Plastic and Reconstructive Surgery Board Review Pearls of Wisdom 3th

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Examination o which upper extremity unctions will test or the condition o the posterior cord?
1. Wrist extension (radial n.)
2. Elbow extension (radial n.)
3. Shoulder abduction (axillary n. via deltoid)

How can the condition o the suprascapular n. be tested?
1. Shoulder elevation (supraspinatus)
2. External rotation (in raspinatus)

What is a strong indicator or a preganglionic lesion at the C8 and 1 nerve roots?
Presence o a Horner syndrome (indicating a lesion o the cervicothoracic sympathetic ganglion [adjacent to C8, 1]).

Dys unction o which nerve will result in scapular winging with orward elevation o the shoulder?
Long thoracic nerve via serratus anterior (SAL —serratus anterior long thoracic).
RADIOLOGY

What is the signi cance o transverse process ractures on the cervical spine x-rays in brachial plexus patients?
May indicate root avulsion.

What ndings on a chest x-ray may point toward a brachial plexus lesion?
Fractures o the rst and second rib.

What is the signi cance o pseudomeningoceles on a cervical C myelogram?
Indicates root-level injury.

What nding would be expected on the chest x-rays o patients with phrenic nerve injury?
Elevation o ipsilateral hemidiaphragm.
ELECTRICAL STUDIES

What do brillation potentials in the EMG indicate?
Denervation o the tested muscles (just like the heart brillates when it is dying).

A ter acute brachial plexus injury, how soon would muscles exhibit brillations in the EMG?
10 to 14 days or proximal muscles and 3 to 4 months or distal muscles.

What evidence can be ound in electrodiagnostic studies o preganglionic lesions?
Preservation o sensory nerve action potentials (SNAPs).

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What is the signi cance o the appearance o nascent potentials in ollow-up EMGs?
Early sign o reinnervation.

What does the presence o intraoperative nerve action potentials (NAPs) across a lesion indicate?
Intact axons.

How many patients with detectable NAPs across a lesion will make a clinically use ul recovery?
90%.

What pattern o NAPs would be expected in a preganglionic plexus lesion?
Accelerated conduction velocity with increased amplitude.

What do motor evoked potentials assess?
Integrity o motor pathway via the ventral root (remember Vroom).

How can the integrity o the sensory pathway via the dorsal roots be tested?
Somatosensory evoked potentials.
TREATMENT PRINCIPLES

When is immediate exploration and primary repair o brachial plexus injuries indicated?
Sharp, open injuries.

What is the pre erred treatment or low-velocity gunshot wounds o the brachial plexus?
Observation, local wound management.

What type o nerve injury is typically associated with low-velocity gunshot wounds?
Neuropraxia.

What is the recommended time rame or brachial plexus exploration in stretch injuries that ail to recover?
3 to 6 months.

What is the order o priority or restoration o unction to the ail extremity?
1. Elbow f exion
2. Shoulder abduction/stability
3. Hand sensibility
4. Wrist extension/ nger f exion
5. Wrist f exion and nger extension

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What type o injury is pre erably addressed with primary nerve repair?
Sharp laceration, not possible in stretch injuries.

What procedure needs to be per ormed to acilitate intraoperative nerve conduction studies?
External neurolysis.

What is the treatment or electrically silent ruptures or neuromas o the brachial plexus that are electrically
silent?
Interpositional nerve gra ting (e.g., sural cable gra t).

What upper extremity unction should be targeted i interpositional nerve gra ting rom a unctioning C5
nerve root is per ormed?
Shoulder abduction (suprascapular, axillary nerves).

What nerve root (when available) should be used to restore elbow exion by interpositional sural nerve
gra ting?
C6 (musculocutaneous n.).

How can triceps unction be restored in a patient with a brachial plexus injury at the trunk level?
By interpositional gra ting rom C7 across the zone o injury.

What is the likely etiology o neuropathic pain a ter brachial plexus reconstruction?
Regenerating axons rom nonavulsed nerve roots.
NERVE TRANSFER

What type o brachial plexus injuries requires the use o nerve trans er (neurotization) to restore unction?
Preganglionic injuries.

How can a nerve trans er accelerate recovery o unction?
By decreasing the distance between the nerve repair site and the end organ (muscle).

What is the Oberlin trans er?
rans er o selected ulnar nerve ascicles in the upper arm to motor branches o the musculocutaneous nerve to the
biceps to restore elbow f exion.

What nerve has been used success ully to neurotize the serratus anterior muscle to address scapular winging?
T oracodorsal nerve.

What unction can be restored by neurotizing the suprascapular nerve with spinal accessory or phrenic nerve?
Shoulder abduction/external rotation.

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What nerve can be targeted in addition to suprascapular nerve to urther improve shoulder abduction?
Axillary nerve.

What nerve trans ers are commonly used or restoration o biceps unction a ter upper trunk disruption?
Medial pectoral nerve to musculocutaneous nerve or the biceps motor branch Oberlin trans er.

What is the advantage o the Oberlin trans er over interpositional nerve gra ts rom C6 to regain biceps
unction?
Faster and more predictable recovery o unction.

In the Oberlin trans er ascicles o the ulnar nerve transmitting which unction should pre erably be used?
Fascicles that stimulate wrist f exion (FCU).

What modi cation o the Oberlin trans er is available to improve recovery o elbow exion strength?
Double ascicular nerve trans er described by MacKinnon, et al.

What additional muscle is targeted in the double ascicular nerve trans er o the Oberlin trans er?
Brachialis muscle.

What donor ascicles are used to neurotize the brachialis muscle in the double ascicular nerve trans er?
FCR or FDS ascicles o the median nerve.

What donor nerves are available or neurotization to restore elbow exion in a “panbrachial” plexopathy
without signs o recovery?
1. Intercostal nerves
2. Spinal accessory via nerve gra ts
3. Phrenic nerve with interpositional gra ts

Comparing intercostal and partial ulnar nerve trans ers to the biceps branch o the musculocutaneous nerve,
which restores elbow exion more success ully?
Partial ulnar nerve (Oberlin).

What is the advantage o a vascularized nerve gra t?
Reinnervation at a aster rate (theoretically).

What contralateral nerve root can be used as a donor o large amounts o motor axons?
C7—usually hal o it.

What unction is addressed by contralateral C7 trans er via vascularized ulnar nerve to the median nerve?
Finger f exion.

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What overall success rate can be expected with nerve trans ers to the musculocutaneous nerve?
71% f exion strength > M3, 37% > M4.

What is the success rate o the Oberlin trans er?
97% or > M3, 94% > M4.

How much shoulder abduction can be expected in a good result a ter nerve trans er?
45 degrees.

What options are available or restoration o elbow exion in patients that present late (> 12 months a ter
injury)?
1. Free unctioning muscle trans er
2. endon trans er o available, expendable muscles
3. Steindler f exorplasty (transposition o f exor-pronator origin to anterior humerus)
4. Pectoralis major trans er
5. Latissimus dorsi trans er
6. riceps trans er
OBSTETRICAL BRACHIAL PLEXUS INJURY

What are the risk actors or obstetrical brachial plexus palsy?
1. Increased birth weight
2. Vertex presentation
3. Births that require instrumentation or delivery
4. Shoulder dystocia

What are causes or obstetric brachial plexus injury (birth palsy)?
raction injury secondary to:
Fetal malposition
Cephalopelvic disproportion
Forceps use

What are the three distributions observed in obstetric brachial plexus palsy?
1. Erb palsy
2. Panplexus palsy
3. Klumpke palsy

What nerve roots are involved in Erb palsy?
C5-6—upper roots.

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What nerve roots are involved in Klumpke palsy?
C5- 1—lower roots.

What is considered an indication or surgery in obstetric brachial plexus injuries?
Absent biceps recovery at age 3 months.

What does the Mallet classi cation assess?
Upper extremity unction

Which root levels are more likely to be af ected by root avulsions?
Lower levels C8, 1.

What is the mainstay or treatment o children with partial lesions?
1. Conservative treatment
2. ROM exercises
3. Prevention o contractures

What is the typical pattern o contracture o the shoulder in children with brachial plexus birth palsy?
Internal rotation.
Adduction.

What is a common complication due to the internal rotation contracture in children with brachial plexus
birth palsy?
Posterior shoulder dislocation.

What nonsurgical treatment can be used to treat early posterior shoulder dislocation due to internal rotation
contracture?
Closed reduction and Botulinum toxin A injection into the shoulder internal rotators.

What tendon trans er can be used to improve external rotation o the shoulder and prevent the development
o internal rotation contracture?
rans er o latissimus dorsi and teres major to the humeral greater tuberosity.

What de ormity o the elbow will requently develop in children with obstetric brachial plexus palsy?
Posterior radial head dislocation. ypically by age 5 to 8 years.

What is a typical nding in the orearm o children with obstetric palsy?
Supination contracture.

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REFERENCES
Bertelli JA, Ghizoni MF. Brachial plexus avulsion injury repairs with nerve trans ers and nerve gra ts directly implanted into the spinal
cord yield partial recovery o shoulder and elbow movements. Neurosurgery. 2003;52:1385–1390.
Bertelli JA, Ghizoni MF. T e possible role o regenerating axons in pain persistence a ter brachial plexus gra ting. Microsurgery.
2010;30(7):532–536.
Brandt KE, Mackinnon SE. A technique or maximizing biceps recovery in brachial plexus reconstruction. J Hand Surg Am.
1993;18(4):726–733.
Brunelli G, Monini L. Direct muscular neurotization. J Hand Surg Am. 1985;10:993–997.
Carvalho GA, Nikkhah G, Matthies C, Penkert G, Samii M. Diagnosis o root avulsions in traumatic brachial plexus injuries: value o
computerized tomography myelography and magnetic resonance imaging. J Neurosurg. 1997;86:69–76.
Coulet B, Boretto JG, Lazerges C, Chammas M. A comparison o intercostal and partial ulnar nerve trans ers in restoring elbow f exion
ollowing upper brachial plexus injury (C5-C6+ /−C7). J Hand Surg Am. 2010;35(8):1297–1303.
Doi K, Muramatsu K, Hattori Y, et al. Restoration o prehension with the double ree muscle technique ollowing complete avulsion o
the brachial plexus. indications and long-term results. J Bone Joint Surg Am. 2000;82(2):652–666.
Ezaki M, Malungpaishrope K, Harrison RJ, et al. OnabotulinumtoxinA injection as an adjunct in the treatment o posterior shoulder
subluxation in neonatal brachial plexus palsy. J Bone Joint Surg Am. 2010;92(12):2171–2177.
Narakas AO. T e treatment o brachial plexus injuries. Int Orthop. 1985;9:29–36.
Oberlin C, Beal D, Leechavengvongs S, Salon A, Dauge MC, Sarcy JJ. Nerve trans er to biceps muscle using a part o ulnar nerve or
C5-C6 avulsion o the brachial plexus: anatomical study and report o our cases. J Hand Surg Am. 1994;19:232–237.
Ruch DS, Friedman AH, Nunley JA. T e restoration o elbow f exion with intercostal nerve trans ers. Clin Orthop Relat Res.
1995;314:95–103.
erzis JK, Kostopoulos E. Our experience with secondary reconstruction o external rotation in obstetrical brachial plexus palsy. Plast
Reconstr Surg. 2010;126(3):951–963.
ung H, Mackinnon SE. Nerve trans ers: indications, techniques, and outcomes. J Hand Surg Am. 2010;35(2):332–341.
Uerpairojkit C, Leechavengvongs S, Witoonchart K, Malungpaishorpe K, Raksakulkiat R. Nerve trans er to serratus anterior muscle
using the thoracodorsal nerve or winged scapula in C5 and C6 brachial plexus root avulsions. J Hand Surg Am. 2009;34(1):74–78.

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381
Pieter G.L. Koolen, MD,
John B. Hijjawi, MD, FACS, and
Samuel J. Lin, MD, MBA, FACS
PRINCIPLES

What should the patient’s joints be assessed or prior to considering a tendon trans er?
1. Mobility
2. Contracture

What is a prerequisite or success ul outcome o tendon trans ers?
Flexibility o the joint to be moved by trans erred tendons.

What are the goals o preoperative therapy?
Maintain passive mobility.
Prevent joint contractures.

What actors need to be considered when selecting a donor muscle or tendon trans er?
1. Adequate strength
2. endon excursion
3. Straight line o pull
4. Synergism o action between the donor and recipient muscles
5. Expendable donor
6. issue equilibrium

What geometric eature correlates with the strength o a muscle?
Cross-sectional area o the muscle.
Tendon Transfers
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What does the work capacity o a muscle correlate with?
Muscle volume.

What does muscle excursion correlate with?
Muscle- ber length.

How much tendon excursion can be ound in wrist exors and extensors?
30 mm.

What is the amplitude o tendon excursion or nger extensors and exors, respectively?
1. 50 mm
2. 70 mm
T us, when wrist tendons are used to restore nger unction, there is usually incomplete correction.

How can the ef ective amplitude o tendon excursion be increased?
1. Increasing the number o joints the muscle tendon unit crosses.
2. Dissection o the muscle rom its surrounding ascial attachments.
RADIAL NERVE

What is the most signi cant limb dys unction a ter radial nerve palsy?
Inability to extend the wrist and stabilization or all other hand activities.

What is the ef ect o restoring active wrist extension on grip strength?
Grip strength will increase three to ve old.

What is the advantage o maintaining active wrist motion?
enodesis e ect.

What is the tenodesis ef ect?
Finger extension with wrist exion. ry this on yoursel .

What are the indications or tendon trans er?
Insuf cient recovery o unction a ter nerve injury that has been observed or an appropriate length o time.

What is o ten considered as an early tendon trans er within weeks a ter nerve injury?
Single tendon or wrist extension (e.g., pronator teres to ECRB) as an internal splint.

What is the advantage o the early tendon trans er?
Facilitates power grip by wrist extension, and nger extension through tenodesis e ect.

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What is the pre erred timing or the delayed tendon trans ers?
6 to 18 months.

In general what are the available donor muscles or tendon trans ers in radial nerve palsy?
All extrinsic median and ulnar nerve innervated muscles.

What muscle tendon trans ers are included in the Brand trans er or radial nerve palsy?
1. P to ECRB
2. FCR to EDC
3. PL to EPL
T us, wrist, nger, and thumb extension, the critical de cits in radial nerve palsy, are restored.

What is the Boyes tendon trans er?
A tendon trans er or radial nerve palsy includes:
1. P to ECRB
2. FDS III to EDC
3. FDS IV to EIP and EPL
4. FCR to APL and EPB

What is the advantage o the Boyes trans er?
It can be used in patients who do not have a palmaris longus.

What is the disadvantage o the FDS III and IV tendon trans er?
Bowing o the donor digits.

What tendon trans ers are included in the FCU trans er or radial nerve palsy?
1. P to ECRB
2. FCU to EDC
3. PL to EPL

What is the pre erred tendon trans er to restore active wrist extension in a radial nerve palsy?
P to ECRB.

What muscle tendon trans ers can be used or restoration o MPJ extension?
1. FCR to EDC
2. FCU to EDC
3. FDS III to EDC

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What is the theoretical advantage o the FDS III to EDC trans er in restoration or MPJ extension?
1. Straight line o pull
2. Expendable donor
3. Suf cient strength
4. Suf cient excursion
5. Synergism

What are potential disadvantages o the FCU to ECRB trans er?
Weakness o wrist exion with wrist radial deviation de ormity and unnecessary strength o wrist extension.

What is the primary choice or restoration o nger extension?
FCR to EDC trans er.

Why does the FDS III trans er not inter ere with the exor power o the other three FDS muscles?
Because the FDS III has a separate muscle belly.

What are the two unctions o the unctioning EPL?
1. T umb IP extension
2. T umb adduction

How can the PL to EPL trans er restore thumb abduction in addition to thumb extension?
Rerouting the EPL rom the third dorsal compartment and allowing it to lie along the rst dorsal compartment
will convert its adduction moment into an abduction moment.

Which anatomic route is used or the FDS III to EDC tendon trans er?
FDS III tendon is rerouted through a large window in the interosseous membrane o the orearm.

What is the position o immobilization a ter tendon trans ers or wrist extension, nger extension, and
thumb extension?
1. 90-degree elbow exion
2. Neutral orearm rotation
3. 45-degree wrist extension
4. Full extension o MPJ
5. T umb abduction and ull extension o IP and MPJ

When should dynamic splinting be initiated?
A ter 3 weeks o initial immobilization.

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What does the dynamic splint a ter tendon trans er or radial nerve palsy entail?
1. Dynamic extension outrigger
2. 30-degree wrist extension
3. MP exion block at 30 degrees increased at weekly intervals
4. Active ROM initiated at 5 weeks postoperation

How is extensor lag at the MPJ postoperatively addressed?
1. Delay o passive ROM and dynamic splinting
2. Extension splinting
MEDIAN NERVE

What is the major de cit associated with low median nerve palsy?
Loss o thumb opposition and sensation o palmar sur aces o thumb, index, long, and radial hal o ring nger.

What muscles acilitate thumb opposition?
1. Abductor pollicis brevis
2. Opponens pollicis
3. Super cial head o exor pollicis brevis

What are conditions leading to loss o thumb opposition?
1. Median nerve laceration
2. Chronic carpal tunnel syndrome
3. Congenital de ciency o thenar musculature (thumb hypoplasia)
4. Polyneuropathy
5. T enar trauma

What trapeziometacarpal joint motions constitute thumb opposition?
1. Abduction
2. Flexion
3. Pronation—opposes the volar sur aces o the thumb and ngers

What explains maintained ability o thumb opposition a ter complete median nerve laceration at the wrist?
Variable ulnar nerve innervation o the super cial head o the exor pollicis brevis.

What are our reliable options or opponensplasty?
1. EIP
2. ADM (Huber)
3. Palmaris longus (Camitz)
4. FDS o the ring nger

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What are the landmarks o the vector line o pull or the most common tendon trans ers to restore thumb
opposition?
1. Os pisi orme
2. APB insertion

What is the most common tendon trans er used or low median nerve palsy?
EIP to APB trans er.

Where can the EIP tendon be located at the dorsum o the second MPJ?
Ulnar to the EDC tendon to the index.

How is proper tensioning o the opponensplasty assessed?
1. Full thumb adduction with passive wrist exion.
2. Appropriate thumb opposition with passive wrist extension.

What is the Huber trans er?
Abductor digiti minimi trans er or thumb opposition.

What is the classic indication or the Huber trans er?
Congenital hypoplastic thumb.

What is the advantage o the Huber trans er?
Cosmesis—the muscle bulk restores the hypoplastic thenar eminence.

What is the disadvantage o the Huber trans er in thumb hypoplasia?
Insuf cient tendon or thumb MCP reconstruction. T e long or ring nger FDS trans er does not have this
limitation although it lacks bulk.

What is the position o immobilization a ter opponensplasty?
1. T umb spica with opposition o thumb.
2. Slight wrist extension or EIP and ADM trans ers.
3. Slight wrist exion or FDS and PL trans ers.

What additional de cits distinguish the high rom the low median nerve palsy?
1. Inability to bend the thumb IP joint (FPL).
2. Inability to bend the index and long nger (FDS, FDP).

What progressive de ormity may develop a ter chronic high median nerve palsy?
Swan neck de ormity o the small and ring nger (absent FDS unction).

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How is the variability in loss o nger exion particularly o the long nger explained?
Variable innervation o the FDP o the long nger by the ulnar nerve.

What is the pre erred procedure to restore a normal nger exion cascade in high median nerve palsy?
Side-to-side tenodesis o long and index nger FDP to the ring and small nger FDP.

What donor muscle is most commonly used or restoration o FPL unction?
Brachioradialis.

How can the available excursion o the brachioradialis muscle be maximized?
1. Mobilization o the muscle.
2. Freeing it rom its ascial envelope up to the proximal orearm.
3. Excursion up to 5 cm can be accomplished.

What is the appropriate tension o the BR to FPL trans er?
1. Full IP extension with 20 degrees o wrist exion.
2. Adequate IP exion with wrist extension.

How can lack o active orearm rotation be addressed?
Rerouting o the biceps tendon insertion to the lateral aspect o the proximal radius.

What is the signi cance o sensory de cits?
1. Limit the use ulness o tendon trans ers.
2. Every e ort to restore sensation should be made prior to tendon trans er via:

i. Nerve repair/gra ting

ii. Nerve decompression

iii. Nerve trans ers

iv. Neurovascular island aps
ULNAR NERVE

What is low ulnar nerve palsy as opposed to high ulnar nerve palsy?
Lesion o ulnar nerve distal to innervation o FDP.

Which ngers will typically be clawing in low ulnar nerve palsy?
Small and ring ngers.

What is the reason or the claw de ormity?
Absent intrinsic muscle unction (remember that the ulnar innervated lumbricals extend the ring and small nger
PIP joints).

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Why do index and long nger typically not develop clawing in isolated ulnar nerve palsy?
Persistent unction o the radial two lumbrical muscles that are median innervated.

What does the claw de ormity involve?
1. Hyperextension o the MPJ
2. Inability to ully extend the PIP and DIP

Which type o ulnar nerve palsy will demonstrate more signi cant clawing?
1. Low ulnar nerve palsy.
2. Persistent unction o ulnar two FDP in low ulnar nerve palsy will produce de orming orce on the PIP joints.
T ese FDPs are not unctional in high ulnar nerve palsy.

What eponym describes the clawing o ring and small ngers?
Duchenne sign.

What is the Bouvier maneuver?
Blocking o MP hyperextension that will allow the EDC to ully extend the PIP and DIP.

What is the Wartenberg sign?
Inability to adduct the extended small nger.

What is the de orming orce or the Wartenberg sign?
Unopposed pull o the radially innervated EDQ (absent ourth dorsal IO muscle).

What is the Froment sign?
Hyper exion o the thumb IP joint with key pinch to compensate or the de cient thumb adductor.

What is the Jeanne sign?
Hyperextension o the MPJ o the thumb with attempted key pinch.

What tendon trans ers are available to restore thumb adduction?
1. ECRB to thumb adductor via intercalated tendon gra t
2. FDS o long or ring to thumb adductor insertion

Which route is used or the ECRB trans er or thumb adduction?
1. Subcutaneously extracompartmental
2. Around the second or third metacarpal neck
3. Volar to adductor pollicis
4. Deep to exor tendon and neurovascular structures

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What additional unction can be restored to improve the power o key pinch?
Index nger abduction.

What trans ers are available or restoration o index nger abduction?
Accessory slip o abductor pollicis longus or EIP (EIP trans er may lead to unacceptable amount o abduction).

What are the general two types o tendon trans ers that are per ormed or correction o claw de ormity?
1. Static trans er
2. Dynamic trans er

What is involved in a static anti-claw trans er?
enodesis o the lateral bands with a tendon gra t around the deep transverse metacarpal ligaments providing an
internal splint that prevents hyperextension o the MPJ.

What does the Zancolli lasso procedure ef ectively treat?
Claw de ormity.

What does the Zancolli Lasso procedure consist o ?
1. FDS is looped back to itsel around the A1 pulley.
2. Providing a dynamic exion moment at the MPJ.

What tendon trans er to correct claw de ormity originates rom the dorsal side o the wrist?
T e Bunnell–Stiles tendon trans er.

What are the steps o the Bunnell–Stiles tendon trans er?
1. ECRL transected distally and rerouted dorsally.
2. wo slips o palmaris longus or plantaris gra t extension sewn into the ECRL.
3. endons rerouted through the lumbrical canal (volar to the deep transverse metacarpal ligament).
4. Gra t tails attached to radial lateral bands o the ring and small ngers or alternatively to radial side o proximal
phalanx (see next question).

What de ormity can occur a ter the Bunnell–Stiles trans er to the radial lateral bands?
Swan neck de ormity.

How can the development o swan neck de ormity a ter the Bunnell–Stiles tendon trans er prevented?
rans er o the tendon to the proximal phalanx rather than the lateral band.

What patient actors lead to a higher likelihood o swan neck de ormity a ter the Bunnell–Stiles trans er into
the lateral bands?
PIP joint hyperextensibility.

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What additional unction is lost in a high ulnar nerve palsy?
Absent small and ring nger FDP.

What tendon trans er reliably restores ring and small nger DIP joint exion?
Side-to-side trans er o small and ring nger FDP to median innervated index and long nger FDP tendon.
COMBINED PALSIES

What is the most common mechanism or combined nerve palsies?
Lacerations—particularly at the wrist.

What is the most common combined nerve palsy?
Low median-ulnar nerve palsy.

What are the requirements or restoration o wrist and hand unction in low median and ulnar nerve palsy?
1. Improve key pinch.
2. T umb abduction (to improve opposition).
3. ip pinch (increase index strength in pinch which has been compromised by rst dorsal interosseous palsy).
4. Power nger exion with coordinated MP and PIP motion.
5. Sensibility in the distribution involved in key pinch.

What is the pre erred thumb opposition trans er in combined median-ulnar nerve palsy?
1. EIP trans er
2. Second choice: PL, FDS

What muscles are pre erred or restoration o thumb adduction?
1. ECRB
2. Long nger FDS

How can the last two trans ers use the FDS i these are or combined ulnar-median nerve palsies?
Because they are or low (wrist level) combined palsies.

What procedures can help to improve thumb-index tip pinch?
1. T umb IP usion.
2. rans er o APL with gra t extension to rst dorsal interosseous.

What type o procedure will help with integration o MP and IP joint motion?
Intrinsic trans ers (e.g., Bunnell–Stiles).

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REFERENCES
Anderson GA, Lee V, Sundararaj GD. Opponensplasty by extensor indicis and exor digitorum super cialis tendon trans er. J Hand
Surg Br. 1992;17:611–614.
Friden J, Lieber RL. endon trans er surgery: clinical implications o experimental studies. Clin Orthop Relat Res. 2002;(403 Suppl):
S163–S170.
Gold arb CA, Stern PJ. Low ulnar nerve palsy. J Am Soc Surg Hand. 2003;3:14–26.
Green DP. Radial nerve palsy. In Green DP, Hotchkiss RN, Pederson WC, eds. Green’s Operative Hand Surgery. Vol 2. 4th ed. New York,
NY: Churchill Livingstone; 1999:1481–1496.
Krishnan KG, Schackert G. An analysis o results a ter selective tendon trans ers through the interosseous membrane to provide selective
nger and thumb extension in chronic irreparable radial nerve lesions. J Hand Surg Am. 2008;33(2):223–231.
Mc Carroll HR. endon trans ers. In: Light R, ed. Hand Surgery Update. 2nd ed. Rosemont, IL: American Academy o Orthopaedic
Surgeons; 1999:161–169.
Omer G. Combined nerve palsies. In: Green DP, Hotchkiss RN, Pederson WC, eds. Green’s Operative Hand Surgery. Vol 2. 4th ed.
New York, NY: Churchill Livingstone; 1999:1542–1555.
Ratner JA, Peljovich A, Kozin SH. Update on tendon trans ers or peripheral nerve injuries. J Hand Surg Am. 2010;35(8):1371–1381.
Sammer DM, Chung KC. endon trans ers: part II. trans ers or ulnar nerve palsy and median nerve palsy. Plast Reconstr Surg. 2009;
124(3):212e–221e.

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393
Sanjeev Kakar, MD, MRCS and
Bassem T. Elhassan, MD

What is the carpal height ratio?
It is the distance de ned rom the base o the third metacarpal to the distal subchondral bone o the radius divided
by the length o the third metacarpal. T e normal ratio is 0.54 ± 0.03.

What are the main muscles primarily responsible or wrist motion?
T ey include the exor carpi radialis, exor carpi ulnaris, extensor carpi radialis longus and brevis, and extensor
carpi ulnaris (ECU).

What is the only muscle that inserts into the carpus?
Flexor carpi ulnaris attaches into the pisi orm.

How many degrees o reedom are there pertaining to wrist range o motion?
T ere are six degrees o reedom: exion, extension, radial deviation, ulnar deviation, pronation, and supination.

What is the intercalated segment within the wrist?
T e proximal row (scaphoid, lunate, and triquetrum) is the intercalated segment within the wrist. T e bones o
the proximal row are less tightly bound together than the distal row and there is approximately three times more
motion between the scaphoid and lunate compared to the lunotriquetral joint.

How does the position o the proximal row change with wrist range o motion?
During wrist exion, the bones o the proximal row go into exion and ulnar deviation whereas with wrist extension,
they go into extension and radial deviation. Similar motion is noted within the distal carpal row albeit with less
radial and ulnar deviation as noted with the proximal carpal row during wrist extension and exion, respectively.

What are the di erent regions within the scapholunate (SL) ligament called?
T ere are three regions that comprise the SL ligament: the dorsal, the membranous or proximal, and palmar
regions. In cadaveric studies, disruption o the dorsal SL ligament resulted in a signi cant change in the spatial
relationship between the scaphoid and lunate.
Wrist Kinematics
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What position does the scaphoid assume with disruption o the SL ligament?
T e scaphoid exes and pronates with respect to the radius whereas the lunate assumes an extended position. T is
is termed dorsal intercalated segment instability (DISI) o the lunate.

What structures need to be disturbed or the lunate to assume a volar intercalated segment instability (VISI)
position?
Disruption o the dorsal and palmar regions o the lunotriquetral ligament does not mani est with VISI static
instability. For VISI to be noted, disruption o the dorsal radiotriquetral or dorsal scaphotriquetral must also occur.

What is the normal orce transmission through the wrist?
In neutral position and neutral ulnar variance, approximately 80% to 85% o axial load is transmitted through the
radiocarpal joint and 15% to 20% through the ulnocarpal joint.

What are the components o the triangular f brocartilaginous complex ( FCC)?
T e FCC comprises an articular disc, super cial and deep dorsal and palmar radioulnar ligaments,
ulnotriquetral, ulnolunate, ulnocapitate ligaments, and the ECU within its subsheath.

What is the unction o the FCC?
T e primary responsibility o the FCC is to maintain stability o the distal radioulnar joint (DRUJ). In addition,
it plays an important role in orce transmission across the wrist with studies showing that removal o two-thirds or
more o complex having an ef ect on orce transmission.

What is the stable bone o the DRUJ?
T e ulnar is the xed bone o the DRUJ around which the radius rotates.

What are the dynamic and static stabilizers o the DRUJ?
T e dynamic stabilizers o the DRUJ include the ECU and pronator quadratus whereas the static restraints
include the DRUJ capsule, ulnotriquetral and ulnolunate ligaments, interosseous membrane, and FCC. In
terms o the latter, the primary stabilizers o the DRUJ are the palmar and dorsal radioulnar ligaments. T ey
originate rom the distal margins o the DRUJ and appear as thickenings at the junction o the FCC, DRUJ,
and ulnocarpal capsule. T e cartilaginous disc is located centrally between these ligaments. As the radioulnar
ligaments pass toward the ulna, they divide into a super cial limb, which inserts into the ulna styloid, and a deep
limb that attaches to the ovea. T ey remain in a relaxed position until terminal pronation and supination, thereby
permitting palmar and dorsal translation o the ulna head over several millimeters.

What is the name o the articular sur ace o the radius that articulates with the ulnar?
T e sigmoid notch. T e sigmoid notch has a radius o curvature that is greater than that o the ulnar head.
Increased stability to this articulation is provided by the DRUJ ligaments and palmar/dorsal brocartilaginous
projections rom the sigmoid notch.

What changes are seen in relation o the ulnar head to sigmoid notch o the radius during pronation and
supination?
In ull pronation, the ulnar head rests against the dorsal lip o the sigmoid notch. In supination, the ulnar head
rests against the palmar sur ace o the sigmoid notch.

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What position o the orearm reduces dorsal dislocation o the ulna with respect to the radius?
T ese dislocations are reduced with the orearm in a supinated position.

What is the eponym commonly given to ipsilateral radial head ractures and concomitant DRUJ injuries?
Essex-Lopresti lesions represent ligament injury at the distal DRUJ combined with elements o attenuation or
disruption o the interosseous membrane. Its importance is related to the observation that the radius can migrate
proximally i the radial head is excised and not replaced given disruption o its distal tether at the wrist.

What happens to orce transmission across the wrist with changes in ulnar length?
In patients with a short ulnar (ulnar negative variance), as o ten seen in Kienbock disease, there is a decrease in
orce transmission across the ulnar with corresponding increase across the radiocarpal joint.

What is the blood supply to the proximal pole o the scaphoid?
T e main blood supply is rom the radial artery and enters through small oramina in the dorsal ridge. Fractures
proximal to this area may result in avascular necrosis o the proximal pole.

Which extrinsic wrist ligament is elt to be the strongest support in the wrist?
T e radioscaphocapitate ligament is elt to be the most important ligament or wrist support.

As the wrist moves rom ulnar deviation to radial deviation, what happens to the scaphoid?
T e scaphoid moves rom an extended position into a palmar- exed position.

What are the major extrinsic ligaments o the dorsal wrist?
T e dorsal radiocarpal ligament and the dorsal intercarpal ligament are the major dorsal extrinsic wrist ligaments.

What does DISI stand or?
DISI stands or dorsal intercalary segment instability and is related to tears o the SL ligament.

What is the erry T omas sign?
T e erry T omas sign is an abnormal gap between the scaphoid and lunate that occurs in SL ligament tears. It is
named a ter the gap-toothed British comedian.

T e spilled tea-cup sign is seen in which carpal instability pattern?
T e spilled tea-cup sign is seen in volar intercalary segment instability (VISI).

What is meant by “progressive perilunate instability”?
Progressive perilunate instability is a progression o injury, beginning at the SL joint and progressing in severity to
total perilunate injury.

What is Stage I perilunate instability?
Stage I perilunate instability is scaphoid racture or a SL interosseous ligament tear.

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Plastic & Reconstructive Surgery Board Review

What is Stage II perilunate instability?
Stage II perilunate instability is a SL ligament injury with lunocapitate dislocation and a tear through the space o
Poirier.

What is Stage III perilunate instability?
Stage III perilunate instability is associated with a lunotriquetral ligament tear or triquetrum racture.

What is Stage IV perilunate instability?
Stage IV perilunate instability is a lunate dislocation.

How does one di erentiate a perilunate dislocation rom a lunate dislocation?
In a perilunate dislocation, the lunate remains seated in the lunate ossa o the radius and all other carpal bones
are sitting dorsal to their typical position. In a lunate dislocation the lunate is dislocated palmarly into the carpal
tunnel and the other carpal bones are in their typical location.

What is the most common racture in carpal bones?
T e scaphoid is the most commonly ractured carpal bone.

What di erentiates a perilunate dislocation and a trans-scaphoid perilunate dislocation?
In a trans-scaphoid perilunate dislocation, the scaphoid bone is ractured and the SL interosseous ligament
remains intact.

What radiographic lines in the wrist are used to help determine normal anatomy rom certain pathologic
states including lunate and perilunate dislocations?
Gilula lines show continuity o the radiocarpal and midcarpal joints.

What is the scaphoid shi t test?
T e scaphoid shi t test is a test looking or SL ligament injury. With the wrist held in ulnar deviation, and the
examiner’s thumb holding pressure on the scaphoid tubercle, the wrist is passively brought into radial deviation. In
patients with SL dissociation, the scaphoid, being held extended by the thumb, shi ts dorsally causing pain and a
clunk as the scaphoid moves back into the scaphoid ossa.

What is the current treatment or the acute static SL dissociation?
Most surgeons are currently per orming SL ligament repair, supplemented by some orm o dorsal wrist
capsulodesis.

What is the current treatment or lunate and perilunate dislocations?
T e recommended treatment is ORIF with both volar capsular repair and dorsal ligament repair.

What is the current recommendation or proximal pole ractures o the scaphoid?
Owing to the high rate o nonunion ORIF with screw xation, using a dorsal approach is recommended.

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What is ulnar translocation o carpus?
In individuals where there is tearing o the radioscaphocapitate and long radiolunate ligaments, the carpus will
sometimes migrate ulnarly and volarly ollowing the slope o the radius. ranslocation can also occur in certain
rheumatologic conditions o the wrist.

Which ractures o the radius are requently associated with SL ligament tears?
Intra-articular ractures o the radius that are in the vicinity o the SL ligament are requently associated with SL
ligament tears.

What is the appropriate initial treatment or an individual who a ter a all onto an outstretched hand has
pain in the snu box and negative radiographs?
T e appropriate initial treatment is short arm thumb spica splinting or casting with ollow-up in 2 weeks.
Continued pain in the snuf box in the absence o x-ray ndings required additional studies to rule out scaphoid
racture (bone scan/MRI/C scan).

Scaphoid ractures in which location have the best prognosis?
Fractures o the distal pole o the scaphoid have the best prognosis. T ese ractures can be managed by short arm
thumb spica splint or short arm thumb spica cast.

What is the second most commonly ractured carpal bone?
T e triquetrum is the second most commonly ractured carpal bone. Most triquetral ractures are dorsal marginal
ractures.

What is the most common mechanism or ractures o the hook o the hamate?
Most ractures o the hook o the hamate occur as a result o a direct blow.

I one suspects a hook o the hamate racture clinically, what is the best conf rmatory study?
T e best con rmatory or hook o hamate ractures study is a C scan.

In a patient with a hook o hamate nonunion, what is the best treatment?
T e best treatment or a hook o hamate nonunion is excision o the hook o the hamate.

What imaging modality is used to stage Kienbock disease?
Plain radiographs are used to stage Kienbock disease. MRI is help ul in diagnosing Kienbock disease.

What are the x-ray f ndings in Stage I Kienbock disease?
X-rays are either normal or you may see linear ractures in the lunate.

What are the x-ray f ndings in Stage II Kienbock disease?
T e lunate shows increased density in Stage II Kienbock disease.

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Plastic & Reconstructive Surgery Board Review

What are the x-ray f ndings in Stage III Kienbock disease?
T e lunate shows collapse and/or ragmentation in Stage III Kienbock disease.

What are the x-ray f ndings in Stage IV Kienbock disease?
Arthritis is present in Stage IV Kienbock disease.

What x-ray f nding o the bones o the orearm is associated with Kienbock disease?
Ulnar negative variance has been associated with Kienbock disease.

What are the measurements o carpal height used or?
Measurements o carpal height are used as a means o diagnosing SL dissociation. T e normal ratio is 0.54.
Smaller ratios are indicative o the carpal collapse seen in SL dissociation.

What does the term SLAC wrist re er to?
T e term SLAC re ers to SL advanced collapse.

What is the SLAC procedure and what must be normal to consider this procedure?
T e SLAC procedure is a our-corner (C-L-H- ) usion with excision o the scaphoid and radial styloidectomy.
T e lunate ossa and proximal articular sur ace o the lunate must be intact to consider this procedure.

What radiographic f ndings are usually present in patients with a lunatotriquetral ligament tear?
Plain radiographs are usually normal in patients with isolated lunatotriquetral ligament tears. VISI de ormities can
be seen in more complex L ligament injuries.

What are the components o the triangular f brocartilage complex?
T e components are the FC proper, the ulnar collateral ligament, the ECU subsheath, the meniscus homologue,
the ulnolunate and ulnotriquetral ligaments, and the dorsal and palmar radioulnar ligaments.

What parts o the SL ligament are responsible or the biomechanical behavior o the joint?
T e thick dorsal and volar portions o the ligament are 3 mm thick and give strength and integrity to the joint.

What is a Geisler Stage I SL instability?
T is is where attenuation or hemorrhage o the SL ligament can be seen rom the radiocarpal joint. T e SL joint
appears to be congruent when viewed rom the midcarpal portal.

What is a Geisler Stage II SL instability?
Similar ndings are noted within the radiocarpal joint as seen with Geisler Stage I. T e SL joint appears to be
incongruent when viewed rom the midcarpal portal and a gap less than the width o a probe may be present
between the scaphoid and the lunate.

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399

What is a Geisler Stage III instability?
Incongruency/step-of between the scaphoid and the lunate can be seen rom both the radiocarpal and midcarpal
spaces and the probe can be passed between the carpal bones.

What is a Geisler Stage IV instability?
Geisler Stage IV instability occurs when the arthroscope (2.7 mm) can be passed through the midcarpal joint to
the radiocarpal joint. T is is also known as the drive-through sign.

What percent o arthrograms will show a SL ligament tear in an asymptomatic patient?
27% o arthrograms will show an SL tear in asymptomatic patients.

What is the reported accuracy o MR arthrogram or determining SL ligament tears?
T e reported accuracy o MR arthrography is 95%.

What is the def nitive diagnostic test or intercarpal pathology?
Wrist arthroscopy is the de nitive test or intercarpal pathology.

What is the average radial inclination o the distal radius?
22 degrees.

What is the average volar tilt o the distal radius?
11 degrees.

How many millimeters o intra-articular displacement within a distal radius racture is considered to be
acceptable with nonoperative management?
Up to 1 mm o displacement.

What is a “Colles” racture?
T is is a distal radius racture with dorsal angulation, dorsal comminution, dorsal displacement, and radial
shortening.

What is a “Smith” racture?
T is is a distal radius racture with apex dorsal angulation with volar subluxation o the carpus (this is opposite
to a Colles racture that has apex volar angulation with dorsal displacement o the carpus). T is is an important
recognition as the mold placed within the cast or each racture dif ers.

What is a “Barton” racture?
T is is an intra-articular distal radius racture.

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Plastic & Reconstructive Surgery Board Review

Why is the assessment o median nerve unction important in the examination o patients with a distal
radius racture?
Patients with acute distal radius ractures can experience paresthesias within the median nerve distribution
secondary to an acute carpal tunnel syndrome. A ter racture reduction, these symptoms should improve and
nerve compression can be treated with observation alone. Should they progress, an emergent release o the carpal
tunnel is indicated.

What is the most common tendon susceptible to spontaneous rupture in undisplaced distal radius racture?
T e EPL tendon is susceptible to rupture and is more likely in undisplaced compared to displaced distal radius
ractures. Postulated theories or the etiology include tendon attrition and impaired blood supply to the tendon.

What is the most common tendon rupture seen with volar plating o distal radius racture?
T e FPL tendon is susceptible to rupture as it runs over the volar lip o the distal radius. For this reason, it is o
vital importance that the plate NO be placed to distal.
REFERENCES
Andrews JG, Youm Y. A biomechanical investigation o wrist kinematics. J Biomech. 1979:12:83–93.
Adol sson L. Arthroscopy or the diagnosis o post-traumatic wrist pain. J Hand Surg Am. 1992;17:46–50.
Barber H. T e interosseous arterial anatomy o the adult human carpus. Orthopedics. 1972;5:1–19.
Beckenbaugh RD. Accurate evaluation and management o the pain ul wrist ollowing injury. An approach to carpal instability. Orthop
Clin North Am. 1984;15:289–306.
Berger RA, Crowninschield RD, Flatt AE. T e three dimensional rotational behaviours o the carpal bones. Clin Orthop Relat Res.
1982;167:303–310.
Berger RA, Garcia-Elias M. General anatomy o the wrist. In: An KN, Berger RA, Cooney WP, eds. Biomechanics of the Wrist Joint.
New York, NY: Springer; 1991.
Berger RA. T e gross and histologic anatomy o the scapholunate interosseous ligament. J Hand Surg Am. 1996;21:170–178.
De Lange ALH. A kinematic study of the human wrist joint. the Netherlands: Doctoral thesis; 1987.
Dobyns JH, Linscheid RL, Chao EYS, et al. raumatic instability o the wrist. AAOS Instructional Course Lectures. 1975;24:182–199.
Fisk GR. Carpal instability and the ractured scaphoid. Ann R Coll Surg Engl. 1970;46:63–76.
Fisk GR. T e wrist. J Bone Joint Surg. 1984;66:396–407.
Garcia-Elias M, Dobyns JH, Cooney WP, Linscheid RL. raumatic axial dislocations o the carpus. J Hand Surg Am. 1989;14:446–456.
Garcia-Elias M, Horii E, Berger RA. Individual carpal bone motion. In: An KN, Berger RA, Cooney WP, eds. Biomechanics of the Wrist
Joint. New York, NY: Springer; 1991.
Gilula LA, Destout JM, Weeks PM, Young LV, Wray RC. Roentgenographic diagnosis o the pain ul wrist. Clin Orthop Relat Res.
1984;187:52–64.
Green DP, O’Brien E . Classi cation and management o carpal dislocations. J Bone Joint Surg. 1980;149:55–72.
Horii E, Garcia-Elias M, An KN, et al. A kinematic study o lunotriquetral dissociations. J Hand Surg Am. 1991:16:355–362.
Johnson RP. T e acutely injured wrist and its residuals. Clin Orthop Relate Res. 1980;149:33–44.
Kihara H, Short WH, Werner FW, Fortino MD, Palmer AK. T e stabilizing mechanism o the distal radioulnar joint during pronation
and supination. J Hand Surg Am. 1995;20(6):930–936.
Kirschenbaum D, Sieler S, Solonick D, Loeb DM, Cody RP. Arthrography o the wrist. assessment o the integrity o the ligaments in
young asymptomatic adults. J Bone Joint Surg Am. 1995;77:1207–1209.
Lavernia CJ, Cohen MS, aleisnik J. reatment o scapholunate dissociation by ligamentous repair and capsulodesis. J Hand Surg Am.
1992;17:354–359.

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Lichtman DM, Schneider JR, Swaf ord AR, Mack GR. Ulnar midcarpal instability—clinical and laboratory analysis. J Hand Surg Am.
1981;6:515–523.
Linscheid RL, Dobyns JH. T e uni ed concept o carpal injuries. Ann Chir Main. 1984;3:35–42.
Lynched RL, Dobbins JH, Beabout JW, Bryan RS. raumatic instability o the wrist. J Bone Joint Surg. 1972;54:1612–1632.
May eld JK, Johnson RP, Kilcoyne RK. Carpal dislocations: pathomechanics and progressive perilunar instability. J Hand Surg Am.
1980;5:226–241.
Moneim MS. Management o greater arc carpal ractures. Hand Clin. 1988;4:457–467.
Panagis JS, Gelberman RH, aleisnik J, Baumgaertner M. T e arterial anatomy o the human carpus. Part II: the interosseous vascularity.
J Hand Surg Am. 1983;8:375–382.
Palmer AK, Werner FW, Glisson RR, Murphy DJ. Partial excision o the triangular brocartilage complex. J Hand Surg Am.
1988;13:391–394.
Ruby LK, Cooney WP 3rd, An KN, Linscheid RL, Chao EY. Relative motion o selected carpal bones: a kinematic analysis o the
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Schuind F, An KN, Berglund L, et al. T e distal radioulnar ligaments: a biomechanical study. J Hand Surg Am. 1991;16(6):1106–1114.
Smith DK, An KN, Cooney WP 3rd, Linscheid RL, Chao EY. Ef ects o a scaphoid waist osteotomy on carpal kinematics. J Orthop
Res. 1989;7:590–598.
Smith DK, An KN, Cooney WP 3rd, Linscheid RL, Chao EY. T e ef ects o simulated unstable scaphoid ractures on carpal motion.
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Watson HK, Ballet FL. T e SLAC wrist: scapholunate advanced collapse pattern o degenerative arthritis. J Hand Surg Am. 1984;9:358–
365.
Wiedrich A. T e use o suture anchors in the hand and wrist. Oper Tech Plast Reconstr Surg. 1997;4:42–48.
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403
Sarosh N. Zafar, MD and
Scott L. Hansen, MD, FACS
DIGITAL REPLANTATION

What is the goal o digital replantation?
Equivalent or improved unction when compared to revision amputation and prosthesis.

What are the current indications or digital replantation?
• T umb
• Multiple digits
• Single digit distal to sublimis
• Hand at the wrist or orearm (sharp amputation)
• Any level amputation in a child

What is the appropriate preoperative workup or a patient with an amputated digit?
• Evaluate and stabilize the patient using A LS protocol.
• Do not complete partial amputations until ully examined in operating room.
• Wrap amputated part in moist gauze and place in plastic bag, then place on ice. Avoid direct contact with ice
which can result in irreversible damage to microvascular system.
• Administer intravenous antibiotics, and tetanus prophylaxis.
• Radiographs o the involved hand and the amputated part.
• Appropriate preoperative counseling and consent (include possible nerve/vein/skin gra t as well as possible
amputation).
Replantation
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What is the order or a single digit replant?
BEFANV:
• Bone
• Extensors
• Flexors
• Arteries
• Nerves
• Veins

What is the order or multiple digit replantations—digit by digit or structure by structure?
Structure by structure, systemically repairing as above.

What are the potential advantages to skeletal shortening in digital replantation?
• May enable more secure bone xation
• May minimize the need or vessel or nerve gra ting

What are the options or skeletal stabilization in digit replantation?
• Kirschner wires
• 90–90 wiring
• Miniplates and screw
• Intramedullary bone pegs

What are the unctional de cits associated with ray amputation o the index nger?
Loss o power grip and key pinch.

What is the lumbrical plus de ormity?
T e FDP tendon and lumbrical muscle migrate proximally a ter division o the tendon in trauma. With exion,
tension is exerted on the lumbrical via the radial lateral band causing paradoxical extension o the PIP during
exion o the MP joint.

reatment?
Division o the lumbrical insertion.

What is the most common cause o digital replantation ailure?
Arterial insu ciency.

What is the treatment o arterial insu ciency a ter digital replantation?
1. I any concern about arterial patency RE URN to OR
2. Loosen dressings
3. Heparin
4. Anti-vasospastic medications (T orazine)
5. Sympathetic blocks

CHAPTER 43 Replantation
405

What is the treatment o venous congestion a ter digital replantation?
1. Removal o dressings
2. Leech therapy
3. Heparin
4. Nail bed bleeding with heparin-soaked sponges
5. Revision o the venous anastomosis

Which tissue is most sensitive to warm ischemia?
Skeletal muscle.

What is the maximal cold ischemia time reported or digital replantation?
30 to 40 hours.

When should prophylactic asciotomies be per ormed in upper extremity replantation?
With any replantation proximal to the wrist prophylactic asciotomies should be per ormed because o the
increased amount o skeletal muscle present.

What is the quadriga e ect?
Weakness in exion o ngers secondary to excess pull o one FDP tendon o the amputated nger.

What is the maximum nerve gap or use o a neural tube (PGA)?
2.5 cm.

What nerves are available or use as donors or nerve gra ting?
• Posterior interosseous nerve
• Sural nerve
• Super cial radial nerve
• Super cial peroneal nerve

What is the treatment o choice or a tip amputation through the nail bed without bone exposure?
Local dressing changes (i.e., healing by secondary intention).

What is a good option or a ailed thumb replantation at the MCP level?
Revision amputation ollowed by toe-to-thumb trans er at a later date.

What donor vessel is the toe-to-thumb trans er based on?
First dorsal metatarsal artery rom dorsalis pedis artery or plantar digital artery rom lateral plantar artery.

What is a good option or a thumb-tip amputation with exposed bone?
Moberg ap.

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Plastic & Reconstructive Surgery Board Review

How much advancement can be obtained rom a Moberg f ap?
1.5 cm.

What are contraindications to digital replantation?
• Severe concomitant injuries
• Severely crushed or mangled
• Multilevel amputations
• Signi cant comorbidities
• Prolonged warm ischemia time
• Mentally unstable/sel -mutilation
• Single nger proximal to FDS insertion

How many arteries and veins are needed or a digital replantation?
One artery and one vein (two are pre erred).

Is an artery only digital replantation possible?
Yes. Leeching and/or bleeding o the nail bed can be used to relieve venous congestion.

How many places can you nd a digital vein?
wo. Dorsal and volar.

What is the concern in avulsion amputation versus guillotine amputation?
Zone o injury is much greater in avulsion injuries.

What is the red stripe sign?
A red streak along the artery indicating severe intimal injury along the length o the vessel.

What is the best method or treating the zone o injury o an artery or vein in cases o crush or avulsion
injuries?
Resection o compromised vessel and vein gra ting.

Where can veins be reliably ound on the hand dorsum?
Proximal to each web space.

What vascular pattern exists in a nger that was crushed and has the appearance o venous congestion and
slow capillary re ll?
Loss o proper digital artery in ow, intact venous ow.

Eight months post digital replantation, what operation would you o er to the patient with minimal passive
or active ROM?
Extensor tenolysis and open capsulotomy.

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What operation would you o er or someone with good passive but minimal active ROM?
Flexor tenolysis.

What is the greatest danger in digital reoperation a ter replantation?
Injury to the neurovascular bundle embedded in scar.

What is f uorimetry?
A method o monitoring tissue per usion by injecting uorescein dye intravenously and using a uorometer to
quantitatively measure rise and all o uorescein in tissue.

What i there is a two to three old rise but no all in the numbers?
Sign o venous congestion.

What i the absolute number is very low and remains low, but the digit clinically looks viable?
T ick skin or heavily contaminated skin can alter the numbers.

When is the highest likelihood o a thrombotic event at the microanastomosis?
Within 24 to 48 hours o microanastomosis.

At the microanastomosis, what is the predominant layer on day 3?
Platelets.

On days 4 to 14?
Pseudointima.

On day 14 onward?
Intima.

One year postreplantation at the PIPJ level with severe arthritis or usion at the PIPJ. What surgery can you
o er the patient?
PIP joint arthroplasty.

Which Urbaniak class o ring avulsion injury is considered a relative contraindication to replantation?
III—complete degloving or complete amputation.

What type o f ap can be used i there is a so t-tissue de ect in a ype II ring avulsion injury?
Venous ow-through ap.

What is the average 2PD o a replanted thumb?
9 to 11 mm.

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What is the average 2PD o a replanted digit?
8 to 15 mm—depending on sharp versus avulsion.

What is the “No-ref ow phenomenon”?
Inability to maintain per usion to the replanted tissue despite restoration o blood ow through a technically
acceptable anastomosis. T ought to be the result o ischemia-induced endothelial injury.

What is a common long-term sequelae o digit replantation?
Cold intolerance. T is occurs more commonly in the adult population but can also af ect the pediatric population.

How much time should you tell a patient he will have to wait or cold intolerance symptoms to resolve?
At least 2 years, possibly a li etime.
LEECHES AND ANTICOAGULANTS

Scienti c name or medical leeches?
Hirudo medicinalis.

Action o hirudin?
• Binds activated thrombin (1:1).
• Inhibits conversion o brinogen to brin.
• Blocks activation o actors V, VIII, XI, vWF.
• Decreases activation o PA, protein C, plasmin.
• Prolongs thrombin-dependent coagulation tests (P , , AC , EC ).
• T ere is no direct ef ect on platelets or endothelial cells.
• Can monitor by thrombin time and P .

Excretion o hirudin?
Renal excretion.

Organism to cover while patient is on leech therapy?
Aeromonas hydrophila—enteric organism that can cause severe so t-tissue in ection. Can cover with third-
generation cephalosporin (Ce zox) or aminoglycosides (tobramycin, gentamycin) in adults. For pediatric patients,
bactrim or cipro oxacin can be sa ely used.

What is the mechanism o heparin?
Action is primarily via activation o serum antithrombin III and lowering o blood viscosity; increases A III
activity.

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What is the mechanism o dextran?
• Polysaccharide—molecular weights o 40,000 and 70,000.
• Decreases platelet aggregation by imparting a negative charge on the platelets, inactivating vWF.
• Modi ying structure o brin.
• Altering rheologic property o blood.
• Possible complications: antigenic test dose o less than 5 mL must be given prior to administration o a ull dose.
• Renal ailure—volume expansion.
• Noncardiogenic pulmonary edema.

What is the mechanism o aspirin?
• Acetylates cyclooxygenase enzyme
• Decreases arachidonic acid, thromboxane, prostacyclin
• Decreases platelet aggregation and vasoconstriction

What is the mechanism o T orazine?
Potent vasodilator.

What is the mechanism o papaverine?
Salt o an opium alkaloid. Smooth muscle relaxant especially with cerebral and peripheral ischemia associated with
arterial spasm.

What is the mechanism o Lidocaine?
Potent local vasodilatation. Commonly used as a 2% solution.

What is the de nitive role o anticoagulation in microsurgery?
Controversial. Not enough randomized controlled trials to de nitively characterize its role. Common uses:
high-dose heparin irrigation during the microanastomosis. Intravenous heparin a ter a thrombotic event with
anastomotic revision.
HYPERCOAGULABLE STATES

What percentage o venous thrombotic events in the human body are caused by genetic actors?
Inherited de ciencies account or 5% to 15% o venous thrombosis.

Is the antiphospholipid antibody associated with arterial or venous thrombosis?
It is associated with both.

What is activated protein C resistance (APC/ actor V Leiden)?
• One o the most common hereditary causes o thrombophilia.
• 4% requency in European population, extremely uncommon in A ricans, Asians, and Australians.
• APC inactivates actors V and VIII—keeps thrombosis in check.

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What is a prothrombin 2021A mutation?
• Relative risk o thrombosis with this mutation is 2.8
• Prevalence—2%
• Extremely uncommon in nonwhite population
• reatment: Coumadin 3 to 6 months; recurrence—inde nitely

What is hyperhomocysteinemia?
• Usually an enzyme de ciency in states o chronic renal disease, hypothyroid, malignancy.
• Can be associated with medications.
• Strong correlation between elevated homocysteine levels and arterial and venous disease.
• Arterial—increased cardiac, cerebral vascular disease; 3× risk.
• Venous—increased risk o thrombosis

How much does an elevated actor VIII cause a hypercoagulable state?
Levels greater than 1,500 IU/L lead to a 5× increase o thrombosis.

Does an elevated actor XI cause an increased rate o thrombosis?
Yes. Relative risk 2.2.

What is the workup or hypercoagulable states?
Be suspicious when patient has a thrombotic event early in li e (age < 45), amily history, recurrence or multiple
spontaneous abortions.
Laboratory studies to order: Antithrombin III, proteins C and S, antiphospholipid antibody, actor V Leiden,
prothrombin 2021 A mutation, homocysteinemia. Involve a hematology oncologist early.
Note: Proteins C and S and antithrombin III are decreased in acute thrombosis; antithrombin III decreased
during heparin.
SCALP REPLANTATION

What is the typical history o a scalp amputation?
Young emale actory worker with long hair, with avulsion o scalp along the supraorbital rim extending to the ears
laterally and to the nape o the neck posteriorly.

Which vessels are commonly used or replantation?
• Super cial temporal
• Posterior auricular
• Occipital
• Supraorbital
• Usually a single artery and vein can be used to replant the scalp. Vein gra ts are commonly used.

What is a common complication a ter scalp replantation?
Hematoma.

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EAR REPLANTATION

Which vessels are commonly used in ear replantation?
Super cial temporal or posterior auricular.

Venous drainage?
Veins are extremely di cult to nd and most o ten, the ear has to be leeched.

What options exist i the amputated part is not replantable?
Banking o ear cartilage or uture ear reconstruction.

What is the “pocket principle”?
T e epidermis is removed rom the severed part, leaving the cartilage covered by a thick layer o dermis. T e part is
then attached to its original position. A retroauricular incision is made and a subcutaneous pocket is created large
enough to accommodate the ear. T e ear is removed in 2 to 4 weeks.
LIP REPLANTATION

Which arteries to look or in a lip replantation?
Labial arteries.

Veins in lip replantation?
Extremely di cult, usually requires leeching.

Most common cause o lip amputation?
Dog bite.

Can the tongue be replanted?
Yes. T ree have been reported in the world literature.
LOWER EXTREMITY REPLANTATION

Although lower extremity replantation remains controversial, indications to proceed with replantation
include?
• Patient age (children do better with neurological regeneration)
• Overall condition (comorbidities and associated injuries)
• Ischemia time < 6 hours
• ype and extent o injury (guillotine, single level)
• Bilateral amputations

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What are the contraindications to lower extremity replantation?
• Poor baseline health
• Multilevel or crush injury
• Advanced age
• Severe polytrauma

What can you do with the remaining amputated leg i replantation is not possible at a below-knee
amputation site with signi cant so t-tissue loss?
Foot llet ap.
PENIS REPLANTATION

Common cause o penile amputation?
Sel -mutilation.

Vessels in penile replantation?
Dorsal vein and deep arteries in corpora.

What adjunctive therapy can be used to assist with ischemic tissues a ter replantation?
Hyperbaric oxygen therapy.
REFERENCES
Agarwal JP, rovato JM, Agarwal S, Hopkins PN, Brooks D, Buncke G. Selected outcomes o thumb replantation a ter isolated thumb
amputation injury. J Hand Surg Am. 2010;35(9):1485–1490.
Allen DM, Levin LS. Digital replantation including postoperative care. Tech Hand Up Extrem Surg. 2002;6(4):171–177.
Alpert BS, Buncke HJ Jr, Mathes SJ. Surgical treatment o the totally avulsed scalp. Clin Plast Surg. 1982;9(2):145–159.
Bieber EJ, Wood MB, Cooney WP, Amadio PC. T umb avulsion: results o replantation/revascularization. J Hand Surg Am. 1987;12(5 Pt 1):
786–790.
Buncke GM, Buncke HJ, Oliva A, Lineaweaver WC, Siko PP. Hand reconstruction with partial toe and multiple toe transplants. Clin
Plast Surg. 1992;19:859–870.
Buncke HJ Jr. Microvascular hand surgery—transplants and replants—over the past 25 Years. J Hand Surg Am. 2000;25:415–428.
Buncke HJ. Microsurgery: Transplantation, Replantation : An aAtlas Text. Philadelphia, PA: Lea & Febiger; 1991.
Buncke HJ, Chang DW. History o microsurgery. Sem Plast Surg. 2003;17(1):5–16.
Buntic RF, Buncke HJ. Success ul replantation o an amputated tongue. Plast Reconstr Surg. 1998;101:1604–1607.
de Chalain , Jones G. Replantation o the avulsed pinna: 100% survival with a single arterial anastomosis and substitution o leeches
or a venous anastomosis. Plast Reconstr Surg. 1995;95:1275–1279.
Classen DA. T e indications and reliability o vein gra t use in ree ap trans er. Can J Plast Surg. 2004 Spring;12(1):27–29.
Conrad MH, Adams WP Jr. Pharmacologic optimization in microsurgery in the new millennium. Plast Reconstr Surg. 2001;108:2088–
2096.
Converse JM. Reconstruction o the auricle. I. Plast Reconstr Surg Transplant Bull. 1958;22:150–163.
Datiashvili RO. Simultaneous replantation o both lower legs in a child: 23 years later. J Reconstr Microsurg. 2009;25(5):323–329.
Friedrich JB, Vedder NB. T umb reconstruction. Clin Plast Surg. 2011;38(4):697–712.

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Greenberg BM, May JW Jr. Great toe-to-hand trans er: role o the preoperative lateral arteriogram o oot. J Hand Surg Am. 1988;
13(3):411–414.
Goldner RD, Urbaniak JR. Replantation. In: Wol e SW, Hotchkiss RN, Pederson WC, et al., eds. Green’s Operative Hand Surgery. 6th ed.
Philadelphia, PA: Churchill Livingstone; 2011:1585–1601.
Hanel DP, Chin SH. Wrist level and proximal-upper extremity replantation. Hand Clin. 2007;23(1):13–21.
Hammond DC, Bouwense CL, Hankins W , Maxwell-Davis GS, Furdyna J, Capraro PA. Microsurgical replantation o the amputated
nose. Plast Reconstr Surg. 2000;105:2133–2136.
Hierner R, Betz AM, Comtet JJ, Berger AC. Decision making and results in subtotal and total lower leg amputations: reconstruction
versus amputation. Microsurgery. 1995;16(12):830–839.
Kay S, Werntz J, Wolf W. Ring avulsion injuries: classi cation and prognosis. J Hand Surg Am. 1989;14:204–213.
Landström J , Schuyler RW, Macris GP. Microsurgical penile replantation acilitated by postoperative HBO treatment. Microsurgery.
2004;24(1):49–55.
Mackenzie D, Sey er AE. Reconstructive surgery: lower extremity coverage. In: Mathes SJ, Hentz VR, eds. Plastic Surgery. 2nd ed.
Philadelphia, PA: WB Saunders; 2006:1369.
May JW Jr, Chait LA, O’Brien BM, Hurley JV. T e no-re ow phenomenon in experimental ree aps. Plast Reconstr Surg. 1978;61(2):
256–267.
Mladick RA. Salvage o the ear in acute trauma. Clin Plast Surg. 1978;5:427–435.
O’Brien BM. Replantation surgery. Clin Plast Surg. 1974;1(3):405–426.
Pederson WC. Replantation. Plast Reconstr Surg. 2001;107:823–841.
Sud V, Freeland AE. Skeletal xation in digital replantation. Microsurgery. 2002;22(4):165–171.
Walton RL, Beahm EK, Brown RE, et al. Microsurgical replantation o the lip: a multi-institutional experience. Plast Reconstr Surg.
1998;102:358–368.
Wei FC. Free style ree aps. Plast Reconstr Surg. 2001;114:910–916.

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415
Christopher G. Wallace, MD, MS, FRCS (Plast)
and Fu-Chan Wei, MD, FACS

What was Nicoladoni’s contribution to thumb reconstruction?
Carl Nicoladoni (1847–1902), a pioneering Austrian surgeon, was the rst to per orm the pedicled second
toe-to-hand trans er or amputated thumb reconstruction. His description was published in 1900.

On whose experimental work was the rst human microvascular great toe-to-hand trans er based?
Buncke. In 1966, Buncke et al. published their account o success ul toe-to-hand microvascular trans er in rhesus
monkeys. T is work itsel was inspired by Nicoladoni’s concept o toe-to-hand trans er rst per ormed at the end
o the 19th century.

Who per ormed the rst microvascular second toe-to-hand trans er in humans?
Yang Dongyue o Shanghai First Medical University in China per ormed the world’s rst success ul microvascular
toe-to-hand trans er, utilizing the second toe, in 1967.

When were toe transplantations rst used or reconstruction o congenital hand di erences?
In the late 1970s, when O’Brien and colleagues pioneered thumb reconstruction in children with congenital hand
di erences using microsurgical technique. T ese applications were popularized by Gilbert and others in the 1980s.

Which two arterial pedicles may supply great toe or second toe trans ers?
T e rst dorsal metatarsal artery (FDMA) and the rst plantar metatarsal artery (FPMA). T e FDMA is dominant
in 70% o cases, FPMA in 20%, and both are o equal caliber in 10% cases.

Where in the oot is the FDMA located?
T e FDMA lies between the rst and second metatarsals, at varying depths rom super cial to the interosseous
muscle to intramuscular to a position plantar to the interosseous muscle. T e FDMA passes dorsal to the deep
transverse metatarsal ligament, which connects the plantar plates o the metatarsophalangeal (M P) joints.
Toe-to-Hand Transfer
CHAPTER 44

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Is there a classi cation system to describe the various positions o the FDMA?
T ere are at least three classi cation systems but it is not necessary to learn them. By commencing the dissection
o the toe’s vascular pedicle in the web space (instead o on the dorsum o the oot), the pedicle can be revealed
retrograde and its pathway ollowed along whatever direction it takes.

Are the dorsal metatarsal and plantar metatarsal arterial systems connected?
Yes: rst, by the communicating vessels, which pass between the rst and second metatarsals; second, the two
systems converge at the rst web space.

Which digital artery o the toe is more important, the dorsal or plantar system?
T e plantar digital artery. T e dorsal digital artery is only rarely present.

What venous system should be used to drain a great toe or second toe trans er?
T e intermediate level veins, which give rise to the greater saphenous vein.

Which nerve supplies sensation to the rst web space?
T e deep peroneal nerve.

Which nerves are the most important or sensation o the trans erred toe?
T e medial and lateral proper plantar digital nerves, which are terminal branches o the medial plantar nerve. T e
digital nerves are located plantar to the plantar digital arteries.

Which tendon is cut when dissecting the FDMA on the oot dorsum?
Extensor hallucis brevis.

In which types o congenital hand conditions should a toe-to-hand trans er be considered?
Constriction band syndrome, hands with no ngers but an adequate thumb, and thumb absence with a complex
hand mal ormation. T e latter two situations o ten have absent or anomalous recipient structures. A well-thought-
out operative plan with alternative recipient vessels, nerves, and tendons must be devised. Pollicization should be
considered or isolated thumb aplasia/signi cant hypoplasia and can o er better outcomes. For all these patients a
thorough cardiorespiratory/anesthetic workup is mandatory as coexisting systems anomalies are not uncommon.

How do outcomes di er between index nger pollicization and microsurgical second toe trans er or
hypoplastic thumb reconstruction in children with radial de ciency?
an and u compared a total o 30 children reconstructed with one o these two methods. T ey reported that
patients who had undergone pollicization had earlier motor and sensory recovery and better range o motion.
Patients who received toe trans ers had higher parental satis action and per ormed better in some activities o daily
living.

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In patients who may be uture candidates or toe-to-hand trans er, which structures should be preserved
during the initial emergent treatment? Why?
Skin: oe trans ers have a paucity o skin; local aps urther injure and ultimately scar the hand, making recipient-
site preparation more dif cult; ree aps or skin coverage use all-important recipient vessels.
Joints: Intact proximal interphalangeal or metacarpophalangeal (MCP) joints will enhance mobility and unction
ollowing trans er; preservation o only the proximal articular sur ace o the MCP joint is better than saving no
articular sur ace because a composite joint reconstruction is possible.
Bone: Adequate bony length allows restoration o digital length with toe trans er, which improves appearance and
unction; the great toe should not be harvested proximal to the M P joint, necessitating a staged reconstruction
or second toe trans er i the thumb is excessively shortened.
endons: Maintaining exor tendon length ensures preservation o the exor pulley system; the complex extensor
mechanism should be saved as it is dif cult to reconstruct; less donor-site morbidity is incurred i tendons are
preserved in the hand.
Vessels: Damage to recipient vessels either precludes trans er or necessitates riskier vein gra ting.
Nerve: Preserving nerve length reduces donor-site dissection; a more distal nerve repair during trans er will speed
up sensory recovery.

How can closure o wounds in potential toe-to-hand candidates be achieved?
Pedicled distant aps (such as the pedicled groin ap) can import liberal resh uninjured tissues and do not
sacri ce local tissues or vessels.

Should arteriography o the oot be per ormed prior to surgery?
Preoperative arteriography is not required unless the donor oot has been injured or is congenitally anomalous or i
the patient has signi cant peripheral vascular disease. T e vascular pedicle is dissected in a retrograde manner, thus
it is not necessary to know its proximal course.

How does one increase pedicle length when harvesting a rst plantar metatarsal artery dominant toe?
T e rst plantar metatarsal artery is dominant in approximately 20% o patients. Its dissection is reasonably
straight orward until the deep per orator is reached, which communicates between the plantar and dorsal systems.
While it is easible to trace the pedicle retrograde between the metatarsals, it is actually sa er and more expedient
to terminate the dissection at this point and extend the pedicle with vein gra ts as necessary.

Which pedicle should be chosen when neither the rst plantar nor the rst dorsal metatarsal artery is
dominant in the web space?
When the plantar and dorsal systems are codominant (which is the case in approximately 10% o cases), one
should choose the dorsal system because it is easier to dissect and provides a lengthier pedicle.

How should one extend the incision on the plantar and the dorsal eet when harvesting a toe?
For a plantar system–dominant harvest, the incision should be extended in a straight line away rom the weight-
bearing sur aces. For a dorsal system–dominant harvest, the incision should be extended as a lazy-S incision.

What risk actors predispose to vascular compromise requiring re-exploration o single-toe transplants?
Multivariate analyses revealed that postoperative wound in ection, metacarpal hand injuries, and preceding ap
coverage were independently associated with re-exploration or vascular compromise.

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What are the most common causes o vascular compromise ound at re-exploration o single-toe transplants?
T e most common causes or vascular compromise in single-toe transplants necessitating re-exploration are:
arterial spasm (61%), arterial thrombosis (42%), and venous thrombosis (25%); more than one actor can be
ound at any one re-exploration.

What type o secondary procedures might be necessary or patients who undergo toe-to-hand trans er?
Approximately 14% o patients require surgical revisions to improve unction including: exor tendon tenolysis
(7%), arthrodesis (2%), web space deepening (2%), osteotomy or malunion (2%), or bone gra ting or nonunion.
Some patients also request aesthetic improvement.

What techniques are available to improve the cosmetic outcome o toe transplantation?
Pulp plasty improves the appearance o the toe transplant but also may be indicated i the distal pulp is too bulky
or needs improved stability. In addition, patients who have had trimmed toe or modi ed wraparound trans er
may request osteotomy o the remaining tubercle (on the side o the skeleton that was not trimmed at the primary
trans er) to remove the “swelling” on the bular side o the interphalangeal joint o the neo-digit. Recently, Ju and
Hou described a pulp transposition ap that simultaneously reduces pulp bulk whilst augmenting the waist o the
second toe at time o transplantation to smoothen the contour o the reconstructed digit. Procedures to improve
nail cosmesis are addressed in the ollowing question.

Describe a method to reduce the toenail (o the neo-thumb) to match that o the opposite normal
thumb nail.
Narrowing the toenail by excluding a portion o its tibial hal rom the trans er is probably the simplest and
most widely practiced technique o improving nail symmetry compared to the unoperated contralateral thumb.
However, this method risks nail growth and damages the specialized paronychial and eponychial contours to create
an unnaturally straight edge to the nail plate. A method to create a near-normal and symmetric nail on the
neo-thumb is perhaps the most signi cant remaining obstacle to a truly aesthetic thumb reconstruction.

How many motor units power the thumb?
Nine: our extrinsic muscles and ve intrinsic muscles.

In which important way does the motion o the great-toe MTP joint di er rom the thumb MCP joint?
T e M P range is one o hyperextension rather than exion.

What is the two-point discrimination o the great-toe in situ? Following transplantation and rehabilitation,
is the sensation in the transplanted toe better or worse than be ore trans er?
T e great toe in situ has an average static two-point discrimination o 10 mm (2× standard deviation = ± 6 mm).
Following trans er sensation varies considerably. Mean static two-point discrimination o 6.5 mm may be achieved
in patients with optimal nerve coaptation and adequate sensory reeducation.

What proportion o hand unction does the thumb represent?
40% to 50% o global hand unction.

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What types o thumb to nger pinches are commonly discussed when analyzing prehensile unction?
Pulp-to-pulp, lateral (key), and chuck three-point (tripod) pinch. In addition the thumb assists the hand in power
(cylinder) grasp. Hook grip requires only ngers. Without any digits present the hand may unction as a bat.

Any preoperative planning methods to decide the optimal position o the toe transplant or thumb
reconstruction?
Use o a prosthetic thumb by the patient can help determine the exact position o the uture transplanted toe
and or planning additional procedures, such as opponensplasties. Otherwise, care ul preoperative discussion and
analysis with the patient regarding prehension types and requirements, including at work, are important to this
decision.

What are the most common etiologies o a thumb absence/dys unction that require reconstruction?
raumatic amputation, postoncologic resection, and certain types o congenital thumb di erences.

What is the best surgical procedure to treat an acutely amputated thumb?
Replantation.

I replantation is not possible, is primary toe-to-hand trans er possible?
Yes. Advantages include decreased time in hospital and earlier return to work. T ere are no statistically signi cant
di erences in the rate o early postoperative complications between the primary and secondary trans ers.
However, subjectively, patients with primary reconstructions are less satis ed with the unction and appearance
o the reconstructed digit than patients who have lived or some time with the amputation. Primary toe-to-hand
trans er must there ore be care ully and thoroughly discussed so that the patient has a realistic expectation o
outcome; secondary reconstruction should be strongly considered i there is any doubt in the level o the patient’s
expectations.

In assessing thumb amputations through the metacarpal, injury to which structures will most negatively
inf uence the outcome o thumb reconstruction?
Injury to the thenar muscles will dramatically a ect thumb strength, stability, and mobility. When reconstructing
a metacarpal hand injury with thumb involvement, inadequate thenar unction will immediately downgrade the
unctional expectation and hence upgrade the classi cation o the metacarpal hand to IIC, no matter what the
level o thumb amputation is.

What main options are available to position the neo-thumb or opposable tripod pinch in thumb
amputations proximal to the metacarpophalangeal joint with loss o thenar musculature unction?
Pronation osteosynthesis involves xing the transplanted toe in a static opposable position at the time o toe
transplant. Dynamic opponensplasty can additionally be per ormed, primarily or at a second stage, using the
exor digitorum super cialis tendon rom the index or middle nger (or the palmaris longus tendon) and has
been shown to improve acquisition o stable tripod pinch or these proximal reconstructions.

How can circumduction be restored i the thumb basal joint is destroyed?
Basal joint mobility or improved circumduction can be achieved with an interpositional suspension arthroplasty,
usually using a strip o extensor carpi radialis longus or similar.

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What are the elements o an ideal thumb reconstruction?
T ere are three main components: (1) unctional reconstruction, requiring adequate motor power/excursion,
at least protective sensation, correct thumb length and position, stability, and absence o pain; (2) cosmetically
acceptable; (3) minimal donor-site morbidity.

What is the minimum critical length o the thumb in an otherwise normal hand?
T e interphalangeal joint level. A reconstructed thumb may be made to this length i necessary or an amputation
at this level may be tolerated.

What structure di erentiates between a proximal and a distal digital amputation?
T e insertion o the exor digitorum super cialis into the middle phalanx.

What actors determine the “correct” thumb length?
A normal thumb reaches the middle o the proximal phalanx o the index nger when the thumb is adducted. T e
correct thumb length is determined by the thenar muscle unction and the length and mobility o the remaining
ngers. I the thumb will have minimal mobility, slightly shorter length is pre erable. A shorter thumb may be
tolerated i the ngers are normal or may be required in a metacarpal hand.

What methods, other than toe-to-hand trans er, are available or thumb reconstruction?
Pollicization o an injured digit, pollicization o an uninjured digit, osteoplastic thumb reconstruction, and
distraction osteogenesis. For so t-tissue coverage o the distal tip, local and regional aps may be used. For
example, palmar advancement aps and pedicled neurovascular island aps.

Is it necessary to use the ipsilateral great toe or thumb reconstruction? Why or why not?
No. T e le t great toe is the rst choice because the right oot is generally used or driving. However, either oot
can be chosen according to the pre erence o the patient without detriment to the reconstruction.

How do the great toe and thumb di er in appearance?
T e widest diameter o the great toe is 60% greater than that o the thumb. T e great toe has a wider nail and
larger bones.

Where on the thumb should the web space attach to avoid an arachnodactylous appearance?
T e web space should meet at the MCP joint o the thumb.

When might a second toe be considered or thumb reconstruction?
A second toe may be pre erred in the ollowing circumstances: the patient re uses/cannot tolerate great toe loss;
proximal metacarpal or transcarpometacarpal joint-level injuries; when the second toe and thumb are similar in
size; in children; suboptimal reconstruction acceptable to the patient (such as on the nondominant hand).

What are the advantages o the great toe over the second toe or thumb reconstruction?
T e great toe provides a broader, stronger, more stable reconstruction. T e second toe is prone to develop a exed
posture, has a small nail and two interphalangeal joints, which leads to less stability.

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How can the f exed posture o the second toe be minimized?
By releasing the extensor digitorum longus attachment rom the M P joint, suturing the extensor digitorum
brevis to the extensor hood or interosseous tendon, tight extensor repair, pinning the interphalangeal joints in
extension or 6 weeks, and nighttime extension splinting or at least 1 year.

What are the main advantages o the second toe in thumb reconstruction?
It may be harvested with a long segment o the second metatarsal, allowing or proximal thumb injury
reconstructions. Donor-site morbidity is less than that o the great toe.

What options are available or thumb reconstruction i the great toe is too big to give an acceptable aesthetic
result?
T e great toe wraparound, the trimmed great toe or the twisted toe technique. T e second toe generally gives a
poorer aesthetic outcome.

What are the advantages o using the wraparound great toe f ap?
Preservation o great toe skeleton/tendons; aesthetic thumb reconstruction; provision o glabrous skin, nail, and
pulp with brous septa and sensibility.

What are the disadvantages o the great toe wraparound or total thumb reconstruction?
At least two secondary donor sites are required: iliac crest or thumb skeleton and a skin gra t and/or regional
ap to cover the remaining great toe. T e reconstructed thumb has no interphalangeal joint. T ere is a risk o
bone-gra t resorption and racture.

How can pulp stability be improved when per orming a wraparound toe trans er?
T e original description o the wraparound great toe trans er involved leaving the entire great toe skeleton at
the donor site. T e so t tissue o the great toe was then wrapped around an iliac crest bone gra t. Un ortunately,
patients ound that the so t tissues o the great toe swiveled around the bone gra t and this diminished prehensile
stability. By simply harvesting a portion o the distal phalanx o the toe within the trans er, however, pulp stability
could be dramatically improved as the brous septae that anchor the pulp in position are preserved.

What are the advantages o the trimmed toe trans er?
T e trimmed toe provides a more aesthetic reconstruction than a total great toe transplantation and preserves
skin or donor-site closure. It also preserves interphalangeal joint unction. T ere is, however, a reduction in
interphalangeal joint range o motion to around 18 degrees.

What structures are reduced during a trimmed great toe trans er?
For trimmed great toe trans er, the great toe skeleton and its so t tissues are reduced to match the uninjured thumb
as closely as possible. T e skin/ at is reduced according to circum erential measurements rom the uninjured
thumb taken at three levels: the eponychium, the widest girth o the interphalangeal joint, and the middle o the
proximal phalanx (the remaining skin is le t at the oot to aid wound closure). T e skeleton is trimmed axially
with an oscillating saw on the medial side o the toe. T is axial osteotomy begins at the distal phalanx, through the
joint and down the proximal phalanx, which removes approximately 4 to 6 mm o the medial joint prominence
and 2 to 4 mm o the phalangeal sha ts. It is also possible to reduce the anteroposterior dimensions o the skeleton
with burring. Critical, however, is that the lateral ( bular) side o the toe is not trimmed so that the pedicle is not
risked.