Pearls of Wisdom
Interosseous wiring can fulfill the requirements of proper
anatomical position and good osteosynthesis (Fig. 65.11).
Using this approach, the overall nonunion rate of 1.5% was
observed after a mean follow-up of 30 months.42,43
Wrong Tendon Repair, Rupture, and
Adhesion
To achieve the correct tendon repair, the extensor tendons
should be repaired tightly with the MCP joint and the prox­
imal interphalangeal (PIP) joint in full extension to mini­
mize flexion deformity, and the flexor tendons should be
repaired in a way that prevents entrapment of the tenor­
rhaphy site by the remaining pulleys during tendon excur­
sion; therefore only the flexor digitorum profundus (FDP)
is repaired preferably at zone I and III for fingers and 2 cm
proximal to the A1 pulley for the thumb. Finally, tension
between extensor and flexor mechanisms should be ad­
justed so that the finger forms a natural cascade with the
other digits.
Rupture of the repaired tendon is very uncommon.4,43
When the extensor tendon is ruptured, it does not usually
retract; therefore minimal elevation is required for repair.
Flexion tendon rupture will necessitate wider exposure to
retrieve the retracted proximal end and may require a ten­
don graft.
Tendon adhesion is almost inevitable; however, the ex­
tent of adhesion can be minimized. An important key step is
to provide stable osteosynthesis that permits early mobili­
zation and intensive supervised progressive hand therapy.14
The second important step is smoothing the bony fixation
site and placing the tenorrhaphy away from any sharp edges.
Fig. 65.11 Interosseous wiring, with preservation of the joints.

SECTION VIII THE HAND AND UPPER EXTREMITY
1276
toe transplant should be very neat to avoid a bulky look and
open tunnels with increased scars. Tunnels and small ac­
cess wounds placed away from the site of transplantation
are always preferred to avoid excessive scarring and inferior
appearance.49
When the great toe is stout compared with the contra­
lateral thumb, a trimmed great toe is advocated. Although
a modest reduction in IP joint movement may be expected,
the overall function and usefulness have been good50 (Fig.
65.13).
The bulbous tip of the second and great toes will benefit
from pulpplasty, which will also improve sensory return.51
Unfavorable Donor Site
Complications arising at the donor site will increase pa­
tient donor site morbidity and decrease satisfaction despite
functional gain in the hand. Delayed wound healing, skin
necrosis, hypertrophic scars, painful neuromas, scissoring
deformity, widening of a web space, and weak push-off are
serious problems and should be avoided.
metatarsal osteotomy may help realign the thumb MCP
into a flexor joint.
A tight web space can also limit the range of motion
of intact joints, leading to compromised function and even
stiffness of the restricted joints and creating a vicious cycle
that is hard to break. The adequacy of the web space should
be assessed before toe transfer at the time of soft tissue cov­
erage. In our experience, only 2.3 to 3% of the patients re­
quired a secondary procedure for joint stiffness.43
Poor Sensation
Most transplants will regain useful sensation with two-
point discrimination of less than 15 mm, or at least protec­
tive sensation.44–46
Pearls of Wisdom
Neuroma should be carefully excised; the toe digital nerves
are then coapted to healthy recipients, confirmed under
microscope, using 10–0 nylon. Nerve graft or vein graft can
be used to provide tension-free repair. End-to-end repair is
still the preferred method of coaptation. When end-to-end
repair is not possible, because of avulsion injury for exam­
ple, a dorsal sensory nerve can be selected instead. Long
nerve grafts are avoided.
Another important key factor for better sensory return is
biphasic sensory reeducation.47 The early phase that focuses
on perception of touch submodalities and the late phase of
reeducation targeting size, shape, and object recognition
play a substantial role in sensory improvement with an av­
erage of 7 mm in static two-point discrimination and 6 mm
in moving two-point discrimination in our experience.48
Unfavorable Appearance
Although microsurgical toe transfer will yield good func­
tional results in different types of hand amputation, in par­
ticular, thumb and distal finger amputations, the toe will
look like a toe. The inherent features of the second toe such
as short neck, bulbous tip, and broad and short nail will
make the difference with the remaining fingers and thumb
quite striking. Furthermore, the pudgy great toe is not an
exception; it will hardly look like a thumb.
Aside from the inherent toe characteristics, skin grafts,
scars, and bulky toe transplants will definitely worsen the
appearance, leading to dissatisfaction.
Pearls of Wisdom
To maximize aesthetics, we advocate careful assessment of
the appearance of the great and second toe compared with
the contralateral thumb and the remaining fingers to select
the toe that has the better resemblance, when possible.
The stump can also be prepared using zig zag flaps to
interdigitate the stump skin with the toe skin and avoid the
ugly cobra head appearance (Fig. 65.12). Furthermore, the
Fig. 65.12 Cobra head deformity.
Fig. 65.13 Left thumb reconstruction with a trimmed great toe. The
difference is hard to distinguish.

1277
Chapter 65 Replantation of the Hand and Toe-to-Hand Microsurgical Transplantation
of the proximal phalanx distal to the MCP joint is preserved.
We do not advocate shortening the first metatarsus or first
metatarsal head removal, because both of these maneuvers
will transfer the load laterally and may cause lateral meta­
tarsalgia.4
Painful neuroma can be prevented by proximal resection
of the nerves and by burying the nerve ends in the muscle.
Finally, unstable coverage at the dorsum of the foot
should be corrected, preferably using a thin pliable free skin
flap such as a medial sural artery perforator flap or a lateral
arm flap52,53 (Fig. 65.15).
Extension Lag and Flexion Deformity of
the Second Toe Transferred to Thumb
Using the second toe for thumb reconstruction has the dis­
tinct advantage of minimal donor site morbidity. However,
the second toe falls short compared with the great toe aes­
thetically and functionally.
Pearls of Wisdom
Destructive dissection should be avoided, which is why we
recommend dividing the tendon of the long flexor of the
toe not at the ankle but at the midfoot, and for the same
reason the plantar pedicle is divided at the same level and a
vein graft is used if the pedicle is short4 (Fig. 65.14).
We prefer not to include a wide skin paddle with the
toe flap to avoid a skin graft or tight repair at the foot. Inad­
equate soft tissue at the recipient site is better addressed by
distant pedicled flaps at a prior stage.
After second toe transfer, the deep transverse metatar­
sal ligament should be repaired to decrease tension, and
skin can be trimmed to narrow the new web for better cos­
mesis. In combined second and third toe transfer, however,
the deep ligament is not repaired to avoid distortion of the
fourth metatarsal head, and the skin is not trimmed to allow
tension-free repair of the web space.4
To improve cosmesis after great toe transfer and most
importantly to allow good push-off from the ground, 1 cm
Fig. 65.14 Scissoring deformity after combined second and third
toe harvest because of destructive dissection in a case of dorsal
metatarsal plantar artery dominance.
Fig. 65.15 (a) Necrosis of the foot dorsal skin after great toe transfer, managed with skin graft. (b) Lateral arm flap after 1-year follow-up.
a
b
Fig. 65.16 Second toe transfer to the thumb, resulting in double joints and a clawing deformity. The position is nonetheless correct.
a
b

SECTION VIII THE HAND AND UPPER EXTREMITY
1278
Combined second and third toe transfer deserves spe­
cial note, because toe loss could be the result of inadequate
inflow after a single-artery repair; therefore it is advised in
this particular transplant to prepare two arteries and do two
sets of arterial anastomoses at any sign of vascular insuffi­
ciency (Fig. 65.17).
In the case of partial toe transfer for distal amputation,
the failed toe can be deepithelialized and covered with
dermal skin flaps from the groin or the abdomen (dermal
pocket).
In the case of whole toe transfer for proximal amputa­
tion, the failed toe is removed, the patient is given time to
recover the psychological shock, and the underlying problem
is identified and addressed totally. After that the patient is
prepared for another toe transfer. In these situations, the toe
flap of choice is usually a second toe flap after either failure
of the great or second toe. If the patient rejects another toe
transfer, the stump is closed definitively, often requiring a
distant pedicled flap. We have no preference for using local
or regional pedicled flaps.
Conclusion
Unfavorable results are the bitter fruit of poor planning,
defective decision-making, inadequate preparation, and
erroneous surgery. Identifying unfavorable results after re­
plantation and toe-to-hand microsurgical transplantation
is experience—demanding but essential for an improved
level of care and favorable reconstruction that together
can yield satisfactory functional and aesthetic outcomes
and higher patient satisfaction, leading to the ultimate
goal of improved patient quality of living and cost-effective
­treatment.
The second toe has two IP joints instead of one. It also
has a greater tendency to claw and develop flexion contrac­
ture (Fig. 65.16).
The tendency to claw can be prevented by releasing the
extensor digitorum longus attachment from the metatarso­
phalangeal joint, suturing the extensor digitorum brevis to
the extensor hood or interosseous tendon, tight extensor re­
pair, pinning interphalangeal joints in extension for 6 weeks,
and nighttime extension splints for at least 1 year.4 Distal IP
joint clawing can be corrected with arthrodesis. However,
the results of these preventative measures are inconsistent.
Based on better understanding of the anatomy of the
second toe, if full extension of the proximal interphalan­
geal joint can be achieved by pulling the extrinsic exten­
sors, a tight repair of the corresponding tendon can prevent
extension lag. However, if the proximal interphalangeal
joint can only be extended through passive flexion of the
­metatarsophalangeal joint or when both extrinsic and in­
trinsic tendons are pulled simultaneously, the lateral bands
should be addressed.53,54 Although the technique has been
described in vascularized joint transfer only, it can still be
useful in lesser toe transfer to correct extension lag and pre­
vent clawing.
Toe Flap Loss
Total failure of the transplanted toe is the most dreaded
untoward result. Every effort should be made to prevent
failure intraoperatively and postoperatively and to salvage
a failing toe. In our experience, total failure was 3%, reex­
ploration rate was 21.4%, and the salvage rate was 89%. In­
fection was the single greatest risk factor for takebacks and
failure.25, 55
Fig. 65.17 (a) Toe necrosis after combined second and third toe transfer related to single-artery anastomosis. (b) Acceptable function with
notable partial loss of the third toe, at 17-year follow-up.
a
b
References
1. American Replantation Mission to China. Replantation
surgery in China. Plast Reconstr Surg 1973;52:476–489
2. Wei FC, Jain V, Chen SHT. Toe-to-hand transplantation.
Hand Clin 2003;19(1):165–175
3. Wei FC, el-Gammal TA. Toe-to-hand transfer. Current
concepts, techniques, and research. Clin Plast Surg 1996;
23(1):103–116
4. Buncke HJ, Buncke GM, Kind GM, Buntic RF. Revascu­
larisation and Replantation and Toe to Hand Transfer. In:
Goldywn RM, Cohen MN, eds. The Unfavorable Result in
Plastic Surgery: Avoidance and Treatment. 3rd ed. Phila­
delphia: Lippincott, Williams & Wilkins; 2001:800–804
5. Sabapathy SR, Venkatramani H, Bharathi RR, Bhardwaj
P. Replantation surgery. J Hand Surg Am 2011;36(6):
1104–1110
6. Corbitt C, Skoracki RJ, Yu P, Hanasono MM. Free flap fail­
ure in head and neck reconstruction. Head Neck 2014;
36(10):1440–1445

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Chapter 65 Replantation of the Hand and Toe-to-Hand Microsurgical Transplantation
27. Daoutis N, Efstathopoulos D, Gerostathopoulos N, et al.
Replantation of the thumb: survival rate and functional
recovery in correlation with type of injury. Microsurgery
1993;14(7):454–456
28. Sharma S, Lin S, Panozzo A, Tepper R, Friedman D. Thumb
replantation: a retrospective review of 103 cases. Ann
Plast Surg 2005;55(4):352–356
29. Weinzweig N, Sharzer LA, Starker I. Replantation and re­
vascularization at the transmetacarpal level: long-term
functional results. J Hand Surg Am 1996;21(5):877–883
30. Baek SM, Kim SS. Ten-digit and nine-digit replantation
(4 cases). Br J Plast Surg 1992;45(6):407–412
31. Wei FC, Chuang CC, Chen HC, Tsai YC, Noordhoff MS.
Ten-digit replantation. Plast Reconstr Surg 1984;74(6):
826–832
32. Dzwierzynski WW. Replantation and Revascularization.
In: Neligan PC, ed. Plastic Surgery. 3rd ed. New York: Else­
vier; 2013:228–249
33. Wei FC, el-Gammal TA, Lin CH, Chuang CC, Chen HC, Chen
SH. Metacarpal hand: classification and guidelines for
microsurgical reconstruction with toe transfers. Plast Re­
constr Surg 1997;99(1):122–128
34. Wei FC, Colony LH. Microsurgical reconstruction of op­
posable digits in mutilating hand injuries. Clin Plast Surg
1989;16(3):491–504
35. Wei FC, Coessens B, Ganos D. Multiple microsurgical toe-
to-hand transfer in the reconstruction of the severely mu­
tilated hand. A series of fifty-nine cases. Ann Chir Main
Memb Super 1992;11(3):177–187
36. Wei FC, Colony LH, Chen HC, Chuang CC, Noordhoff MS.
Combined second and third toe transfer. Plast Reconstr
Surg 1989;84(4):651–661
37. Mardini S, Wei FC. Unilateral and bilateral metacarpal
hand injuries: classification and treatment guidelines.
Plast Reconstr Surg 2004;113(6):1756–1759
38. Jones NF, Hansen SL, Bates SJ. Toe-to-hand transfers for
congenital anomalies of the hand. Hand Clin 2007;23(1):
129–136
39. Tan H, Yang K, Wei P, et al. A novel preoperative planning
technique using a combination of CT angiography and
three-dimensional printing for complex toe-to-hand re­
construction. J Reconstr Microsurg 2015;31(5):369–377
40. Wei FC, Lutz BS, Cheng SL, Chuang DCC. Reconstruction of
bilateral metacarpal hands with multiple-toe transplan­
tations. Plast Reconstr Surg 1999;104(6):1698–1704
41. Tan BK, Wei FC, Lutz BS, Lin CH. Strategies in multiple toe
transplantation for bilateral type II metacarpal hand re­
construction. Hand Clin 1999;15(4):607–612, viii
42. Yim KK, Wei FC. Intraosseous wiring in toe-to-hand
transplantation. Ann Plast Surg 1995;35(1):66–69
43. Yim KK, Wei FC. Secondary procedures to improve func­
tion after toe-to-hand transfers. Br J Plast Surg 1995;48(7):
487–491
44. Chu NS, Wei FC. Recovery of sensation and somatosen­
sory evoked potentials following toe-to-digit transplanta­
tion in man. Muscle Nerve 1995;18(8):859–866
45. Chung KC, Wei FC. An outcome study of thumb recon­
struction using microvascular toe transfer. J Hand Surg
Am 2000;25(4):651–658
46. Lin CH, Lin YT, Sassu P, Lin CH, Wei FC. Functional assess­
ment of the reconstructed fingertips after free toe pulp
transfer. Plast Reconstr Surg 2007;120(5):1315–1321
47. Dellon AL. Sensory recovery in replanted digits and trans­
planted toes: a review. J Reconstr Microsurg 1986;2(2):
123–129
7. Chen HC, Tang YB. Replantation of the thumb, especially
avulsion. Hand Clin 2001;17(3):433–445
8. Tamai S. Twenty years’ experience of limb replantation—
review of 293 upper extremity replants. J Hand Surg Am
1982;7(6):549–556
9. Tark KC, Kim YW, Lee YH, Lew JD. Replantation and re­
vascularization of hands: clinical analysis and functional
results of 261 cases. J Hand Surg Am 1989;14(1):17–27
10. Wei FC, Epstein MD, Chen HC, Chuang CC, Chen HT. Mi­
crosurgical reconstruction of distal digits following muti­
lating hand injuries: results in 121 patients. Br J Plast Surg
1993;46(3):181–186
11. Küntscher MV, Erdmann D, Homann HH, Steinau HU,
Levin SL, Germann G. The concept of fillet flaps: classi­
fication, indications, and analysis of their clinical value.
Plast Reconstr Surg 2001;108(4):885–896
12. Yim KK, Wei FC, Lin CH. A comparison between primary
and secondary toe-to-hand transplantation. Plast Recon­
str Surg 2004;114(1):107–112
13. Brown ML, Wood MB. Techniques of bone fixation in re­
plantation surgery. Microsurgery 1990;11(3):255–260
14. Jupiter JB, Pess GM, Bour CJ. Results of flexor tendon te­
nolysis after replantation in the hand. J Hand Surg Am
1989;14(1):35–44
15. Glickman LT, Mackinnon SE. Sensory recovery following
digital replantation. Microsurgery 1990;11(3):236–242
16. Chen CT, Wei FC, Chen HC, Chuang CC, Chen HT,
Hsu WM. Distal phalanx replantation. Microsurgery
1994;15(1):77–82
17. Arakaki A, Tsai TM. Thumb replantation: survival factors
and re-exploration in 122 cases. J Hand Surg [Br] 1993;
18(2):152–156
18. Hovius SE, van Adrichem LN, Mulder HD, van Strik R, van
der Meulen JC. Comparison of laser Doppler flowmetry
and thermometry in the postoperative monitoring of re­
plantations. J Hand Surg Am 1995;20(1):88–93
19. Cheng GL, Pan DD, Yang ZX, Qu ZY. Replantation of dig­
its amputated at or about the distal interphalangeal joint.
Ann Plast Surg 1985;15(6):465–473
20. Yamano Y. Replantation of the amputated distal part of
the fingers. J Hand Surg Am 1985;10(2):211–218
21. Hsu CC, Lin YT, Moran SL, Lin CH, Wei FC, Lin CH. Arterial
and venous revascularization with bifurcation of a single
central artery: a reliable strategy for Tamai Zone I replan­
tation. Plast Reconstr Surg 2010;126(6):2043–2051
22. Wong C, Ho PC, Tse WL, Cheng S, Chan DK, Hung LK. Do
we need to repair the nerves when replanting distal
finger amputations? J Reconstr Microsurg 2010;26(5):
347–354
23. Janezic TF, Arnez ZM, Solinc M, Zaletel-Kragelj L. One hun­
dred sixty-seven thumb replantations and revascularisa­
tions: early microvascular results. Microsurgery 1996;
17(5):259–263
24. Tsai TM, Matiko JD, Breidenbach W, Kutz JE. Venous flaps
in digital revascularization and replantation. J Reconstr
Microsurg 1987;3(2):113–119
25. Lam WL, Lin WN, Bell D, Higgins JP, Lin YT, Wei FC. The
physiology, microcirculation and clinical application of
the shunt-restricted arterialized venous flaps for the
reconstruction of digital defects. J Hand Surg Eur Vol
2013;38(4):352–365
26. Lin YT, Henry SL, Lin CH, et al. The shunt-restricted ar­
terialized venous flap for hand/digit reconstruction: en­
hanced perfusion, decreased congestion, and improved
reliability. J Trauma 2010;69(2):399–404

SECTION VIII THE HAND AND UPPER EXTREMITY
1280
53. Lam WL, Waughlock N, Hsu CC, Lin YT, Wei FC. Improv­
ing the extensor lag and range of motion following free
vascularized joint transfer to the proximal interphalan­
geal joint: Part 2. A clinical series. Plast Reconstr Surg
2013;132(2):271e–280e
54. Waughlock N, Hsu CC, Lam WL, Lin YT, Wei FC. Improving
the extensor lag and range of motion following free vas­
cularized joint transfer to the proximal interphalangeal
joint: Part 1. An observational and cadaveric study. Plast
Reconstr Surg 2013;132(2):263e–270e
55. Lin YT, Su ST, Lo S, Hu CH, Lin CH, Wei FC. Risk factors
for reexploration in toe-to-hand transfer: a multivariate
analysis of 363 cases. Plast Reconstr Surg 2015;135(2):
501–506
48. Wei FC, Ma HS. Delayed sensory reeducation after toe-
to-hand transfer. Microsurgery 1995;16(8):583–585
49. Wallace CG, Wei FC. Further aesthetic refinement for great
toe transfers. J Plast Reconstr Aesthet Surg 2010;63(1):
e109–e11
50. Wei FC, Chen HC, Chuang CC, Noordhoff MS. Reconstruc­
tion of the thumb with a trimmed-toe transfer technique.
Plast Reconstr Surg 1988;82(3):506–515
51. Wei FC, Yim KK. Pulp plasty after toe-to-hand transplan­
tation. Plast Reconstr Surg 1995;96(3):661–666
52. Ulusal BG, Lin YT, Ulusal AE, Lin CH. Free lateral arm flap
for 1-stage reconstruction of soft tissue and composite
defects of the hand: A retrospective analysis of 118 cases.
Ann Plast Surg 2007;58(2):173–178
Discussion by Luis R. Scheker
The determination not to replant an amputated part
is made after evaluating the part and the stump. Ex­
plaining to a patient and his or her relatives that a part
cannot be replanted is difficult, especially for those pa­
tients coming from a long distance or at great cost. The
initial evaluation is performed in the referring center,
where experience may be lacking regarding “damage
beyond repair” (a determination that can be made only
after examination under magnification, unless it is ap­
parent to the naked eye that the part is grossly crushed
or destroyed). Only the senior member of an operative
group should discuss this prognosis with the patient
and the relatives.
The indications for single-finger replantation are ex­
panding: On one side is the functional and cosmetic as­
pect that the patient wants to achieve, and on the other
side is the need for the surgeon to provide the digital
nerve with nerve endings to reduce the occurrence of
painful neuromas, which are difficult to treat.
It is possible to perform anastomosis of vessels
measuring a fraction of a millimeter. Using the open
book technique of Morrison and McCombe,1 partially
obliquely amputated digital tips can be replanted, giv­
ing the patient the best possible outcome, and sacrificing
tissue from another part of the body is not necessary.
This type of replantation can be achieved in sharp
amputations. The distal part has a K-wire inserted ret­
rograde, embedded in the bone for later fixation. The
artery and vein in the proximal part are identified and
clamped (Fig. 65D.1). The fingerprints of the pulp of
the finger are aligned and the palmar skin sutured to
stabilize the amputated part. The anastomosis is then
performed from the dorsum. Stitches are placed to both
sides of the initial sutures on the palmar skin to approxi­
mate the structures to be anastomosed: (1) the artery
and then (2) the vein. This allows the surgeon to identify
the distal vein when it begins to bleed. The nerves here
are very small. The distal stumps are thus identified and
the patient recovers acceptable sensation, typically bet­
ter than 10-mm two-point discrimination.
After repair of deep structures, the skin is sutured
completely. The K-wire is advanced to fix the distal pha­
lanx, and the whole arm is placed in a bulky, occlusive
dressing for 2 weeks (Fig. 65D.2).
Fig. 65D.1 Replantation of segments of the distal end can be
achieved with the “open book technique.” The patient is then
placed in a bulky occlusive dressing, because there is no pos­
sibility of redoing the anastomosis.
Fig. 65D.2 The thumb looks normal and the nail is growing
without a longitudinal ridge. The results are very rewarding, but
the waiting period to see if the part survives can be agonizing
for the patient and the surgeon.

1281
Chapter 65 Replantation of the Hand and Toe-to-Hand Microsurgical Transplantation
The surgeon must inform the patient before the pro­
cedure that there is only one chance of repairing these
small structures. Should the replantation fail, a partial
toe transfer will be needed to reconstruct the defect.
When replantation is not possible, a second toe transfer
should be performed to restore function.
The unfavorable result of a bulbous tip of the trans­
ferred second toe, as mentioned in the chapter, is not
cosmetically pleasant and tends to have too much soft
tissue, making some activities, such as playing a stringed
instrument, too difficult. The tip of the transferred toe
thus needs debulking to approximate normal function
(Fig. 65D.3).
It is beneficial to excise the distal intrinsic muscles
during transmetacarpal replantation, because there is
no innervation and possibly inadequate blood supply
to the distal part. The surgeon must remove the muscle
only, preserving the intrinsic tendons so they will heal
in intrinsic plus position and avoid clawing of the fin­
gers. To achieve this, an anticlaw splint is applied within
the first 72 hours after replantation, with the MCP
joints in flexed position. A light extension crane splint
is added to prevent PIP joint contracture2 (Fig. 65D.4).
The deep palmar arch is seldom anastomosed; therefore
the branches must be ligated to prevent hematoma that
complicates recovery.
Conclusion
Microsurgical reconstruction is very demanding for the
patient and the surgeon, but the results can be very re­
warding.
As the late Professor Robert Acland said, “Planning
is the only shortcut in microsurgery,” (personal commu­
nication). The primary reconstructive goal for patients
who sustain devastating extremity injuries should be
to return function to the digits, because such injuries
change the patient’s quality of life even if they are not
life-threatening. A new frontier has been opened for
individuals with severe bilateral hand amputations in
which replantation or reconstruction with multiple toe
transfer is not possible (because the amputation is at
the carpus or proximal, or the amputated parts are de­
stroyed). The success achieved in hand transplantation
makes this procedure a viable possibility; hopefully fur­
ther research will eliminate the complications of organ
rejection and the enormous expense of transplantation
may be mitigated.
Fig. 65D.3 This professional violin player sustained an amputa­
tion of the distal phalanx of the left ring finger and damage to
the index and long fingers with a lawn mower. He had a second
toe transfer to the distal ring finger, and the long finger pulp was
augmented with the tissue excised from the toe pulp.
Fig. 65D.4 The extensor crane added to the anticlaw splint pre­
vents proximal interphalangeal joint contracture and allows the
patient to start early range of motion without rupture of the
extensor tendons, which are typically much weaker than the
flexor tendons.
References
1. Morrison WA, McCombe D. Digital replantation. Hand
Clin 2007;23(1):1–12
2. Scheker LR, Chesher SP, Netscher DT, Julliard KN, O’Neill
WL. Functional results of dynamic splinting after trans­
metacarpal, wrist, and distal forearm replantation.
J Hand Surg [Br] 1995;20(5):584–590

1282
CHAPTER
66
Many factors contribute to the final outcome in nerve sur­
gery. These same considerations apply to reconstructive
surgery in general, but the difference in nerve surgery is
that success or failure will commonly not be evident for
6 to 12 months or longer because of the slow rate of nerve
regeneration and target organ reinnervation and recovery.
If restoration of motor function is not successful, there
will not be a second chance to reinnervate target muscles
because of degeneration of the neuromuscular junction and
irreversible architectural changes in muscle structure. Even
if there is a significant loss of sensation and function after
a nerve injury, it is often the painful sequelae that have the
largest impact on patient lifestyle in the long term and are
the most difficult to manage. Therefore every effort is made
in nerve reconstruction to optimize axonal regeneration and
target end-organ reinnervation.
Factors that influence functional outcomes after nerve
surgery include the following:
•• Patient selection
•• Timing and choice of surgical procedure
•• Technical factors associated with the common
techniques of nerve repair and grafting
•• Rehabilitation
Avoiding Unfavorable Results
and Complications in Nerve
Surgery
Patient Selection
In posttraumatic reconstructive surgery, a patient with an
anatomically consistent sensory or motor deficit and sup­
porting electrodiagnostic studies is in general a good surgi­
cal candidate with realistic expectations. Management of
these patients is often straightforward. When treating a
patient with chronic pain of potentially neurologic origin
from either a previous injury or surgical intervention or a
possible compression neuropathy, determining appropri­
ateness for surgical intervention can become more chal­
lenging. A patient who presents with symptoms who has a
significant psychological barrier or unrealistic expectations
is unlikely to have a successful outcome regardless of the
surgeon’s skill and the technical success of the procedure.
A patient with neurologic symptoms may have secondary
gain from their symptoms, may be demonstrating atten­
tion-seeking behavior, or may have a psychiatric diagnosis.
How the patient responds to pain can have a significant im­
pact on functional recovery and rehabilitation, and there­
fore a large effect on the final outcome.1
The symptom of pain may have originated from a single
incident or traumatic event but may have several sources
that are often multiple and coexistent. Therefore it is critical
that a patient with an essentially isolated neuroma-related
pain be distinguished from a patient with a concomitant
pain syndrome. A variety of tools exist to evaluate pain se­
verity, including verbal scales, numeric scales, and the visual
analog scale (VAS).2–4 Multidimensional patient-reported
questionnaires are commonly used to evaluate pain qualities
and severity.5 A pain diagram is helpful to visualize the ana­
tomical location and extent of a patient’s pain, and an appro­
priate questionnaire will help determine the impact of the
pain on a patient’s lifestyle, activities of daily living (ADL),
and expectations of how and to what extent possible sur­
gery may improve the symptoms and their lives6 (Fig. 66.1).
A pain evaluation questionnaire can also be very helpful in
sorting out which patients are most appropriate for surgical
intervention. If the patient’s history and examination are not
definitive or are unclear and there is a suspicion of possible
malingering, numerous examination techniques can be used,
including rapid alternating movements, rapid grip exchange,
simultaneous tasks, and assessment of intratest variability.7,8
Peripheral Nerve Injuries and the
Brachial Plexus
Thomas H. Tung and Susan E. Mackinnon

1283
Chapter 66 Peripheral Nerve Injuries and the Brachial Plexus
WUP PLAS SEM PAIN QUE A NL (Rev 05/15)
Pain Questionnaire
Name
Date
/ /
Age_____ Sex:  Male  Female Dominant Hand:  Right  Left Diagnosis ____________________________
1.
Pain is difficult to describe. Check the words that best describe your symptoms:
 Burning
 Throbbing
 Aching
 Stabbing
 Tingling
 Twisting
 Squeezing
 Cramping
 Cutting
 Shooting
 Numbing
 Vague
 Stinging
 Indescribable
 Pulling
 Smarting
 Pressure
 Coldness
 Dull
 Other______________________
LEVEL OF SYMPTOMS
Check to indicate the level of your pain, with zero being no pain and 10 the most severe pain you can imagine
having.
2.
Mark your average level of pain in the last month:
No Pain
Most Severe Pain
3.
Mark your worst level of pain in the last week:
Right
No Pain
Most Severe Pain
Left
No Pain
Most Severe Pain
7.
Mark on this scale how depressed you currently feel:
0% (Not at All)
100% (A Large Amount)
5.
Mark on this scale how your pain has affected your quality of life:
0% (Not at All)
100% (A Large Amount)
4.
Where is your pain? (Draw on diagram):
6.
Mark on this scale how sad you are:
0% (Not at All)
100% (A Large Amount)
8.
Mark on this scale how frustrated you currently feel:
0% (Not at All)
100% (A Large Amount)
9. Mark on this scale how angry you currently feel:
0% (Not at All)
100% (A Large Amount)
Fig. 66.1 Pain questionnaire that includes a visual analog scale. (Reproduced from Washington University School of Medicine, St. Louis,
MO, with permission.)
Continued

SECTION VIII THE HAND AND UPPER EXTREMITY
1284
12. How well are you able to cope with that stress:
At Home
Very Well
Not at All
At Work
Very Well
Not at All
13. How did the pain that you are now experiencing occur?

a. Sudden onset with accident or definable event

b. Slow progressive onset

c. Slow progressive onset with acute exacerbation without an accident or definable event

d. A sudden onset without an accident or definable event
14. How many surgical procedures have you had in order to try to eliminate the cause of your pain?

a. None or one

b. Two surgical procedures

c. Three or four surgical procedures

d. Greater than four surgical procedures
15. Does movement have any effect on your pain?

a. The pain is always worsened by use or movement

b. The pain is usually worsened by use and movement

c. The pain is not altered by use and movement
16. Does weather have any effect on your pain?

a. The pain is usually worse with damp or cold weather.

b. The pain is occasionally worse with damp or cold weather.

c. Damp or cold weather has no effect on the pain.
17. Do you ever have trouble falling asleep or awaken from sleep?

a. No - Proceed to Question 19

b. Yes - Proceed to 18A & 18B
18A. How often do you have trouble falling asleep?

a. Trouble falling asleep every night due to pain

b. Trouble falling asleep due to pain most nights of the week

c. Occasionally having difficulty falling asleep due to pain

d. No trouble falling asleep due to pain

e. Trouble falling asleep which is not related to pain
18B. How often do you awaken from sleep?

a. Awakened by pain every night

b. Awakened from sleep by pain more than 3 times per week

c. Not usually awakened from sleep by pain

d. Restless sleep or early morning awakening with or without being able to return to sleep, both
unrelated to pain
19. Has your pain affected your intimate personal relationships?

a. No
 b. Yes
11. Mark your average level of stress in the last month:
At Home
0
10
At Work
0
10
10. Mark on this scale how hopeful you are:
0% (Not at All)
100% (A Large Amount)
Fig. 66.1, cont’d
Continued

1285
Chapter 66 Peripheral Nerve Injuries and the Brachial Plexus
WUP PLAS SEM PAIN QUE C NL (Rev 05/15)
20. Are you involved in any legal action regarding your physical complaint?
 a. No  b. Yes
21. Is this a Workers' Compensation case?
 a. No  b. Yes
22. Are you presently receiving or have you ever received psychiatric/psychological treatment?
 a. No  b. Presently receiving psychiatric treatment  c. Previous psychiatric treatment
23. Have you ever thought of suicide?
 a. No  b. Yes  c. Previous suicide attempts
24. Were you a victim of childhood trauma– emotional or physical?
 a. No  b. Yes  c. No comment
25. Are you a victim of emotional abuse?
 a. No  b. Yes  c. No comment
26. Are you a victim of physical abuse?
 a. No  b. Yes  c. No comment
27. Are you a victim of sexual abuse?
 a. No  b. Yes  c. No comment
28. Are you presently a victim of abuse?
 a. No  b. Yes  c. No comment
29. Are you currently: (Check all that apply)
Employed for wages
 No  Yes
On medical leave
 No  Yes
A homemaker
 No  Yes
Self-employed
 No  Yes
Student
 No  Yes
Retired
 No  Yes
Volunteer
 No  Yes
None of the above
 No  Yes
30. If you are still working, do you?

a. Work every day at the same pre-pain job.

b. Work every day but the job is not the same as the pre-pain job with reduced responsibility or physical
activity.

c. Work occasionally.
31. Are you able to do your household chores?

a. Do same level of household activities without discomfort.

b. Do same level of household chores with discomfort.

c. Do a reduced amount of household chores.

d. Most household chores are now performed by others.
32. What medications have you used in the past month?

a. No medications

b. List medications:______________________________________________________________________________
_______________________________________________________________________________________________
_______________________________________________________________________________________________
33. If you had three wishes for anything in the world, what would you wish for?
1._________________________________________________________________________________________________
2._________________________________________________________________________________________________
3._________________________________________________________________________________________________
From: Hendler N, Viernstein M, Gucer P, Long D: A preoperative screening test for chronic back pain patients. Psychosomatics 1979;20:801-808.
Mackinnon SE & Dellon AL: Surgery of the Peripheral Nerve, Thieme Medical Publishers, 1988
Melzack R: The McGill pain questionnaire: major properties and scoring methods. Pain 1975;1:277-299.
Modified by 1/5/2010
Fig. 66.1, cont’d

SECTION VIII THE HAND AND UPPER EXTREMITY
1286
A comprehensive understanding of the patient’s pain,
including qualitative nature, location, and severity can help
to distinguish its potential sources. Pain from a neuroma is
generally focal, brief and intermittent, sharp, and consistent
with pressure or contact, whereas nonneuromatous pain is
often described as diffuse and inconsistent or of varying
quality and duration. The surgeon should proceed cautiously
if the patient completes a body pain diagram that does not
follow an anatomical distribution or pattern or uses more
than four adjectives to describe the pain. In such cases, a re­
ferral for a formal and comprehensive psychological evalu­
ation should be considered. The type of adjectives selected
to describe pain may also indicate a significant nonneuro­
logic component, and thus any psychological component
must also be appropriately managed for a successful out­
come. However, in our experience malingerers are exceed­
ingly rare, and we always give all pain patients the benefit
of an open, curious mind and a detailed history and physi­
cal examination. Electrodiagnostic studies are rarely helpful.
A variety of patient factors can also affect the quality of
nerve regeneration and outcomes. Age is a significant factor
in recovery after nerve injury. Younger patients in general
recover faster and more fully even after severely disabling
injuries.9 The correlation of age has been demonstrated
­experimentally in different models of injury and repair. In
addition to the shorter distances required for nerve regener­
ation and target end-organ reinnervation, children also have
superior cortical plasticity, which facilitates their rehabilita­
tion and is likely to play a significant role in their functional
outcome.10,11 Smoking has also been correlated with delayed
functional recovery in experimental models of nerve injury,
and medical comorbidities including diabetes, hypothyroid­
ism, and peripheral vascular disease can also have a negative
impact12,13 (Video 66.1).
Timing
Peripheral nerve surgery is rarely an emergent or urgent
procedure, even after trauma. The only true emergencies
mainly involve acute nerve compression of a posttraumatic
or postoperative nature. Examples include acute carpal
tunnel syndrome after carpal dislocation or severely dis­
placed distal radial fracture, which may require operative
reduction, or after their surgical management secondary to
edema and/or hematoma. Otherwise, a sharp nerve tran­
section is certainly time-sensitive and may require early
operative intervention within a few days to permit a pri­
mary tension-free nerve repair before contraction of the
nerve ends and edema precludes their direct coaptation. If
there is no tension at the nerve repair site, better functional
outcome can generally be expected if a nerve graft can be
avoided, but the outcome also depends on the length of a
nerve graft, as discussed further in the section on techni­
cal factors. If there is an injury to small but critical motor
nerves such as branches of the facial nerve, acute or early
intervention within 72 hours will permit identification of
the distal nerve stumps by electrical stimulation with mus­
cle contraction. Beyond that time, the muscles are no lon­
ger responsive and identification of the distal nerve stump
may be much more difficult.
A nerve that has lost continuity from a crush injury, tor­
sion, avulsion, or a combination of these mechanisms on the
other hand will benefit from a delayed approach to opera­
tive management. It is important in such cases that the zone
of injury is determined, because traumatized and scarred
nerve may not regenerate well or may be more likely to re­
sult in a painful neuroma. We recommend that operative
intervention in such cases be delayed for at least 3 weeks,
by which time the zone of injury on the nerve will be more
clearly demarcated using a “bread loafing” technique, serial
sectioning that can more readily determine the appearance
and texture of the normal fascicular pattern of a healthy
nerve. An injured, scarred segment of nerve will feel more
stiff and harder than nerve outside of the zone of injury, and
the appropriate amount of nerve that should be resected
and reconstructed is more readily determined. Otherwise
residual scar tissue will block axonal regeneration even if
nerve continuity is restored, and the functional outcome will
be suboptimal.
In some cases, operative intervention may be required
more acutely because of other associated injuries such as a
vascular injury and/or a coverage issue and the surgeon is
hesitant to reoperate at a later time because of extensive
scarring or prohibitive risk to a vascular repair or recon­
struction. In such circumstances, the surgeon will need to
make an educated guess as to the zone of injury and should
consider a wider nerve resection than might otherwise
seem necessary, because the extent of intraneural scarring
may not yet be fully evident. This will help to ensure that
all injured nerve is resected and nerve graft reconstruction
is performed to nerve ends outside of the zone of injury
to optimize axonal regeneration. In these instances we as­
sume the proximal and distal extent of injury from the site
of transection is similar. We then have the anesthesiologist
“lighten” the patient’s anesthetic and use a low setting on
the nerve stimulator to stimulate the proximal nerve stump.
As we move proximally we assess an increase in the patient’s
heart rate as an indicator of healthy nerve and use this as
part of the decision-making process to determine how far
to resect proximally, then use the measurement distally.16
Surgical intervention that occurs inappropriately early
can also be detrimental. An electromyogram (EMG) obtained
too early after injury may not be useful, because it takes ap­
proximately 6 weeks for electrical evidence of nerve injury
to become fully evident. At 12 weeks, if an EMG shows the
presence of motor unit potentials, good functional recovery is
anticipated even though clinical evidence of muscle recovery
may not be evident for months. If reconstruction is performed

1287
Chapter 66 Peripheral Nerve Injuries and the Brachial Plexus
neuromuscular junction and motor end plates, and irre­
versible architectural changes of muscle tissue will begin.
If nerve reconstruction including a distal nerve transfer is
finally undertaken, it will often still be another 6 months or
more before the regenerating axons reach and reinnervate
the target muscle. If the referral is made 8 months or longer
after the injury, it may already be too late to recover target
muscles by surgical reconstruction. Therefore referrals are
best made early so surgery can be undertaken as early as
appropriate, such as 3 to 4 months after injury for brachial
plexus reconstruction.
Classification of Nerve Injury
A good understanding of the classification of nerve injury
will help to determine the best timing for surgical inter­
vention or whether it is even appropriate. Seddon’s and
Sunderland’s classifications14,15 are applied to nerve lesions
of all causes; they facilitate care by providing indications
for nonoperative management versus surgical intervention
and guide expectations for both spontaneous recovery and
recovery from reconstruction (Tables 66.1 and 66.2).
Seddon’s Classification
Seddon’s classification consists of three types of nerve in­
jury: neurapraxia, axonotmesis, and neurotmesis.11
Neurapraxia
A neurapraxia is the least severe injury and represents
a conduction block at a discrete segment of a nerve that
may be related to an ischemic insult or demyelination. The
nerve remains in continuity, and because there is no axo­
nal injury, there is no distal Wallerian degeneration, so no
axonal regeneration is required. On physical examination,
Tinel’s sign will not be present and grossly the nerve will
look normal in appearance, but the histologic appearance
may demonstrate a focal area of demyelination.
in such cases, muscle reinnervation and recovery will be
substantially delayed and the outcome will be less favorable
than expected with spontaneous recovery. However, if the
injured nerve has well-established probable distal compres­
sion points, surgical decompression should be considered and
will facilitate distal regeneration. Examples include median
or ulnar nerve injuries in the forearm or higher with release
of the carpal tunnel or Guyon canal at the wrist.
In many cases, patients are referred too late and nerve
reconstruction is no longer helpful. This is more common
when the distance required for nerve regeneration to reach
the target muscles is long, such as proximal lower and upper
extremity injuries, including brachial plexus injuries. Com­
monly these patients are followed by the referring physi­
cian with the expectation that spontaneous recovery will
be forthcoming, Typically it takes time for the realization
to occur that surgery may be required, and by the time the
patient is referred to and seen by the specialist, it may be
too late to reinnervate the target muscles. At approximately
one year of denervation, there will be deterioration of the
Table 66.1 Seddon’s and Sunderland’s
classifications: comparison of
prognosis and recovery
Seddon
Sunderland
Prognosis
Recovery
rate
Neurapraxia
I
Normal
Quick
Axonotmesis
II
III
IV
Good
Partial
−
Slow
Slow
−
Neurotmesis
V
VIa
+/−
−
+/−
aCombination of any of Sunderland degrees (I–V). Negative sign indicates
poor prognosis or no recovery; plus/minus sign indicates mixed progno­
sis or some recovery (some fascicles recover, some don’t).
Table 66.2 Histopathologic changes and Tinel signs related to degree of injury
Histopathologic changes
Tinel’s sign
Degree of injury
Myelin
Axon
Endoneurium
Perineurium
Epineurium
Present
Progresses
distally
I Neurapraxia
+/−
−
−
II Axonotmesis
+
+
+
+
III
+
+
+
+
+
IV
+
+
+
+
+
−
V
+
+
+
+
+
+
−
VI
Various fibers and fascicles demonstrate various pathologic changes
+
+/−

SECTION VIII THE HAND AND UPPER EXTREMITY
1288
neurotmesis. The third-degree injuries fall under the classi­
fication of axonotmesis but with more extensive injury. In
a third-degree injury, the Schwann’s cell basal lamina that
makes up the endoneurial sheath is violated, causing scar­
ring and fibrosis that impedes axonal regeneration. Conse­
quently, functional recovery is often incomplete because not
all of the end organs are fully reinnervated, and the loss of
the endoneural guide will also lead to some mismatching of
regenerating axons to their proper distal sheath pathways,
further downgrading functional restoration. The functional
outcome will also depend on the level of the nerve injury.
In a proximal nerve, motor and sensory axons are more
mixed topographically within a fascicular group and there is
more likely to be modality mismatching where motor axons
regenerate down sensory pathways or vice versa and rein­
nervate inappropriate end organs. Further distally there is
better fascicular grouping of motor and sensory axons,12 and
mismatching is more likely to occur with axons of the same
modality. Any deficits in end-organ recovery are therefore
more likely to result from incomplete nerve regeneration
related to scarring at the lesion and less from modality mis­
matching as well. In a fourth-degree injury, there is complete
disruption of axons and all connective tissue sheaths like a
neurotmesis, but the nerve physically remains in continu­
ity by scar tissue. There is no nerve regeneration because it
is completely blocked by scar tissue and therefore resection
and nerve graft reconstruction are required.
A seventh-degree injury has been termed by Mackin­
non13 and is a mixed injury pattern representing the exis­
tence of more than one or even all of Sunderland’s injury
degrees in a neuroma in continuity.16 The variability in the
extent of injury exists not only among the different fascicles
at a given level but also along the length of the nerve. The
technical dilemma lies in appropriately resecting and recon­
structing the fascicles with levels of injury that won’t regen­
erate (fourth degree and fifth degree) while leaving intact
those that will (first through third degrees). The identifica­
tion of the functional and sensory deficits is made clinically
preoperatively and coordinated with intraoperative assess­
ment after internal neurolysis and electrical stimulation to
identify the functioning components to avoid in the resec­
tion and minimize downgrading of any remaining function.
Thus the most appropriate timing for surgical manage­
ment depends entirely on the extent of the nerve injury
and the capacity for spontaneous recovery or not. If there
is certain or a good possibility of spontaneous recovery
­(Sunderlund’s first through third degrees), then observation
is ­continued until either the progression ceases or regen­
eration appears to be held up where there may be a Tinel’s
sign at a known area of entrapment, such as the carpal or
cubital tunnels, or the proximal fibular head. In such cases,
it is then reasonable to proceed with decompression at the
entrapment site in an elective manner.
If the anatomical progression of recovery stops with per­
sistent functional deficits, then some fourth and fifth degree
injury is present and surgical intervention is indicated. With
a known sixth-degree level of injury, surgical reconstruction
may be planned but will not be scheduled until a period of
Recovery requires reversal of the ischemic block or re­
myelination; once complete, the conduction block is re­
solved and the return of nerve function should be very quick.
The anticipated recovery is generally within 3 months, and
a full functional recovery is expected. Examples of neura­
praxia include tourniquet palsies, positional compression
palsy, or the early stages of compression in a nerve entrap­
ment syndrome.
Axonotmesis
An axonotmesis is the next Seddon injury level and repre­
sents axonal injury in which the epineurium, endoneurium,
and perineurium all remain intact. Because there is actual
axonal disruption, Wallerian degeneration will occur in the
distal nerve segment and axonal sprouting will be seen from
the proximal nerve stump. In these favorable axonotmetic
injuries, good to excellent recovery occurs because unin­
jured axons respond to the adjacent denervated neuromus­
cular end-plates with collateral sprouting. These are detected
by motor units at 12 weeks of injury in distal muscles, far too
distal to represent injured axonal regeneration from the level
of the injury. These early collateral motor units will “babysit”
the denervated muscles and provide a supportive environ­
ment as the slow regeneration occurs from the injured ax­
ons (nascent units). Spontaneous recovery is again expected,
because the intact sheaths will guide the regenerating axons
to their distal end-organ targets, but will occur slowly at the
classic rate of 1 to 1.5 mm/day or approximately 1 inch per
month. Because the connective tissue sheaths remain intact,
there is minimal to no scar tissue to impede the regenerat­
ing axons, whose progression can be followed clinically by
an advancing Tinel’s sign. There should be an orderly ana­
tomical progression of functional recovery from the proxi­
mal to distal motor and sensory branches. The restoration of
neurologic function is expected to be complete because the
injury is purely axonal and the Schwann’s cell basal lamina
that makes up the endoneurial sheath remains intact.
Neurotmesis
A neurotmesis is the most severe class of injury in Sed­
don’s classification and involves complete transection of a
nerve, including the axons and all of the connective tissue
sheaths. Surgical intervention with repair or reconstruc­
tion is required for proper nerve regeneration and reinner­
vation of target end organs. The rate of axonal regeneration
will follow the classic rate described previously, but scar
tissue at the repair or reconstruction sites will provide vari­
ability to the extent of nerve regeneration, reinnervation,
and functional recovery.
Sunderland’s Classification
Sunderland’s classification expands the more severe classes
of injury in Seddon’s classification.14 His first-degree injury
is equivalent to a neurapraxia, a second-degree injury is
an axonotmesis, and a fifth-degree injury is the same as a

1289
Chapter 66 Peripheral Nerve Injuries and the Brachial Plexus
may not be evident for up to 12 weeks after injury, and con­
sequently, EMG studies are not very helpful before that time
period. Reinnervation from axonal regeneration rather than
collateral sprouting of viable axons produces motor unit po­
tentials that contrast those from collateral sprouting. These
are known as nascent potentials and have short duration,
low voltage, and a more immature form. They may appear
up to 2 months before any clinical signs of muscle reinner­
vation or recovery.
As reinnervation progresses to more muscle fibers, the
potentials slowly increase in amplitude while the number of
polyphasic units shows a corresponding decrease, and fibril­
lations will also slowly resolve during the process.17
In summary, an EMG obtained before 6 weeks after
the injury will be able to distinguish a first-degree injury
or neurapraxia from more severe injuries (second through
fifth degree) by the absence of fibrillations in muscle distal
to the nerve injury and any preexisting nerve injury. How­
ever, it will not be able to differentiate lesions for which
spontaneous recovery is expected (second and third de­
gree) from those that have no capacity to recover (fourth
and fifth degree). A study obtained after 6 weeks from the
injury may be able to also show motor unit potentials and
nascent units, indicating that at least some recovery is forth­
coming. For most closed injuries, including brachial plexus
injuries, an observation period of approximately 3 months
is advocated (4 months for gunshot wounds), and surgery
is recommended if there is no evidence, electrical or other­
wise, of reinnervation by that time.
Electrodiagnostic studies may also be helpful in deter­
mining both whether a patient is an appropriate surgical
candidate and, for compression neuropathies, which pro­
cedures are most likely to be successful. Although the clini­
cal presentation and examination are the most important in
evaluating a patient with a possible nerve entrapment syn­
drome, the surgeon should proceed cautiously if the elec­
trodiagnostic studies are normal. Neurologic changes and
pain in an extremity may also come from a more proximal
source, such as spinal root compression associated with de­
generative disease or trauma. In such cases, peripheral nerve
decompression will not address the primary source of the
symptoms and may not be helpful, and it subjects the pa­
tient to unnecessary surgery. Nerve compression may also
occur at more than one level, such as median nerve com­
pression at both the proximal forearm and the carpal tunnel.
Both sites will need to be addressed to provide the patient
with an optimal chance of a successful outcome.
Surgical Considerations
Exposure
Wide exposure with good visualization is necessary for
successful nerve surgery. For nerve decompression pro­
cedures, a small incision with limited exposure may not
provide adequate visualization at the most proximal and
distal ends of the dissection and may lead to inadequate
decompression at either end where a fascial edge or a sharp
waiting is recommended to provide time for the less ­severely
injured nerve components to show evidence of recovery.
Such evidence may be appreciated by clinical examination
with visible or palpable muscle contraction, which may still
be very early and subtle, or may not be clinically evident but
demonstrated by the presence of motor unit potentials on
an EMG study.
Examples of such cases include brachial plexus injuries
and gunshot wounds in proximity to major nerves. A standard
management protocol will include a period of observation
of approximately 3 and 4 months, respectively, which may
vary somewhat at different institutions, followed by surgery
to reconstruct the components that have not shown any evi­
dence of recovery at that point. In these cases, recovery of the
components with lesser degrees of injury will still be ongoing,
and surgery may even be held off indefinitely as long as the
critical surgically reconstructable functions are improving.
Some functions such as hand function in brachial plexus
injuries are not amenable to reconstructive nerve surgery
because their distal level precludes the possibility of muscle
reinnervation before the development of permanent struc­
tural changes of the motor end-plates and muscle architec­
ture. Reconstruction is still possible with nerve transfers
or functional muscle transfers but will be of lower priority
than more proximal functions, such as elbow flexion and
shoulder abduction, that are recoverable with nerve recon­
struction.
Electrodiagnostic Studies
Electrodiagnostic studies are invaluable to the assessment
of the degree of nerve injury and the recovery of muscle
function. Proper interpretation requires a basic under­
standing of the terminology and its clinical correlation.
Conduction velocity and distal latency reflects myelin­
ation with a demyelinating lesion, such as a neurapraxia
causing a decrease in conduction velocity and therefore an
­increase in distal latency.
Waveform amplitude is an indicator of the number of
axons functioning, with a decrease representing greater
loss of axons. After axonal injury, muscle distal to the level
of the lesion may still stimulate for up to 7 to 10 days but
thereafter will no longer be responsive. Muscle fibrillations
on a needle EMG, however, may not be demonstrated for
­approximately 3 to 6 weeks after injury and will be present
as long as there is some degree of denervation. In a muscle
that has had a completely denervating injury and no rein­
nervation has occurred, fibrillations will generally disappear
after ­approximately 1 year. Once this has occurred, that mus­
cle is no longer recoverable by surgical means or otherwise.
In a partially denervated muscle, however, fibrillations
may still be seen for years after injury and may indicate the
ability of the muscle to respond to further reinnervation. In
partial denervation injuries, muscle reinnervation will first
begin with collateral axonal sprouting from the intact viable
axons to the denervated muscle fibers, causing the existing
motor unit potentials to become polyphasic and of longer
duration, but the amplitude may not change. These findings

SECTION VIII THE HAND AND UPPER EXTREMITY
1290
force a primary repair. For example, the elbow should not
be flexed to allow a primary repair of a lacerated ulnar or
median nerve. In such cases, the elbow should be extended
and nerve grafts used such that the joint can be moved
through its full range of motion while the nerve coapta­
tions remain intact and loose. As in nerve repairs, it is criti­
cal that motor and sensory fascicles are properly aligned
to minimize modality mismatch, which will downgrade
the functional outcome. Thus when reconstructing a gap
with nerve grafts, it is important that the nerve stumps are
anatomically positioned and rotated, and that nerve grafts
done in a cabled fashion are matched as closely as possible
to the corresponding topographical regions of the proximal
and distal nerve stumps. Cabled nerve grafts should there­
fore also be in linear alignment with each other without
any twisting or torsion, which might contribute to fascicu­
lar mismatch (Fig. 66.3).
change in the direction or angle of the nerve course may
be present. When a patient is referred to us with persis­
tent symptoms after an initial decompression procedure
with a short scar, such as after ulnar nerve transposition,
we usually initially suspect ongoing compression at either
the proximal or distal end for the reasons previously men­
tioned. Although safe in experienced hands, we also do
not advocate the endoscopic approach to carpal tunnel re­
lease. Visualization is certainly more limited, and although
the incidence of complications has not been shown to be
any higher than the open approach, they do include more
severe complications such as complete transection of the
median or ulnar nerve.18 With limited exposure and visual­
ization, longitudinal structures such as tendons and nerves
may appear similar, but a wider exposure will help to con­
firm their course and true identity.
Nerve Repair
Technical factors also play a large role in affecting out­
come, especially in the management of proximal mixed
nerve injuries. The pros and cons of epineurial versus
grouped fascicular repairs are generally understood, but
the topographical anatomy of larger mixed nerves is still
underappreciated. It is important that the two nerve ends
are in their most anatomically accurate position and rota­
tion to avoid a mismatch of sensory with motor fascicles
and vice versa. Any degree of mismatch will downgrade
the anticipated anatomical outcome, but a total mismatch
may lead to absolutely no muscle reinnervation, whereas
a partial mismatch may lead to abnormal target muscle
reinnervation and complicate the rehabilitation. Therefore
we feel that an epineurial repair is better than a grouped
fascicular repair in most cases, because rarely is the proper
topographical alignment of the nerve stumps perfectly
clear without a doubt. Only in such circumstances should
a grouped fascicular repair be used.
Anatomical clues can be used to verify that the two
nerve ends are in their most anatomically accurate position
before a repair or reconstruction is performed. The position
of vasa nervorum running longitudinally can be used to line
up the two nerve ends correctly (Fig. 66.2). Also, the config­
uration of the transected nerve ends may provide clues as to
how the ends match up the best. For example, an obliquely
oriented nerve laceration will be more accurately lined up
than a completely transverse nerve laceration, because the
nerve stump configurations will tend to match up better as
they are brought together. The fascicular grouping pattern at
each of the nerve ends should also be noted and can provide
further clues if the patterns can be recognized and matched
to each other. In general, all of these techniques should be
used together when coapting nerve ends to ensure that re­
generating axons reach their appropriate end organs.
Nerve Grafts
There should be no tension on the nerve coaptation, and
flexed positioning compensation should not be relied on to
Fig. 66.2 Exposure of the median nerve in the forearm demonstrat­
ing longitudinal epineurial blood vessels (vasa nervorum), which can
facilitate anatomical positioning of nerve stumps when performing
a primary repair after transection.
Fig. 66.3 Cabled nerve graft reconstruction of the median nerve in
the distal forearm demonstrating consistent linear alignment of the
grafts to optimize fascicular matching.

1291
Chapter 66 Peripheral Nerve Injuries and the Brachial Plexus
education and cortical remapping and provide the best po­
tential outcome.
A double fascicular transfer of a flexor carpi ulnaris fas­
cicle of the ulnar nerve and a flexor carpi radialis (FCR) fas­
cicle of the median nerve to reinnervate the elbow flexors
is ideal, because the rehabilitation is intuitive and the do­
nor nerve fascicles are extremely close to the target muscles
to minimize the denervation time. The medial pectoral and
thoracodorsal nerves are also excellent donors but are far­
ther away from the elbow flexors. The distal accessory to the
suprascapular nerve and triceps branch to the axillary nerve
are the preferred transfers to restore shoulder function and
make up the standard double nerve transfer combination.
We have also used nerve transfers at the level of the fore­
arm for high ulnar, median, or radial nerve injuries. For exam­
ple, in a patient with a radial nerve palsy, the FCR and flexor
digitorum superficialis (FDS) branches of the median nerve
can be transferred in the proximal forearm to the posterior
interosseous nerve (PIN) and extensor carpi radialis brevis
(ECRB) branches of the radial nerve, respectively, with good
results and the potential even for independent finger motion.
On the other hand, the ECRB and supinator branches of
the radial nerve make good donor nerves for transfer to the
pronator and anterior interosseous nerve (AIN) branches of
the median nerve, respectively, for high median nerve inju­
ries. Such transfers provide an additional option other than
standard tendon transfers in an appropriately selected pa­
tient. Both nerve and tendon transfers have advantages and
disadvantages, and the best choice should be an informed
decision made together by the surgeon and the patient.
Managing Unfavorable Results
and Complications in Nerve
Surgery
Neuromas
The development of a neuroma is a normal physiological re­
sponse to a nerve injury or lesion and represents the nerve’s
attempt to repair itself and restore its end-organ connec­
tivity. When a nerve has been transected or its continuity
otherwise disrupted, the distal end undergoes Wallerian
degeneration while the proximal stump forms numerous
regenerating sprouts in search of distal targets to reestablish
contact. The result is a firm growth or swelling at the end of
the nerve consisting of scar tissue and nerve endings that
are very sensitive to contact or percussion, or Tinel’s sign. If
the nerve continuity is restored and distal connections are
reestablished, then regeneration can ensue, target end or­
gans are reinnervated, and the neuroma-associated pain im­
proves or resolves. If not, then the neuroma will persist and
the patient remains symptomatic with pain and disability.
Any nerve injury, whether accidental (as in trauma) or
intentional (as in the harvest of a nerve graft) has the po­
tential to form a problematic neuroma. The experimental
The use of nerve substitutes to reconstruct a gap has
been shown to be effective in certain circumstances. Accord­
ing to preclinical and clinical studies, commercially avail­
able, absorbable nerve conduits support regeneration across
a nerve gap up to 30 mm in length, beyond which no mean­
ingful nerve regeneration occurs.19,20 Therefore, if necessary,
conduits should only be considered for small nerve gaps
(shorter than 30 mm) in noncritical sensory nerves. Acellu­
lar nerve allografts (ANAs) have become increasingly popu­
lar as an off-the-shelf alternative to nerve autografts with
regeneration superior to commercially available “empty”
conduits.19,21 They work well for short gaps (30 mm or
shorter) in small diameter (2 mm or smaller) sensory nerves.
However, the results have been less satisfactory for long gaps
in nerves of larger size, and their “critical gap length” has
not yet been defined. Nevertheless, ANAs are available in a
number of sizes and lengths, and the efficacy for most of
these has not yet been proven. Recent literature is suggest­
ing some efficacy for mixed and even motor nerves, but this
still remains very controversial. The gold standard remains
the nerve autograft. Currently we do not recommend using
ANAs to reconstruct a long gap in medium- to large-diameter
nerves, especially for critical function.
Nerve Transfers
Nerve transfers have conventionally been used mainly in
the management of brachial plexus injuries. However, this
technique has recently seen more widespread application
to other types of proximal nerve injuries with promising
results and is particularly advantageous in high proxi­
mal lesions where there is a long regeneration distance
to reach the target muscles or when the zone of injury is
large and long nerve grafts are otherwise required for re­
construction. A distal nerve transfer will reduce the dis­
tance and time required for regeneration, essentially con­
verting a high nerve injury to a low injury. In most cases,
depending on the availability of donor motor nerves, a
direct end-to-end nerve coaptation is possible, but oc­
casionally a short nerve graft may be required. Another
advantage is that the dissection is typically outside the
zone of injury in natural anatomical planes without the
extensive scarring that is typically encountered within
the zone of injury. This is especially advantageous in cases
in which the initial trauma also included a vascular injury
that required surgical repair and the risk of reinjuring the
vessels while dissecting in the hostile scarred field may
otherwise seem prohibitive.
Identification and assessment of available donor motor
nerves for transfer is done preoperatively by clinical func­
tional examination and intraoperatively by electrical stim­
ulation, typically with a handheld, battery-operated nerve
stimulator. An expendable, uninjured “pure” motor nerve
in proximity to the target muscle is the ideal choice, retain­
ing the maximal number of motor axons possible. If more
than one donor motor nerve is available, then the one that
supplies a muscle whose action is most synergistic to that
of the target muscle will facilitate the process of motor re­

SECTION VIII THE HAND AND UPPER EXTREMITY
1292
Chronic pain may best be managed by a pain clinic, because
pharmacologic treatment generally includes multiple classes
of medications including narcotics, anxiolytics, and antiep­
ileptics in varying combinations over the long term, and
therefore there is a high potential for addiction and abuse.
If surgical intervention is being considered, an anesthetic
nerve block will provide diagnostic information regarding
the specific nerves involved and the potential response to
surgery. If no improvement is seen after one or more nerve
blocks of the most suspected nerve injury, then surgical
management of that nerve is unlikely to improve the pain
and in fact may exacerbate the symptoms further. A block
is also helpful in determining whether more than one nerve
may be involved as the source of pain. For example, pain in
the distribution of the radial sensory nerve has been notori­
ously difficult to manage because of the overlap of the ter­
ritory with the lateral antebrachial cutaneous nerve. If both
nerves are contributing sources to the pain, then both will
need to be addressed surgically for a successful outcome.
The severity of the pain may also provide an indication of
the likelihood of improvement with surgical intervention. If
the patient is able and willing to allow palpation of the pain­
ful site freely and repeatedly, then nerve grafting surgery is
unlikely to be helpful and a decompression of the brachiora­
dialis tendon should be considered. If surgical management
has already been undertaken and has not been successful,
additional surgical attempts should be resisted, because they
are even less likely to provide improvement and the patient
should be referred to a pain management clinic.
Rehabilitation
As in hand surgery, hand therapy after nerve surgery is
critical to the optimal recovery of the patient. It assists with
the painful sequelae of sensory nerve lesions and is essen­
tial for the motor rehabilitation after nerve transfer surgery
in the same manner as it is after tendon transfers. A patient
undergoing nerve or tendon transfer surgery who is not of­
fered postoperative therapy will have an inferior result be­
cause they do not know how to “activate” the target muscle
properly, even though the muscle may be reinnervated.
As such, the crucial role of cortical changes and plasticity
that occur after nerve injury and denervation, and progress
through the reinnervation process, must be recognized to
optimize patient outcome, especially after nerve transfer
surgery. The source of reinnervation of the target muscle
after transfer is different, so the native motor pathways and
cortical maps previously established are no longer relevant.
New motor patterns and cortical remapping will need to
be developed to restore maximum function of the extrem­
ity. Previous work has shown that changes occur in regional
brain activity and cortical mapping by transcranial imaging
after nerve transfer surgery.23–25 Rehabilitation after nerve
injury and/or surgery can be reviewed in two phases.
The early phase applies to any patient after a nerve re­
pair or reconstruction and after hand and extremity inju­
ries in general. The main priority is to maintain or recover
range of motion limited by pain or edema or after a period of
literature consists of numerous technical methods that have
been shown to minimize neuroma formation to varying de­
grees and thus limit the probability of developing a painful
neuroma.22 Such measures include resection of the neuroma
with crushing, cauterization, or ligation of the proximal
nerve stump, and then proximal transposition of the nerve
end deep into bone or innervated muscle, where it can be
well padded with soft tissue, and away from the surgical site,
where significant scar formation is anticipated.
Burying the proximal nerve stump in innervated muscle
will help to inhibit axonal regeneration and thus the forma­
tion of a new neuroma. The muscle chosen should be of good
size, deep and with as little movement as possible. If the
muscle used is small and has significant excursion, the out­
come is unlikely to be successful. However, placement of the
proximal end superficially and near denervated skin and scar
will have the opposite effect and encourage regeneration
and neuroma formation. These measures should therefore
be used whenever possible on the proximal nerve end when
a nerve graft is harvested to minimize donor site morbidity.
It is also important that the nerve end is not subject to any
tension or traction, and so we do not advocate suturing or
other means of attempting to secure the nerve stump in its
transposed position.
Our current strategy for surgical management of a neu­
roma is to excise the neuroma and follow the involved nerve
proximally as far as reasonably possible. We then crush the
nerve at that proximal level to make a second-degree axo­
notmetic injury to move the regeneration front as proximal
as possible and “reset” the central neuropathic changes. At
the distal end of the nerve we add an acellular nerve al­
lograft or Seprafilm, because both “dwindle” nerve regen­
eration.
If a symptomatic neuroma has formed, the most reli­
able method of management is to reconstruct the nerve and
restore its continuity either primarily if possible or more
commonly with a nerve autograft (or for short gaps a pro­
cessed allograft). This not only helps to control or alleviate
the proximal painful neuroma but also helps to restore in­
nervation to the distal sensory territory. Reconstruction will
also help to manage any component of pain possibly coming
from the distal nerve stump, which has been suggested in
experimental models to be a possible contributing factor to
neuroma pain by providing a potential source of hyperalge­
sia and allodynia in the distal sensory territory.1
In the case of harvesting a long nerve graft such as the
full length of the medial antebrachial cutaneous (MABC) or
sural nerves, it may not be practical or possible to recon­
struct the nerve. In such common circumstances, the proxi­
mal stump should be transposed and buried as described
earlier, and the distal stump can be transferred in an end-
to-side fashion to a nearby intact sensory nerve if available.
This will induce some sprouting from the side of the viable
donor nerve to provide a limited degree of reinnervation to
the distal sensory territory and help to minimize the donor
site morbidity.
A patient with neuroma pain should be initially man­
aged with pharmacologic and desensitization therapy.

1293
Chapter 66 Peripheral Nerve Injuries and the Brachial Plexus
motor nerve to an antagonistic muscle can be used, but re­
training will require more time and effort, and in the end the
functional use may not be as good, much like using an an­
tagonistic donor for a tendon or muscle transfer. If a patient
is not able to learn how to activate the reinnervated muscle
consistently, he or she will not be able to strengthen it sat­
isfactorily and ultimately use it efficiently.26
While in training to strengthen a reinnervated muscle,
it is harder to activate muscle contraction against gravity
when fully lengthened, such as a fully extended elbow when
retraining for elbow flexion. Therefore the patient begins
with place-and-hold exercises initially at midrange with the
elbow flexed approximately 90 degrees, then progressing
to different degrees of elbow flexion with increasing exten­
sion as the starting point or exercises in gravity-eliminated
postures.27 Only after the patient is able to perform the full
range of motion against gravity are resisted exercises then
begun for further strengthening. With further progress the
patient is encouraged to start learning how to use both ex­
tremities again for activities of daily living, work, and rec­
reation. Return to work is certainly possible depending on
the nature and type of work and will be facilitated by the
use of vocational rehabilitation and the early integration of
long-term goals in the recovery process.28
Conclusion
The successful management of peripheral nerve lesions
requires a thorough understanding of the pathophysiol­
ogy and classification of nerve injury, axonal regeneration,
and the capacity for spontaneous recovery. The timing of
surgery is critical, because the recovery of the neuromus­
cular unit is time-sensitive and surgical intervention ei­
ther too early or too late can have adverse effects on the
final outcome. Appropriate patient selection can also be
challenging, because the diagnosis may not be completely
clear, especially for patients with compression neuropathy
or painful sequelae from trauma or surgery. Patients with
chronic pain are the most challenging to manage. Surgeons
wanting to treat this patient population need to be pre­
pared to devote a significant amount of time to evaluate
and manage these patients. A successful outcome is pos­
sible in these patients. Most patients with nerve problems
that require surgical intervention can be managed success­
fully with the appropriate knowledge, training, and multi­
disciplinary care and are grateful for the sensory and func­
tional improvement that surgery can provide.
immobilization. Early mobilization will also limit the effect
of scar tissue formation and adherence of nerve to surround­
ing soft tissues, and therefore the patient should be encour­
aged to begin moving as early as possible. If the principles
of nerve repair and grafting are adhered to strictly, namely
tension-free nerve coaptations throughout the full range of
joint motion, then theoretically no immobilization should
be necessary. However, patients will often benefit from a
short period of immobilization immediately postoperatively
to minimize pain, discomfort, and edema, but then should
be encouraged to begin moving as soon as it is tolerated.
Desensitization therapy and exercises may also be help­
ful to patients with significant postoperative allodynia and
for those whose surgery was performed for pain. Once good
passive mobility has been achieved, home exercises may be
sufficient, but the patient should be followed regularly for
muscle tightness and imbalance and for initial evidence of
muscle reinnervation.
After brachial plexus injury, an arm sling should be con­
tinued to support the arm and alleviate the glenohumeral
subluxation as much as possible. This may also improve ex­
tremity edema if present by decreasing the dependent po­
sitioning of the forearm and hand. When reinnervation of
the supraspinatus or deltoid muscles is sufficient to resolve
the glenohumeral subluxation, the arm sling can be discon­
tinued if preferred.
The late phase of rehabilitation begins once there is evi­
dence of target muscle reinnervation. The priorities of this
phase are motor reeducation and strengthening. Recovery of
muscle function will begin first with a subtle twitch of the
muscle, which may even go unnoticed until the contraction
becomes strong enough to verify repeatedly. Because muscle
strength will initially be very weak, exercises are begun in
gravity-assisted or gravity-eliminated positions. In the case
of nerve transfers, the patient will learn how to correctly and
sufficiently activate the reinnervated muscle. The patient
has been “rewired,” so activation of the reinnervated target
muscle will not be accomplished by thinking of the intended
action intuitively but will require attempted activation of the
donor muscle action. For example, transfer of a flexor carpi
radialis fascicle of the median nerve for elbow flexion will
require wrist flexion to activate the elbow flexors. Therefore
a donor motor nerve that allows synergistic movement to
activate the target muscle will be easier to retrain and use
in a timely and coordinated manner than a donor nerve that
innervated a muscle whose action is antagonistic to that of
the target muscle. If no other donors are available, a donor
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21. Karabekmez FE, Duymaz A, Moran SL. Early clinical out­
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22. Colbert SH. Painful sequelae of peripheral nerve injuries.
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Special Commentary: Brachial Plexus Birth Injury by John A.I. Grossman,
Andrew E. Price, Harvey Chim, Herbert Valencia, and Leslie Agatha Grossman
Brachial plexus birth injuries are a unique subset of
peripheral nerve injuries. Over the last 30 years there
have been significant advances in both the early micro­
neurosurgical treatment of primary injuries and later
reconstruction of secondary musculoskeletal deformi­
ties of the injured limb. However, little attention has
been given to the potential complications encountered
at each stage of the treatment and strategies to avoid
or manage an unfavorable result.1-4 This commentary
will consider this issue at each of the different phases
of treatment from the perspective of the reconstructive
surgeon.
Initial Presentation and Evaluation
These infants are often seen as early as 1 to 3 months
of age, usually by the treating pediatric neurologist and
sometimes by a brachial plexus surgeon. In all cases it
is important to confirm that there are no other pedi­
atric medical problems and to rule out any associated

1295
Chapter 66 Peripheral Nerve Injuries and the Brachial Plexus
congenital lesions. The careful initial physical examina­
tion should focus on two areas:
1. The extent of the injury ( i.e., C5–6 with or without
C7 versus a global palsy)
2. The condition of the involved shoulder and elbow
It is not uncommon in upper and middle plexus lesions
to find early evidence of tightness to passive external
rotation or even the presence of an internal rotation
contracture of the shoulder combined with difficulties
in elevation. Rarely, traumatic shoulder or elbow dis­
locations can occur and are often missed. It is impor­
tant that this be addressed immediately in conjunction
with the treating therapist, preferably using the Van­
couver supination–external rotation splint (Sup-ER)
(Fig. 66D.1) for sleeping and gentle stretching. In our
practice, we have a low threshold for proceeding with
an early examination of the glenohumeral joint under
sedation and placement of botulinum toxin into the in­
ternal rotators and adductors of the shoulder, including
the pectoralis major, latissimus dorsi and teres major,
and subscapularis. This procedure must be performed
using general anesthesia with a careful manipula­
tion of the glenohumeral joint (Fig. 66D.2). To ensure
maximum success from the botulinum toxin injection,
it should be performed using a Teflon-coated needle
and with direct muscle stimulation (Fig. 66D.3). Our
research has shown that an experienced surgeon will
miss the target muscle in more than 20% of cases not
using this method.
Occasionally an infant younger than 6 months of
age presents with a very tight internal rotation con­
tracture, and in these cases we proceed with ultraso­
nography or preferably magnetic resonance imaging,
an examination under sedation, and, if we are able to
obtain passive reduction of the posteriorly subluxated
glenohumeral joint with stability, we place botuli­
num toxin and a shoulder spica cast for 3 weeks. It is
critical to obtain full passive external rotation of the
shoulder. If this is not possible, a subscapularis slide is
performed. Often, plexus repair with nerve transfers
and grafts is performed simultaneously depending on
the clinical situation. This complicated subject is not
described here.
Presurgical Considerations for Early
Nerve Surgery
Our experience in operating on over 400 cases of
brachial plexus birth injury for primary nerve recon­
struction has suggested that a careful preoperative
Fig. 66D.1 Vancouver supination–external rotation splint
(Sup-ER)
Fig. 66D.2 Examination of the glenohumeral joint using gen­
eral anesthesia.
a
b

SECTION VIII THE HAND AND UPPER EXTREMITY
1296
evaluation can greatly aid in the avoidance of certain
surgical complications.3,5 This includes both a detailed
history of recent respiratory illness and family respira­
tory illness as well as a careful physical examination
by the pediatric anesthesiologist. In our report of 100
consecutive cases with a focus on perioperative com­
plications, we found that the most common causes of
prolonged hospitalization were, in fact, intraoperative
or postoperative respiratory issues. These present the
most considerable risk. It is also important to deter­
mine the situation preoperatively with regard to the
phrenic nerve using ultrasonography.
We believe that every case requires high-resolution
magnetic resonance imaging (MRI) of the cervical spine,
supraclavicular plexus, and shoulder. The information
provided greatly aids in intraoperative decision-making
both with regard to nerve repair and shoulder reduc­
tion, as well.
Intraoperative Complications
Careful microsurgical dissection and meticulous hemo­
stasis are key to avoiding an unfavorable intraoperative
event. Initial dissection must first identify the phrenic
nerve, because it needs to be mobilized carefully and
protected throughout the procedure. We do not pro­
ceed further in the dissection or reconstruction before
a careful and precise identification of the phrenic nerve
as confirmed by intraoperative direct stimulation (Fig.
66D.4). Fig. 66D.5 shows a chest radiograph of a patient
with phrenic nerve palsy.
Second, in regard to neurolysis, neuroma resection,
nerve grafting, or nerve transfer, it is important, intra­
operatively, to carefully evaluate the neuroma before
any resection. It has become our practice to carefully
determine intraoperative conduction after completion
of microsurgical neurolysis and to correlate this with
the preoperative examination and other available infor­
mation before simply resecting all damaged nerve, be­
cause there may be an incontinuity lesion that does not
require complete neuroma resection. Such lesions are
often candidates for “bypass grafting” with proximal or
distal end-to-side repair (Video 66D.1). It is important
to recognize that the natural history of brachial plexus
birth palsy includes, except in the most severe injuries,
functional recovery of elbow flexion. Thus all efforts
are made to eliminate iatrogenic loss of this movement.
The reconstruction of functional elbow flexion in this
population is difficult and often not successful. We have
observed lack of recovery of elbow flexion in less than
0.5 to 1% of more than 400 operated cases for primary
repair. Careful evaluation of the donor spinal nerves is
critical in achieving the best possible result from plexus
reconstruction using sural nerve grafting. The spinal
nerves must be carefully mobilized proximally into
healthy-appearing nerve, and this needs to be confirmed
Fig. 66D.3 Botulinum toxin injection into the internal rotators
and adductors of the shoulder.
Fig. 66D.4 Intraoperative stimulation of the phrenic nerve.
Fig. 66D.5 Chest radiograph showing phrenic nerve palsy.

1297
Chapter 66 Peripheral Nerve Injuries and the Brachial Plexus
with intraoperative histopathology (Fig. 66D.6). The in­
traoperative histopathology is correlated with the pre­
operative MRI findings and intraoperative motor and
sensory evoked potentials. It is important to appreciate
that the presence of a pseudomeningocele is often not
associated with a nerve avulsion, and this must always
be taken into consideration in clinical decision-making.
Only when all of this information is available should a
particular spinal nerve be used as the donor for nerve
grafting. Obviously failure to have an adequate proximal
stump is a preventable cause of surgical failure.
Other significant intraoperative complications re­
ported by Clarke and colleagues include chylothorax and
pneumothorax. We have not encountered this particu­
lar intraoperative complication. We have had a single
case of persistent leakage of lymphatic fluid intraoper­
atively. This requires a tedious dissection to locate the
transected lymph vessel and ligate and cauterize it.
Early Postoperative Complications
Early postoperative complications can usually be
avoided. The procedures vary in length from 6 to 10
hours. It is important that an experienced anesthesiol­
ogist is caring for the child during this period. We have
found that using continuous narcotic infusion is the best
anesthesia technique, not only because it seems to allow
for the most accurate intraoperative neurophysiology,
but also because it provides excellent early postopera­
tive analgesia. Fluid overload must be avoided and me­
ticulous attention to the endotracheal tube and airway
must be emphasized. Careful attention to the airway
postoperatively is critical. We have not experienced
the need for reintubation and believe that this must be
avoided, because it would certainly have a high inci­
dence of disruption of any nerve repairs that have been
performed. 
Postoperative immobilization with a cast
and collar can lead to both pressure lesions and vascular
compromise should there be an excessively tight cast or
swelling. We monitor the extremity using a pulse oxim­
eter for the 48 hours that the child generally remains in
the hospital. Great care and attention must be given as
well to the legs when there has been sural nerve grafting.
The potential for vascular compromise from tight dress­
ings exists and needs to be carefully monitored as well
(Fig. 66D.7).
Even in the best, most experienced hands less-than-
desirable outcomes will occur. Parents must be advised
that immediately postoperatively, there can be a down­
grade in terms of active motion once the cast is removed
and understand the possibility of a less-than-desirable
outcome.
Fig. 66D.6 Intraoperative histology and corresponding electromyogram showing healthy nerve axons.

SECTION VIII THE HAND AND UPPER EXTREMITY
1298
Complications with Secondary
Musculoskeletal Procedures
Shoulder
Surgical procedures for reconstruction of a shoul­
der deformity after a brachial plexus birth injury are
certainly the most common secondary operations
performed after age 2 or 3 years.6,7 These procedures
usually consist of contracture release combined with a
muscle transfer. In some cases in older children with
glenohumeral incongruity, a rotational osteotomy of
the humerus is indicated. Each of these procedures has
associated complications that can either limit the result
or actually increase the deformity (Fig. 66D.8).
Contracture release initially involves the subscapu­
laris muscle. Our preferred technique is the subscapu­
laris slide. We have specifically avoided anterior release,
either open or arthroscopically, because of the risk of
loss of subscapularis function. This is extremely difficult
to correct. If a full release is not obtained, the pectoralis
major tendon and coracoid are addressed. Failure to ob­
tain full passive shoulder mobility intraoperatively will
lead to an unsatisfactory result.
Muscle transfer surgery requires a reduced gleno­
humeral joint. In children younger than 4 years, there is
some potential for the glenoid to recover normal version
and configuration. If there is significant glenoid deformity
or retroversion, this needs to be addressed, or redislo­
cation or instability will result. After the age of 4 years,
without a congruent, reduced joint, an isolated muscle
transfer is contraindicated, and rotational osteotomy is
indicated. Other complications leading to an unfavorable
result in muscle transfer surgery can result either from
injuring the neurovascular pedicles to the latissimus dorsi
or teres major muscles during mobilization or contracture
release. We have also encountered cases resulting from
improper insertion of the transferred muscles such that
they either provide less-than-adequate active motion or
no change whatsoever in the range of motion. Complica­
tions to be avoided with an osteotomy of the humerus are
inadequate or excessive rotation. Excessive rotation has
been found to be considerably more problematic than an
underestimation of the amount.
Elbow
Operative reconstruction of the elbow flexion con­
tracture associated with brachial plexus birth inju­
ries is difficult. Often combined bony and soft tissue
procedures are needed with front and back incisions.
Excessive stretch in a postoperative cast can result in
neurovascular injury. Excessive soft tissue release, es­
pecially of the biceps tendon, can result in loss of elbow
supination and flexion power.
Wrist and Hand
The most common wrist and hand procedure is a ten­
don transfer to restore active or static wrist extension.8
Fig. 66D.7 Soft tissue necrosis from a tight cast.
Fig. 66D.8 Internal rotation contracture of the glenohumeral
joint.

1299
Chapter 66 Peripheral Nerve Injuries and the Brachial Plexus
Other classic tendon transfers and stabilization proce­
dures for the wrist and hand also have a unique role in
reconstructive surgery to maximize the form and func­
tion of the injured limb in these children.9 Especially in
the global palsy cases, it is critical to remember that the
donor tendon in a transfer is from the outset weakened
and thus may not actually be able to provide the nec­
essary power. In our experience with tendon transfers
for wrist extension in this population, all of the failures
were in global palsy cases and all of these patients had
a similar less favorable outcome from shoulder recon­
struction as well.
Conclusion
Prevention of complications begins at an early stage, at
the time of initial presentation and evaluation. It is at
this time that the stage is set for the future direction of
thinking and planning. At the very least, further surgi­
cal treatment should avoid downgrading existing func­
tion, avoid injury to the phrenic nerve, and avoid respi­
ratory complications. Reintubation of the airway after
brachial plexus repair may lead to disruption of the
delicate repairs. Careful intraoperative monitoring dur­
ing these lengthy procedures is necessary to prevent
fluid overload and minimize respiratory complications.
Potential complications may also occur with ill-advised
or ill-performed late reconstructive surgeries for ten­
don transfers, contracture releases of the shoulder and
elbow, and corrective osteotomies.
References
1. Blaauw G. Discussion: complications of microsurgi­
cal reconstruction of obstetrical brachial plexus palsy.
Plast Reconstr Surg 2003;111:1389–1390
2. Grossman JAI, Price AE, Tidwell MA, Ramos LE, Alfonso
I, Yaylali I. Outcome after later combined brachial plex­
us and shoulder surgery after birth trauma. J Bone Joint
Surg Br 2003;85(8):1166–1168
3. Grossman JAI, Price AE, Sadeghi P. Perioperative com­
plications associated with brachial plexus repair in in­
fants. J Hand Surg [Br] 2003;28(3):274–275
4. La Scala GC, Rice SB, Clarke HM. Complications of mi­
crosurgical reconstruction of obstetrical brachial plex­
us palsy. Plast Reconstr Surg 2003;111(4):1383–1388,
discussion 1389–1390
5. Ruchelsman DE, Ramos LE, Alfonso I, Price AE, Grossman
A, Grossman JAI. Outcome following spinal accessory to
suprascapular nerve transfer in infants with brachial
plexus birth injuries. Hand (NY) 2010;5(2):190-194
6. Grossman JA, DiTaranto P, Yaylali I, Alfonso I, Ramos LE,
Price AE. Shoulder function following late neurolysis
and bypass grafting for upper brachial plexus birth in­
juries. J Hand Surg [Br] 2004;29(4):356–358
7. Price AE, Fajardo M, Grossman JAI. Reoperation for
failed shoulder reconstruction following brachial
plexus birth injury. J Brachial Plex Peripher Nerve Inj
2013;8(1):7
8. Ruchelsman DE, Ramos LE, Price AE, Grossman
LA, Valencia H, Grossman JA. Outcome after ten­
don transfers to restore wrist extension in children
with brachial plexus birth injuries. J Pediatr Orthop
2011;31(4):455–457
9. Liggio FJ, Tham S, Price A, Ramos LE, Mulloy E, Gross­
man JAI. Outcome of surgical treatment for forearm
pronation deformities in children with obstetric brachi­
al plexus injuries. J Hand Surg [Br] 1999;24(1):43–45

1300
CHAPTER
67
Many complications of upper extremity nerve decompres­
sions initially present to the office as a patient inquiry
about persistent or worsening paresthesias despite surgi­
cal decompression. In the early postoperative period, and
with the absence of obvious infection, the most common
provider response is undoubtedly that it should continue to
improve with time. Unfortunately, there are complications
that must be recognized for which interventions other than
tincture of time are indicated to achieve the most optimal,
long-term patient outcomes.
There are many journal reviews related to the incidence,
complications, and subsequent management of nerve com­
pression syndromes; however, the actual incidence of com­
plications is not as clear.1–5 Overall, reported incidence of
nerve compression syndromes can be quite high. Carpal tun­
nel, for example, is reported to have a lifetime prevalence of
3 to 6%, making it the most common upper limb neuropathy
and accounting for more than $500 million dollars of health
care–related costs in the United States.1,6,7 Complications
after carpal tunnel release are reported as 1 to 25%, with
reoperation rates as high as 12%.8 Reported complications
with cubital tunnel are similar, with reported complication
rates of 3 to 20%.2,9 Additional nerve compression syndromes
such as pronator syndrome, anterior interosseous nerve syn­
drome, posterior interosseous nerve syndrome, and Wart­
enburg’s syndrome (superficial radial neuritis) have much
less published data for analysis of complication rates and
subsequent reoperation rates. Overall the incidence of both
nerve decompressions and complications is difficult to de­
fine, with wide reported ranges. This results in a potentially
large number of compilations that must be accurately diag­
nosed and treated accordingly.
Carpal tunnel release is worth noting specifically given
its high reported incidence. With such a common presen­
tation, it is no surprise that it is one of the most common
outpatient, elective surgical procedures, with more than
500,000 surgeries performed in the United States each
year.10 The procedure is often considered easy to perform;
therefore many different surgical specialties perform it. The
various methods for carpal tunnel release have been well de­
scribed in the published literature, and complications associ­
ated specifically with median nerve decompression do not
seem to be related to specific surgical approaches in most
cases.11 However, complications of carpal tunnel release are
reported to be as high as 25%.8 It is these complications that
leave both the patient and surgeon with significant frustra­
tion.
When things don’t go well after nerve decompression, a
wrong diagnosis, an inappropriate operation, patient com­
pliance, and unexpected events all become part of one’s
thought process. This chapter focuses specifically on com­
plications and deviations from the expected recovery course
after upper extremity nerve decompression.
Avoiding Unfavorable Results
and Complications in Nerve
Decompression Surgery
Preoperative Planning and Assessment
Thorough and accurate preoperative assessment of any
neuropathy is essential in determining the presence of
nerve compression, the potential surgical indication, and
the appropriate procedure. It is important not only to ex­
amine the entire length of nerves on patients with neu­
ropathy but also to document clinical examination findings
at the time of evaluation (Fig. 67.1). Later comparison and
evaluation may be required in the event of either a com­
plication or a slower than expected recovery. The most
common compression neuropathy symptoms are numb­
ness, tingling, dropping objects, positional triggering of
symptoms, and waking at night with numbness. Find­
ings on examination are Tinel’s sign, neuropathic pain,

Nerve Decompression Surgery
Allen L. Van Beek, Jason D. Fowler, and Holly S. Ryan

1301
Chapter 67 Nerve Decompression Surgery
ever, electrophysiology should also be considered when
evaluating atypical presentations, “difficult patients,” and
circumstances in which workers compensation or litigation
are factors. Ultimately, when the patient is not progressing,
the surgeon needs to delineate whether persistent or recur­
rent compression or other possible surgical complications,
such as nerve laceration, injury to surrounding structures,
or inaccurate original diagnosis, may have occurred. When
the patient is unhappy and the outcome not as expected,
the surgeon will be pleased to have accurately documented
findings before surgery and had patient discussion regard­
ing surgery and its potential complications.
When physical examination and electrophysiological
studies remain unclear regarding the site of compression or
specific diagnosis, imaging should be considered. Narrow­
ing, swelling, radiological signs of inflammation, and even
nerve transection documented by imaging provide valu­
able information to the surgeon concerning preoperative
diagnosis and postoperative complications. The advent of
high-resolution ultrasound and magnetic resonance imag­
ing (MRI) allow for more specific and reliable anatomical
evaluation of nerves. Recent advances in ultrasound have
added another evaluation tool for carpal tunnel syndrome
(CTS) by evaluating the cross-sectional area of the median
nerve through the carpal tunnel. Ultrasound imaging may
provide additional benefit by identifying structural anoma­
lies within the tunnel.14 Also described are using ultrasound-
guided carpal tunnel releases and ulnar nerve releases as
a potential method to reduce intraoperative nerve injury
when using short-scar techniques.15–17 Additionally, some
authors report that cubital tunnel syndrome can present
with normal electromyography (EMG) and that ultrasound
or MRI can aid in diagnosis if the clinical examination is
not convincing.18 Overall, imaging is not necessary or the
standard of care in the treatment of upper extremity nerve
decreased sensibility, muscle wasting, positive provocative
tests with pressure, or fulcrum stress.3,12 Ancillary testing
such as nerve conduction, neurophysiological, and imaging
studies and ultrasound can be useful when the diagnosis
is complex or indeterminant. There is little consensus on
the “gold standard” for upper extremity compression neu­
ropathy, and many patients receive operations based on
their history and clinical assessment. It is accepted that
electrophysiology can provide additional support for a di­
agnosis, and in some insurance plans it is required before
surgery is approved. Electrophysiological studies are espe­
cially helpful if complications arise after surgery.13 How­
Summary Box
Complications of Nerve Decompression
Surgery
•• Injury to the palmar cutaneous branch of the
median nerve
•• Injury to the recurrent motor branch of the
median nerve
•• Injury to the medial antebrachial cutaneous nerve
•• Median nerve laceration
•• Ulnar nerve kinking
•• Ulnar motor branch injury during median nerve
decompression
•• Incomplete median nerve release
•• Synchronous pronator or anterior interosseous
nerve syndrome (AINS)
•• Posterior interosseous nerve compression
•• Unexpected and unsuspected diagnoses
Motor
Brain
Central nervous system
Examine the entire nerve length
Sensory
Fig. 67.1 It is essential the entire peripheral nerve be examined, starting at the spinal cord and continuing the examination distally for both
motor and sensibility functions.

SECTION VIII THE HAND AND UPPER EXTREMITY
1302
If recurrence is documented and the symptom-free in­
terval is over a period of years, repeat nerve decompres­
sion is recommended. As with persistent compression,
care should be taken to avoid injuring the nerve by care­
ful proximal and distal exposure before exploring the area
of ­concern. Usually only a decompression would be neces­
sary; however, adjuvant procedures can be used depending
on the specific findings and surgeon judgment at the time
of ­exploration and release (such as a vascularized pedicle
fat flap).
Synchronous Pathology
The potential of antecedent synchronous pathology must
be considered when evaluating a patient who is not im­
proving. Although not a direct complication of surgical
release, ideally the original evaluation would have discov­
ered the synchronous pathology and considered additional
treatment in conjunction with the original decompres­
sion surgery. When this is not the case, both the patient
and physician can become frustrated with less-than-ideal
outcomes after nerve decompression. Significant synchro­
nous pathology that was undetected during preopera­
tive assessment often leads to persistent symptoms after
­decompression.
Pathology more proximal in the nerve distribution
caused by compression, spinal foramen narrowing, thoracic
outlet syndrome, demyelinating diseases, and syringomyelia
are all reported as sites of synchronous nerve compression
or pathology.23,24 As with other persistent nerve compres­
sion symptoms, imaging, nerve conduction velocity, EMG,
and careful clinical examination can accurately determine
nerve status. When evaluating a patient for perceived syn­
chronous pathology as the cause for failure to improve, the
surgeon should compare the new postoperative findings to
those noted preoperatively. If synchronous pathology is a
proximal or distal peripheral nerve compression, release at
that compression site may improve symptoms if the nerve
has not become irreversibly damaged.
Preoperative undetected neuropathic disease like dia­
betes, demyelinating disease, and infectious disease are po­
tential synchronous pathologies that may complicate or limit
recovery. As with additional sites of compression, detection
of neuropathy before operative release is ideal, because this
can direct patient expectations after nerve release. If preop­
erative nerve conduction studies are available, the surgeon
will be able to assess more accurately the severity, site, and
management of the neuropathy. Fibrillation potentials, posi­
tive sharp waves, and conduction times that are very slow
all point to pathology that may not completely recover after
nerve decompression.
Direct Nerve Injury
When not recognized or not reported during an operation,
occult direct nerve injury can be an initially frustrating and
later a feared complication in follow-up visits. Direct nerve
injury can be a result of patient positioning, thermal injury,
compression syndromes, but it can be a valuable tool in the
presence of a broad differential diagnosis.
Persistent Nerve Compression
The rate of incomplete release is approximated at 9 to 23%
for carpal tunnel,19–21 namely related to incomplete release
of the distal flexor retinaculum. Incomplete cubital tunnel
release resulting in revision has been reported, but there is
limited data describing the incidence.22 Incomplete release
for other upper extremity compression neuropathies is not
well described. In our experience, accurate diagnosis and
careful thorough decompression has not resulted in persis­
tence or early recurrence.
After release of a compressed nerve, if symptoms recur
in the early postoperative period, persist, or become worse,
incomplete nerve release and persistent compression should
be strongly considered. Care should be taken to fully evalu­
ate the patient for other causes of continued nerve symp­
toms despite release. If the likely cause of symptoms remains
persistent compression rather than other sources, open de­
compression should be performed, and adjunctive proce­
dures will probably be necessary. When reexploring a nerve
that has had an injury, previous surgery adjacent to the
nerve, or previous decompression, the surgeon must iden­
tify the nerve distal and proximal to the zone of previous
surgery before exploring the area of concern. The surgeon
should follow the nerve into the zone of injury from proxi­
mal and distal healthy nerve to assess, release, and resolve
the nerve problem as appropriate. Directly approaching the
nerve in the zone of previous surgery is likely to produce an
injury to the nerve because of adjacent and adherent scar
formation further complicating patient outcome and treat­
ment. Once completely released, adjuvant procedures such
as local vascularized pedicle fat flaps, venous tube wraps,
collagen, or acellular dermal matrix wraps or transposition
to a new position would be recommended.
Recurrent Nerve Compression
The term recurrent compression syndrome is usually re­
served for individuals who have had nerve decompression
surgery with symptomatic relief or significant improve­
ment lasting for a period of months or years. In our expe­
rience, late recurrence is very rare and is most commonly
observed in males with heavy repetitive work activities. Af­
ter the symptom-free interval, progressive nerve compres­
sion clinical symptoms and worsening electrophysiological
tests begin to occur. Patients presenting with these symp­
toms should have a thorough repeat evaluation from nerve
root to end organs. The question then becomes whether
this is a recurrence or an entirely new site of pathology.
Clinical examination coupled with electrophysiology stud­
ies will help to further elucidate recurrent compression.
Generally, when an entirely symptom-free period or dra­
matic improvement has occurred and the patient develops
recurrent symptoms, it is appropriate to consider this as a
recurrent compression.

1303
Chapter 67 Nerve Decompression Surgery
electrophysiogical capability, and microsurgical skills. The
intervention choice should be performed according to the
surgeon’s discretion based on preoperative assessment re­
inforced with intraoperative findings.
Managing Unfavorable Results
and Complications in Nerve
Decompression Surgery
Complications Associated with Nerve
Decompression
Injury to the Palmar Cutaneous Branch
of the Median Nerve
The palmar cutaneous branch of the median nerve (PCBMN)
originates from the median nerve 5 to 10 cm above the
wrist crease and courses on the radial side of the palmaris
longus tendon and third metacarpal shaft. An incision that
is too radial to those landmarks risks injury to the PCBMN.
The resulting hypothenar dysesthesia, combined with a
hypersensitive neuroma, lead to a less-than-ideal outcome
(Fig. 67.3).
Injury to the Recurrent Motor Branch
of the Median Nerve
The recurrent motor branch of the median nerve (RBMN)
is usually located distal to the transverse carpal ligament
but may also be through the ligament. Always transecting
the ligament adjacent to the hook of the hamate will pre­
vent injury to the RBMN when it is anomalous in location
(Fig. 67.4). Injury to the RBMN will lead to thenar muscle
atrophy, loss of opposition, and weakness during key pinch
functional activities.
crush injury, traction injury, injecting with large-caliber
needles, direct suture of nerve, or cutting the nerve. Careful
and attentive positioning will help to prevent temporary
compression-related neuropathies secondary to prolonged,
focal pressure or nerve stretch. Thermal injury can be
minimized with the use of bipolar cautery. Care should
be taken to retract and handle nerves with care to avoid
traction or crush injury, and “Rope” retractors should not
be used around the nerve. Adequate exposure and the use
of operative loupes are indicated to ensure adequate identi­
fication and visualization of the nerve being decompressed,
especially when the surgical site is fibrotic. When closing
incisions, the surgeon must be careful to prevent injury to
the nerve with a suture needle (Fig. 67.2) or strangulation
of the nerve by including all or a portion of the nerve in the
wound closure.
The incidence of direct nerve injury is low for carpal
tunnel release and is usually attributed to anatomical varia­
tions of the thenar motor branch of the median nerve.4,25
Similarly, iatrogenic injury to the ulnar nerve during cubital
tunnel release has a low incidence, probably because fewer
classes of surgeons release this nerve. In my experience, ex­
cessively short scars provide poor visualization unless an en­
doscope is used. In addition, the scissor “sliding” technique
required with very short scar approaches puts the nerve
being decompressed, as well as proximal nerve branches,
at risk for laceration. Use of ultrasound guidance may im­
prove safety. Many types of injury that do not involve direct
nerve injury will improve with time. If the nerve does not
improve and the Tinel’s sign does not progress distally, elec­
trophysiology and careful clinical assessment should be able
to isolate the site of nerve injury. When irreversible nerve
injury is suspected, such as severe thermal injuries, crush
injuries, or partial or complete nerve laceration, explora­
tion and repair is indicated. If nerve transection or neuroma
is discovered, the decision for neurolysis, resection of neu­
roma with direct repair, or resection of neuroma with nerve
graft all require significant surgical judgment, intraoperative
27-gauge needle
nominal outer
diameter ≈0.4 mm
27-gauge needle size
compared with a single
digital nerve fascicle
Fig. 67.2 It is essential to use small-caliber needles when injecting medications around peripheral nerves. The yellow triangle accurately
represents the size of a 27-gauge needle. It is superimposed over a digital nerve fascicle. The 27-gauge sharp needle could easily transect
an entire fascicle. An even larger needle could transect a small branch nerve or digital nerve. When injecting around nerves, small-caliber
and tapered needles are ideal. Ultrasound-guided injections are also important for avoiding nerve injury during medication injection and
when performing axillary nerve blocks for surgical anesthesia.

SECTION VIII THE HAND AND UPPER EXTREMITY
1304
surrounding the nerve. Injury to the MABC might also be
associated with ulnar kinking because of inadequate re­
lease of the aponeurosis of the flexor carpi ulnaris or fail­
ure to remove the medial intermuscular septum (Fig. 67.5).
MABC and kinking seem to be closely associated when sec­
ondary surgery is necessary. In these cases, surgical explo­
ration should proceed with careful exposure of the nerve
proximal and distal to the injury site to prevent inadvertent
injury to the nerve.
Injury to the Medial Antebrachial
Cutaneous Nerve
The most commonly reported complication of cubital tun­
nel release is medial antebrachial cutaneous nerve (MABC)
injury, kinking, and fibrosis. The incidence is reported to be
between 5 and 15%.26 Should a patient present with injury
to the MABC after cubital tunnel release, secondary explo­
ration can be difficult because of dense perineural fibrosis
Palmaris longus
Neuroma
Fig. 67.3 A palmar cutaneous branch of the median nerve
injury from open carpal tunnel release in which the primary
surgeon’s incision followed the thenar crease.
Fig. 67.4 The recurrent motor branch of the median nerve leaves
the median nerve where the third metacarpal crosses the thenar
crease, and it penetrates into the thenar muscle fascia for muscle
innervation.
Sterile tourniquet
Ulnar nerve
Medial antebrachial
cutaneous nerve
neuroma
Fig. 67.5 Medial antebrachial cutaneous nerve neuroma after open cubital tunnel release with subcutaneous transposition. The nerve was
kinked (dotted line).

1305
Chapter 67 Nerve Decompression Surgery
to ensure that the aponeurosis of the flexor carpi ulnaris is
not compressing it and that proximal anomalous ligaments
are released (Fig. 67.7). After transposition of the nerve, the
ulnar nerve should follow a gentle course along the route
of transposition without any new compression or acute
angles during elbow flexion and extension.
Ulnar Motor Branch Injury After Median
Nerve Decompression
Very rarely, the ulnar motor branch can be injured during
carpal tunnel release. The patient in Fig. 67.8 presented
with intrinsic muscle atrophy after an open carpal tunnel
release without additional associated compression symp­
toms to indicate a Guyon’s canal or cubital tunnel compres­
sion. On reexploration, an injury to the ulnar motor branch
as it courses around the hook of the hamate, dorsal to the
flexor tendons, was discovered. It is likely that the nerve was
Median Nerve Laceration
Nerve injury associated with previous carpal tunnel release
is rare and is cited as occurring in less than 1% of cases.5 The
laceration can involve part of the nerve or the entire nerve.
When the nerve has a partial injury, use of the microscope
for careful preservation of intact fascicles is necessary.
Injured fascicles should be resected to healthy nerve and
repaired primarily if possible. Nerve grafting is required if
direct repair creates tension or nerve kinking. The ultimate
method of repair is determined by the findings and judg­
ment of the surgeon at the time of exploration (Fig. 67.6).
Ulnar Nerve Kinking
If the ulnar nerve is transposed, it is essential to have ad­
equate releases proximal and distal to prevent kinking of
the nerve that produces nerve irritation and pain when the
elbow is used. If the nerve is not transposed it is necessary
Fig. 67.6 Median nerve laceration. (a) A painful Tinel’s sign in combination with a short scar used by the referring surgeon. (b,c) The lac­
eration occurred when the referring surgeon used a short-scar incision with a scissor slitting technique. There is a proximal neuroma on the
left and a partially intact nerve on the right.
Short scar
Painful
Tinel’s sign
a
b
Distal nerve
Intact nerve
Proximal
neuroma
c
Fig. 67.7 Kinking of ulnar nerve at the flexor retinacu­
lum after ulnar nerve subcutaneous transposition.
Course of ulnar nerve
Medial antebrachial
cutaneous nerve

SECTION VIII THE HAND AND UPPER EXTREMITY
1306
will be weakness of the flexor pollicis longus and flexor
digitorum profundus muscles to the index and long fingers.
Tinel’s sign and pressure-provocative testing may be pres­
ent at the elbow along the course of the median nerve. In
Fig. 67.10, an anomalous tendinous band was creating an
area of narrow compression on the median nerve at the
level of the elbow. The patient had persistent median nerve
symptoms after carpal tunnel release.
Posterior Interosseous Nerve Compression
Posterior interosseous nerve (PIN) compression can be con­
fused with lateral epicondylitis and may not be detected
until after management of epicondylitis has failed. The illus­
tration shows the differing location of lateral elbow pain for
PIN syndrome and lateral epicondylitis. Lateral epicondylitis
diagnosis can sometimes be confirmed by using MRI and de­
tecting tears in the common extensor aponeurosis. Of note,
PIN syndrome may be a sequelae of radial head fractures or
dislocations. Clinically distinguishing PIN syndrome and lat­
eral epicondylitis may be difficult when both are present in
the same patient. If both are clinically present and surgery
is needed, it is recommended that the PIN be decompressed
concomitant with lateral epicondylectomy and extensor
slide. Approach to this nerve is usually between the muscle
bellies of the mobile extensors and the immobile extensor of
the dorsal radial aspect of the elbow (Fig. 67.11).
transected as the blade used to release the transverse carpal
ligament slipped dorsally when it completed the release.
Incomplete Median Release
Incomplete release of the transverse carpal ligament and
distal aspect of the deep forearm fascia are difficult to de­
termine clinically at secondary exploration, because fibro­
sis alters the appearance of the anatomical fascia. A short
scar and narrow segment compression with what appears
to be a nonfibrotic transverse ligament are clues as to pos­
sible incomplete release. Fig. 67.9 is an example of nerve
appearance after a previous carpal tunnel release, which
was explored secondarily to reveal that the proximal por­
tion of the ligament had not been released because of the
proximal pseudoneuroma formation.
Synchronous Pronator or Anterior
Interosseous Nerve Compression
Median nerve compression and pathology can be located
across any of the upper extremity joint fulcrums. The most
common is the carpal tunnel. However, the nerve can be
compressed at the elbow and mimic many of the symptoms
associated with CTS. Clinical examination of more proximal
compression will yield other findings in addition to isolated
compression at the carpal tunnel. In advanced cases there
Fig. 67.8 (a) Intrinsic atrophy from an ulnar motor branch transection during carpal tunnel release. (b) The dotted line represents the ap­
proximate course of the motor branch as it courses around the hamate hook and supplies branches to the intrinsic muscles.
a
Ulnar motor
branch foramen
b
Wrist
crease
ê
Fig. 67.9 The star identifies a median nerve pseudoneuroma after an incomplete carpal tunnel release.

1307
Chapter 67 Nerve Decompression Surgery
Fig. 67.11 (a) A sterile tourniquet is necessary for safe and accurate anatomical dissection and release. (b) Exposure of the posterior in­
terosseous nerve as it courses under the proximal edge of the supinator muscle. (c) Appearance of the nerve constriction after removal of
the tendinous edge of the supinator.
Sterile
tourniquet
5 cm
Incision
Lateral
epicondyle
Posterior
interosseus
nerve
a
Supinator
Posterior
interosseus
nerve
Pseudoneuroma
b
Compression
c
Fig. 67.10 (a) The deep head of the pronator tendon origin can compress both the anterior interosseus nerve and the median nerve.
(b) Proximal median nerve compression.
Released band
compressing
median nerve
Median nerve
b
Median nerve
Released deep (ulnar)
head of pronator
Stump of the ulnar head
of the pronator teres muscle
Posterior interosseus nerve
a
Continued

SECTION VIII THE HAND AND UPPER EXTREMITY
1308
the patient’s symptoms continued and limited work ac­
tivities because of pain when using a screwdriver. Clini­
cal symptoms of numbness and nerve conduction studies
improved postoperatively, but pain persisted. MRI revealed
what was determined to be a large neural tumor. Removal
alleviated the residual symptoms.
Unexpected and Unsuspected
Diagnoses
The patient in Fig. 67.12 presented with clinical and elec­
trodiagnostic findings of CTS and underwent open carpal
tunnel release. During the postoperative recovery period
Fig. 67.11, cont’d (d) The approach to the nerve between the mobile and immobile portions of the extensor muscles distal to the lateral
epicondyle. The division of the radial nerve into its superficial sensory component and its motor posterior interosseous component will be
visualized.
Posterior
interosseus nerve
Lateral epicondyle
Arcade of Froshe
Mobile extensors
Immobile extensors
Remnant of
arcade of Froshe
Superior aponeurosis
Compression
Proximal edge
of supinator
d
Fig. 67.12 (a) This patient presented with sensitive nodules and was noted to have multiple nerve sheath tumors. Contrast magnetic reso­
nance imaging revealed a neural tumor presenting as a median nerve compression after a failed carpal tunnel release. (b) The tumor that
was removed, which alleviated the symptoms of carpal tunnel syndrome.
b
a

1309
Chapter 67 Nerve Decompression Surgery
compensation-related injury.30–32 The incidence of compres­
sion syndromes seems to be increasing, often believed to be
work related or simply due to earlier detection. However,
the literature is controversial when it comes to support for
nerve compression syndromes as being related to repeti­
tive motions associated with the workplace. Thoroughness
of evaluation and explanations help assure the patient of
empathetic care and concern.
Persistent neuropathy or symptoms 6 months after
nerve release for nerve compression is usually secondary to
irreversible pathology, wrong diagnosis, wrong operation,
or something unknown or unrecognized happening during
surgery. Thorough clinical examination and judicious use
of ancillary studies such as electrophysiology, ultrasound,
and MRI will help to resolve which explanation seems most
probable.
Conclusion
Nerve compression syndromes are common, resulting in
large numbers of decompression nerve surgeries annu­
ally. Appropriate, thorough, and thoughtful preoperative
evaluation and documentation will reduce negative out­
comes and be a valued asset if incomplete recovery occurs.
Adjunctive testing and imaging studies should be used for
clarification of a poorly defined diagnosis preoperatively
and uniformly for evaluation of complications or unex­
pected outcomes after surgical decompressions.
Although rare, the complications of nerve decompres­
sion can be avoided by understanding the anatomy, ade­
quate exposure, careful technique, optical magnification,
and enhancement with surgical loupes, endoscopes, and
ultrasound. When a direct injury is likely to have occurred,
timely treatment is indicated to ensure optimal patient
outcomes.
Postoperative Considerations and
Complications
Generally, the use of narcotics to control postoperative pain
is minimal and can often be avoided entirely. Severe and
persistent pain after nerve decompression is unusual and
should alert the surgeon to the potential of nerve injury.
Chronic pain associated with neuropathy responds well to
nonnarcotic pain medication such as gabapentin, amitrip­
tyline, and nonsteroidal anti-inflammatory medications. In
our experience, patients requiring significant amounts of
narcotic pain medication postoperatively are unusual and
should alert caregivers to reexamine and document what
is occurring.
Patients may confuse pain and nerve irritation in the vi­
cinity of previous symptoms with failed release even when
their primary symptoms have improved. This highlights the
importance of preoperative documentation to allow the sur­
geon to distinguish between persistent symptoms and new
onset of new symptoms. For example, injury to the PCBMN
during carpal tunnel release can result in burning dysesthe­
sias over the thenar eminence that may be confused with
persistent CTS.27 Also, an injured medial antebrachial cu­
taneous nerve during cubital tunnel release will produce
hypersensitivity over the cubital tunnel combined with
numbness down the forearm.28,29 These two circumstances
are not persistent compression but complications and may
be perceived by the patient as failed nerve decompression.
Patient compliance regarding therapy, mobilization, and
utilization become important factors to consider when pa­
tients are not doing well after surgery. Pain is often a hall­
mark for those patients and an ongoing frustration that can
limit work, social, and financial status. Recent literature
demonstrates a delayed return to work in the nerve com­
pression syndromes that are treated as part of a workman
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Anatomical Variations of the Median Nerve in the Carpal
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open carpal tunnel release. J Hand Surg Am 1999;24(3):
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mating the prevalence of delayed median nerve con­
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7. Palmer DH, Hanrahan LP. Social and economic costs of
carpal tunnel surgery. Instr Course Lect 1995;44:167–172
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9. Shi Q, MacDermid JC, Santaguida PL, Kyu HH. Predictors
of surgical outcomes following anterior transposition of
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view. J Hand Surg Am 2011;36(12):1996–2001.e1, 6
10. Gelfman R, Melton LJ III, Yawn BP, Wollan PC, Amadio PC,
Stevens JC. Long-term trends in carpal tunnel syndrome.
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ferent type of myelopathy hand in patients with cervical
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current cubital tunnel syndrome. Etiology and treatment.
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Discussion by Ivica Ducic
Unfortunate scenarios after upper extremity nerve de­
compressions rarely occur. They are probably under­
reported. However, it is important to define the most
likely causes of undesired presentation after nerve de­
compressions, such as underlying mechanism of nerve
injury and its location, and then determine potential
corrective repair options. In reconstructive microsur­
gery, microvascular anastomosis itself is only a part of
the entire reconstructive process, because the choice
of the flap and its orientation, insetting, and functional
durability play important roles in final overall recon­
structive success. Similarly, in nerve surgery, extensive
research over the past few decades contributed to the
development of new reconstructive technologies and
thereby improved the surgeon’s technical abilities
to treat nerve injuries. Despite these advancements,
fundamental principles of nerve surgery cannot be
overlooked, such as understanding the cause of the
original presenting nerve problem or timing of nerve
repair, which becomes equally important when aim­
ing at optimal outcome. Although scientific discussion
continues on preferred technical details, the science is
still unclear and not fully validated, because various
technical approaches may provide similar outcomes,
diminishing the existence of outdated “gold standards”
or “best technique” in nerve surgery.
Before considering the various treatment options, it
is important to first define the most likely reason why
nerve surgery failed to help or why perioperative com­
plications followed. Although each factor has its specific
value and importance, the several need to be considered.
Reasons for Failed Nerve Surgery
or Complications
Initial Severity of the Problem
A patient with such severe median nerve compression
at the carpal tunnel as to cause thenar atrophy and
anesthesia at the fingertips may not improve despite
adequate decompressive surgery (Fig. 67D.1). Miss­
ing the opportunity to point this out to the patient

1311
Chapter 67 Nerve Decompression Surgery
preoperatively may lead to the patient feeling that sur­
gery was a failure. In fact, recovering dysesthesias may
be interpreted as worsening symptoms after surgery. In
a patient with muscle atrophy and impaired function,
the surgeon may perform tendon transfers preemp­
tively in anticipation that there will be minimal motor
recovery.
Initial Indications for Surgery
Despite the many diagnostic tools available to diag­
nose nerve problems, often results can come back as
indeterminate or falsely negative, even though the pa­
tient objectively presents with nervelike problems. In
such scenarios, and always when evaluating patients
with functional deficits, chronic pain, or nerve-related
symptoms, especially after previous nerve surgery, it is
important to retake a detailed history relevant to the
current presentation, observe the patient’s responses
during the examination, and perform the relevant
physical examination. These important steps might
contribute much more to establishing the diagnosis
and understanding the cause of the patient’s existing
problem than any radiological or electrophysiological
testing tool. In other words, the surgeon should make a
fresh start with the history and thorough physical ex­
amination and try to avoid preconceived biases.
Timing of Surgical Intervention
Once a patient has previously undergone nerve surgery
followed by failure to resolve preoperative symptoms,
the surgeon needs to determine the most likely reason
for failure. The patient’s symptoms, the diagnostic eval­
uation, and the type of surgery performed determines
whether, what, and when additional surgical interven­
tions should take place. The surgeon needs to be certain
that sufficient time has elapsed for full potential nerve
recovery to have occurred. In contrast, needless delays
in intervention may lead to further harm with pro­
gressive muscle atrophy and onset of a pain syndrome
that becomes difficult to treat. This requires a team ap­
proach among the surgeon, the patient, and sometimes
other specialists, especially if comorbidities are pres­
ent. Although there is a common misconception that it
takes time for nerves to regenerate and to note an im­
provement, evidence-based data strongly support early
surgical intervention if nerve ­compromise is suspected.
Fig. 67D.1 (a) This patient with severe thenar muscle atrophy related to carpal tunnel syndrome has a total inability to abduct
the thumb. (b) Pronounced constriction of the median nerve was seen at the time of carpal tunnel release. (c) In anticipation of
the fact that the muscle will not recover, the surgeon can perform a simultaneous Camitz (palmaris longus) tendon transfer to
accomplish thumb abduction and opposition. (d) Postoperative thumb function is excellent because of the preemptive tendon
transfer that was performed. Courtesy of David T. Netscher.
a
b
c
d

SECTION VIII THE HAND AND UPPER EXTREMITY
1312
By ignoring this principle, extremely valuable inter­
vention time can be lost, with potentially irreversible
nerve damage and less likelihood of recovery, because
it takes time for nerves to regenerate, and during this
time sensorimotor recovery may no longer be possible.
Comorbidities and Double Crush
Syndrome
Poorly controlled diabetes, which is among the most
prevalent comorbidities, has direct negative conse­
quences on the outcome of nerve decompression sur­
gery. Similarly, any underlying comorbidity, either
metabolic or anatomical, along the path of the nerve
and potentially affecting nerve function or regenera­
tion needs to be addressed, because it might contribute
to nerve surgery failures.
Double crush syndrome was originally described for
patients who have both a more distal nerve compression
and a neck lesion. However, this has been expanded to
include patients with more than one cause of neurop­
athy, either through multiple-level compression areas
or associated metabolic causes. The patient may have
persistent symptoms if these other causes were unrec­
ognized.
Postoperative Complications
Surgeons’ acknowledgment of postoperative compli­
cations and timely intervention play an important
role when aiming to help a patient whose postop­
erative course deviates from expectations. Thus ex­
cessive edema, hematoma, seroma, or infections can
contribute to prolonged and increased pain, pares­
thesia, and/or functional deficits (clinical judgment
is required to define what intervention is required
and how soon). With patients who clinically pres­
ent with these conditions, earlier intervention or
exploration is a safer option than denial, because
delay results in protracted recovery and suboptimal
outcome (Fig. 67D.2).
Surgeon Experience and Properly
Executed Surgery
Although not as openly discussed, primarily because
of the entitlement of some and/or respect to others,
surgeon expertise for a given surgical procedure
plays an important role in minimizing complications.
Although many different specialists were exposed to
nerve surgery during their training and are capable of
providing treatment for nerve-related problems, it is
the surgeon’s judgment call when a presenting nerve
problem falls outside of usual practice, requiring a
more specialized approach and expertise. The decision
to refer at that point or to carry on treatment might re­
sult in a wide range of potential outcomes from success
to failure of attempted surgery. An in-depth under­
standing of anatomical variations, different technical
approaches for the same problem, and surgeon exper­
tise in nerve surgery are among several important vari­
ables that optimize patient outcome.
Fig. 67D.2 (a) This patient had persistent pain and dysesthesias after open carpal tunnel release with a pronounced Tinel’s sign
at the site of the dot. Careful history taking revealed that this was a new symptom after surgery, and clinical examination showed
improved fingertip sensation but dysesthesias in the palm. (b) Surgical exploration revealed a traumatic neuroma of the palmar
cutaneous nerve branch of the median nerve. A preoperative selective nerve lock may also have been helpful in the preoperative
diagnosis. *, palmaris longus; x and arrow, palmar cutaneous branch of median nerve neuroma. Courtesy of David T. Netscher.
a
b

1313
Chapter 67 Nerve Decompression Surgery
Expecting the Unexpected
When performing nerve surgery, the surgeon needs to
have a thorough knowledge of normal anatomy to be
able to recognize abnormal nerve anatomy and abnor­
malities of the surrounding soft tissues, especially those
that may cause compressive neuropathy (Fig. 67D.3).
In terms of nerve reconstruction, with the evolu­
tion of evidence-based medicine, we learned that sev­
eral variables can equally and cumulatively contribute
to the failure of nerves to regenerate. The first, already
mentioned, is the timing of nerve surgery and the de­
lay in executing nerve decompression or reconstruction,
thereby allowing the progression of Wallerian degen­
eration and minimizing the chance for nerve recovery.
Often overlooked, the tension at the repair site will ad­
versely affect vascular perfusion of the reconstructed
nerve ends, and thus ultimately the outcome, because of
the decrease in the number of regenerating axons across
the gap. Equally important is underresection of oppos­
ing traumatized nerve ends, with higher-than-optimal
fibrous scar versus the neuronal tissue ratio. Finally,
fascicular misalignment of opposing nerve ends may
undermine any nerve recovery and may even require
additional nerve surgery procedures to address reoc­
currence of pain related to neuroma in continuity. To
overcome these potential obstacles, the nerve surgeon
needs to pay close attention to each mentioned variable
and address it appropriately.
Advancements in science and technology have pro­
vided further refinements in nerve surgery through de­
velopment of nerve connectors, conduits, protectors,
and human allograft, enabling reconstruction of nerve
defects up to several centimeters when appropriately
applied for a suitable defect size. Although it may still
be indeterminate which is the most appropriate recon­
structive device, the development of new technologies
raises awareness of their limitations, thereby helping us
identify the most appropriate clinical scenario in which
each technology would be applicable and to minimize
failure complications of misuse.
Even with the best intentions to help the patient,
applying all of the aforementioned variables and tech­
nologies while obeying the principles of nerve surgery,
failure of nerve decompression or reconstruction can
follow with persistence or even worsening of patient
functional status. There is no better example than the
care of a patient with chronic pain. These patients are
often managed by lengthy and ineffective conservative
treatments, in which previous providers focused on pa­
tient symptoms rather than the anatomical cause of the
problem. This may contribute to escalating peripheral
sensitization and to central sensitization, making pa­
tient treatment more challenging.
The development of chronic pain syndrome is prob­
ably the most devastating outcome of any nerve surgery
and can follow any nerve surgery, regardless of how mi­
nor or extensive it is. Poor and often overlapping bound­
aries of each specialist’s expertise is for the most part to
blame for why there is no better structured way to treat
patients continuing to have or developing new chronic
pain after nerve surgery. At the same time, despite prop­
erly executed nerve surgery, some patients can experi­
ence completely unexpected worsening of symptoms,
without apparent anatomical explanation. In these situ­
ations, involvement of a pain specialist, physical thera­
pist, and/or clinical psychologist may address patient
Fig. 67D.3 (a) A clue to the reason for failure of relief of numbness in the fingertips after prior open carpal tunnel release is iden­
tified in this patient unable to flex and oppose the little finger. (b) With a more extensile exposure, extending proximally across
the wrist crease into the distal forearm at the time of revision surgery reveals the problem. An abnormal flexor/opponens of the
little finger is found arising in the distal forearm and passing through Guyon’s canal on the way to the little finger. This abnormal
muscle belly was causing compression on both median and ulnar nerves. Courtesy of David T. Netscher.
a
b

SECTION VIII THE HAND AND UPPER EXTREMITY
1314
needs in dealing with chronic pain. Certainly if an an­
atomical reason is suspected, efforts should be made
to address those surgically, provided the patient agrees
with reoperation. If no anatomical explanation is obvi­
ous, interventional pain management specialists and/or
a clinical psychologist might better serve those patients
than reoperation. Although nerve regenerative science
continues to evolve, consideration of all the aforemen­
tioned variables, individually tailored to the patient-
specific presentation, should enable the best possible
outcome. The plastic surgeon should always be a pa­
tient advocate, trying to make the patient more comfort­
able and functionally improved by alternative methods
while awaiting the long recovery that is inevitable af­
ter nerve surgery. For example, the simple hand-based
orthosis shown in Fig. 67D.4 enables the fingertips to
access a keyboard and function more normally while
awaiting recovery from a posterior interosseous com­
pressive problem.
Conclusion
Although there are many new developments and
technologies in nerve surgery, their optimum role for
complicated nerve surgery has not yet been fully elu­
cidated. When faced with a complication, a thorough
history and clinical examination need to be completed
to avoid missing a previously unrecognized diagnosis.
Timely treatment of any complication must recognize
the importance of nerve regeneration time, but on the
other hand needless delay leads to escalation of muscu­
losensory dysfunction. If necessary, the surgeon should
rely on a physician with special expertise in the latest
developments in peripheral nerve surgery.
Fig. 67D.4 (a) A simple hand-based extension outrigger orthosis provides “lift” to the fingers to access a keyboard and to grasp
around objects (b) during the anticipated recovery of a posterior interosseous palsy after decompression of that nerve by a lipoma
removal in the proximal forearm. Courtesy of David T. Netscher.
a
b
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