Hand-Nerve Facts

Question 1

Time to replantation

Answer 1

proximal to carpus

• warm ischemia time < 6 hours
• cold ischemia time < 12 hours

distal to carpus (digit)

• warm ischemia time < 12 hours
• cold ischemia time < 24 hours

Question 2

Finger order for replant

Answer 2

thumb, long, ring, small, index

Question 3

Replant monitoring (most reliable method and pulse ox number)

Answer 3

skin temperture most reliable
- concerning changes include a > 2° drop in skin temp in less than one hour or a temperture below 30° celcius

pulse oximetry
< 94% indicates potential vascular compromise

Question 4

What is average motion after replant?

Answer 4

50% total motion

(tenolysis most common secondary surgery)

Question 5

Treatment of reperfusion injury after replant

Answer 5

allopurinol is the best adjunctive therapy agent to decrease xanthine production

mechanism thought to be related to ischemia-induced hypoxanthine conversion to xanthine

Question 6

Most common knuckle and side for sagittal band rupture (“boxers knuckle”)

Answer 6

Middle (~50%), radial (9:1)

Question 7

most important flexor pulley in thumb

Answer 7

Oblique pulley

originates at proximal half of proximal phalanx

Question 8

radial tunnel syndrome facts (4)

Answer 8

• pain only (no motor or sensory changes)
• maximal tenderness more distal than tennis elbow (4 cm distal to epicondyle)
• same sites of compression as PIN syndrom
• non-op at least 1 year

Question 9

Which of the following is considered the most common complication of an extensive medial release for resistant medial epicondylitis?

Answer 9

Medial elbow instability

Vangsness CT Jr, Jobe FW: Surgical treatment of medial epicondylitis: Results in 35 elbows. J Bone Joint Surg Br 1991;73:409-411

Question 10

To adequately expose the volar plate of the proximal interphalangeal joint of the finger, which of following
pulleys is typically incised?

Answer 10

Distal portion of C1, entire A3, and the proximal portion of C2

Question 11

intrinsic muscles innervated by the ulnar nerve

Answer 11

palmaris brevis, hypothenar
muscles, all of the interossei, adductor pollicis, and the deep head of the flexor pollicis brevis

Question 12

Which normal structures help compose the spiral cord seen in Dupuytren’s contracture?

Answer 12

pretendinous band, spiral band, lateral digital sheet, and Grayson’s ligament

NOT Cleland’s ligament

The transverse ligament of the palmar aponeurosis also not involved.

Question 13

Origin and course of the palmar cutaneous branch of the median nerve (PCBMN)

Answer 13

originates from the radial side of the nerve and travels distally with the median nerve, radial to the palmaris longus, and ulnar to the flexor carpi radialis

Question 14

extensor tendon zones of injury

Answer 14

joints are odd

Question 15

Boutonniere Deformity

Answer 15

Zone III extensor tendon injury

rupture of central slip

open or avusion treat open (

closed treat closed ext PIP splint

reconstruction vs terminal tendon tenotomy (Fowler) if fails

Question 16

Answer 16

swan neck deformity

Primary lesion is lax volar plate that allows hyperextension of PIP

Secondary lesion is imbalance of forces on the PIP joint:

• mallet injury
• FDS rupture
• intrinsic contracture (triangular = transverse retinacular ligament)
• MCP joint volar subluxation (RA)

Question 17

five compression sites described in radial tunnel syndrome

Answer 17

distal edge of the supinator; fibrous bands superficial to the radiocapitellar joint; tendinous margin of the extensor carpi radialis brevis (ECRB); radial recurrent artery (leash of Henry); and the most common site of compression, the fibrous edge of the supinator (arcade ofFrohse).

Question 18

steps releasing a PIP joint flexion contracture

Answer 18

release check rein ligaments; then accessory collateral ligament and volar plate; and finally the proper collateral ligament is then released off the proximal phalanx

Question 19

treatment

Answer 19

Treatment

• nonoperative

reduce and buddy tape to adjacent finger (3-6 weeks)
indications: dislocation is reducible

• operative

open reduction and extraction of the volar plate
indication: failed reduction or open

Question 20

treatment

Answer 20

nonoperative
splinting in extension for 6-8 weeks

allows central tendon to heal to avoid boutonneire

Question 21

structures to go through to approach this injury:

Answer 21

adequate volar exposure of the volar plate requires resection of:

proximal portion of C2 pulley
entire A3 pulley
distal C1 pulley

Question 22

indication to fix:

Answer 22

if > 40% joint involved and unstable

Question 23

Rotatory PIP dislocation treatment.

Answer 23

open reduction
indications: required in most cases

one of phalangeal condyles is buttonholed between central slip and lateral band

try closed reduction first. traction to finger with MP and PIP joints in 90 degrees of flexion.

Question 24

Answer 24

kleinert protocol

low force and low excursion rehabiliation

Question 25

Answer 25

Duran protocol

Question 26

Answer 26

synergistic motion protocols

low force and high tendon excursion

Question 27

factors affecting success of recovery following nerve repair

Answer 27

age
is single most important factor influencing success of nerve recovery
level of injury
is second most important (the more distal the injury the better the chance of recovery)
sharp transections
have better prognosis than crush injuries

Question 28

nerve fiber types

Answer 28

Question 29

nerve injury

Answer 29

Question 30

nerve cond velocity numbers

Answer 30

Question 31

limb bud development: 3 axes and signalling mechanisms

Answer 31

The proximal-distal axis is controlled by the apical
ectodermal ridge and underlying mesoderm through
fibroblast growth factors.

The radial-ulnar axis is controlled by the zone of polarizing activity through sonic hedgehog protein.

The dorsal-ventral axis is controlled by wnt-7a
protein located in the dorsal ectoderm. Transcription factor Lmx1 is induced by Wnt-7a protein and is required for dorsalization of the limb. Another transcription factor , En-1, is produced on the ventral aspect of the limb and blocks Wnt-7a expression, thereby allowing ventralization of the
limb.

Question 32

Which of the following genes is up regulated within
Dupuytren’s disease tissue as compared with the
normal fascia

Answer 32

Tenascin C (TNC)

Question 33

proximal row carpectomy indications for perilunate dislocation

Answer 33

chronic injury (defined as >8 weeks after initial injury)

Question 34

Dupuytren’s anatomy

Spiral cord:

Natatory cord:

Central cord:

Lateral cord:

Answer 34

spiral cord: lateral digital sheet, the pretendinous ligament, the spiral band, and the Grayson ligament

natatory cord: natatory ligament (palm)

Central cords: volar superficial fascia (digits)

Lateral cords: lateral digital sheets (digits)

AD with variable penetrance

Question 35

order of repair for replant

(proximal amps extra steps)

Answer 35

BE.FAN.V

First do fasciotomies, shunting (B.AVN.MS)

Question 36

temps to intervene in flap monitoring

Answer 36

< 30 deg

drops 2 deg in 1 hr

Question 37

Nerve end organs

Answer 37

(superficial)

meiSSner’s —- hairleSS skin —- remember the tip of your fingers they are hairleSS — you use them for fine touch — they are fine and quick (adaptation)

merKel’s —- folliKles(of hair) — hairy skin — for crude touch — they are crude and slow(adaptation

(deep)

Pacinian —– Pressure+ vibration —- they vibrate quickly(adaptation)

Ruffini - skin stretch

Question 38

length nerve loss to graft

Answer 38

1 inch (2.5-3cm)

less can use conduit