Peripheral Nerve Problems Flashcards
Seddon’s Classification - PN (3)
- neuropraxia
- axonotmesis
- neurotmesis
Neuropraxia
injury - mild
recovery
Axonotmesis
injury - severe
regeneration - 1mm/day
recovery
Neurotmesis
injury
degeneration
neuroma formation
Sunderland’s Classification PN - Degree 1
structures remain intact
local conduction block and dymyelination
Sunderland’s Classification PN - Degree 2
axonal disruption with distal (Wallerian) degeneration
Sunderland’s Classification PN - Degree 3
disruption of axons and endoneurial tubes
fascicles remain intact
Sunderland’s Classification PN - Degree 4
disruption of axons, endoneurial tubes
only epineurium intact
loss of fascicular integrity
Sunderland’s Classification PN - Degree 5
complete nerve transection
Radial Nerve Palsy
most commonly injured peripheral nerve
fx of humerus (1:10 have radial nerve complications)
elbow dislocation
Monteggia fx-dislocation
High Radial Nerve (4)
- triceps
- anconeus
- brachioradialis
- ECRL
Low Radial Nerve (9)
- ECRB
- supinator
- EDC
- EDM
- ECU
- APL
- EPL
- EPB
- EIP
High Median Nerve (7)
- PT
- FCR
- PL
- FDS
- FDP (index and long)
- FPL
- PQ
Low Median Nerve (4)
- OP
- FPB (superficial head)
- APB
- Lumbricals (index and long)
High Ulnar Nerve (2)
- FCU
2. FDP (ring and small)
Low Ulnar Nerve (8)
- ADM
- ODM
- FDM
- Lumbricals (4 and 3)
- 3 palmar interossei
- 4 dorsal interossei
- FPB (deep head)
- Add Pol
ape hand deformity
median nerve injury
claw hand deformity
ulnar nerve injury
wrist drop deformity
radial nerve injury
anterior interosseous syndrome
entrapment of motor branch of median nerve
unable to make “ok” sign
Froment’s sign
flexion of the IP with lateral pinch
FPL attempts to compensate for paralyzed or weak adductor pollicis and FPB
ulnar nerve
Wartenberg’s sign
unable to adduct the 5th finger due to weak interosseous muscle
ulnar nerve
elbow flexion test
provocative test for ulnar nerve compression
elbow flexed and wrist in neutral for up to 5 minutes
Wallerian degeneration
breakdown of the axon distal to the site of injury
occurs 48-96 hours after injury
atrophy due to PN injury
30% weight loss of tissue in first month
50-60% by two months
60-80% by four months
primary nerve repair
occurs within the first week of injury
delayed or secondary nerve repair
performed a week or more after injury
nerve graft
down when repair cannot be done with undue tension of the nerve’s cut ends
neurolysis
surgical dissection and exploration of a damaged nerve to release from restrictions or adhesions
nerve decompression
involves cutting tissue that constrict the nerve or physically moving the nerve
orthoses: high radial nerve injuries
wrist immobilizations
low profile mobilization
tenodesis mobilization
low radial nerve injury (PIN)
nerve divides in forearm into a superficial sensory branch and a motor branch (PIN) *paralysis or paresis of ulnar wrist extension, digit extension, thumb extension, and radial ABduction
*may have dorsal wrist pain
low radial nerve injury (radial tunnel syndrome)
compression in proximal forearm
- dull aching and burning in lateral forearm
- EMG result
- orthosis: long arm, elbow flexion, wrist extension, forearm supination
low radial nerve injury (superficial sensory branch)
compressions can occur with pronation from the BR and ECRL and at the distal forearm due to lack of excursion of the nerve during repetitive wrist flexion and ulnar deviation
*spontaneous recovery common
postop management: radial nerve laceration repair (above elbow/below axilla)
static orthosis elbow 90 deg flexion forearm neutral wrist extension MP 10-20 deg flexion *4 weeks: elbow to 60 deg *5 weeks: elbow to 30 deg *6 weeks: discontinue
postop management: radial nerve decompression
dynamic wrist and MP extension orthosis for function
high median nerve palsy (pronator syndrome)
compression of the nerve between the 2 heads of pronator teres muscle or under the proximal edge of the FDS arch
provocative tests for pronator syndrome
resistive elbow flexion or isolated resistive to the long finger FDS
orthoses: anterior interosseous syndrome
figure 8 splints
low median nerve palsy (carpal tunnel syndrome)
most common nerve entrapment in the UE
- paresthesia in the thumb, index, middle, and radial half of ring finger
- pregnancy induced CTS
- orthoses: wrist neutral
postop management: high median nerve injuries
orthosis blocking with the wrist in 30 deg flexion for 4-6 weeks *4 weeks: wrist to 20 deg *5 weeks: wrist to 0-10 deg *6 weeks: discontinue
postop management: median nerve laceration at wrist
usually tendon involvement at well so patient education is important
postop management: decompression of high median nerve injuries
rarely done
try conservative measures first
postop management: decompression of low median nerve injuries (CTR)
carpal tunnel release
transection of the transverse carpal ligament
many don’t need postop therapy
may do wrist orthosis for positioning
high ulnar nerve compression (cubital tunnel syndrome)
night orthosis elbow 30-70 deg forearm and wrist neutral digits free *may need anti-clawing orthosis
low ulnar nerve injuries
compression at guyon’s canal due to tumor, lipoma, or ganglion
fracture of the hook of the hamate
anti-claw orthosis
postop management: ulnar nerve laceration repair (elbow to wrist level)
dorsal blocking orthosis wrist 20-30 deg flexion MP 45 deg extension *increase wrist extension at 3 and 5 weeks *6 weeks: discontinue
postop management: high ulnar nerve decompression
cubital tunnel release
transposition: subQ or submuscular
long arm orthosis
postop management: low ulnar nerve decompression
recommend due to high incident of space occupying lesions
bulky dressings used
full ROM usually allowed
