Compression Neuropathies

median nerve compression syndromes

pronator syndrome, anterior interosseous nerve syndrome, carpal tunnel syndrome

ulnar nerve compression syndromes

cubital tunnel syndrome, ulnar tunnel syndrome

radial nerve compression syndrome

radial tunnel syndrome, posterior interosseous nerve syndrome

sensory innervation of hand

radial nerve on lateral/dorsal aspect, median nerve on palmar surface, ulnar nerve on lateral dorsal/palmar aspect

sensory testing

10 test - touch both hands and ask if sensation feels similar on 0-10 scale, 0 not feeling and 10 feeling the same on both sides

median nerve innervates what muscles

pronator teres, FCR, palmaris longus, FDS, via anterior interosseous n to FPL, FPD and PQ, thenar muscles APB, FPB and OP, and lumbricals of index and long fingers

ulnar nerve innervates what myscles

FCU, FDP of ring and small fingers, hypothenar muscles FDMB, ADM, ODM, lumbricals of ring and small fingers, palmar and dorsal interossei, thenar muscles of adductor pollicis and FPB

radial nerve innervates what muscles

brachioradialis, ECRL/B, via posterior interosseous nerve supinator, ECU, EDC, EIP, EDM, and thumb muscles APL, EPL, EPB

pronator teres syndrome

compression neuropathy of median nerve at elbow

5 sites of potential compression of median nerve

supracondylar process, ligament of struthers, under lacertus fibrosus, between ulnar and humeral heads of pronator teres, flexor digitorum superficialis aponeurotic arch

compression under lacertus fibrosus

attached to biceps tendon, reproduce symptoms with stretch in extension/pronation or activate with flexion/supination

between ulnar and humeral heads of pronator teres

resist pronation, stretch endrange supination to reproduce symptoms

flexor digitorum superficialis aponeurotic arch

stretch fingers into extension or resist PIP flexion of long finger or index finger

clinical presentation of pronator teres syndrome

reports forearm fatigue and pain with repetitive gripping. forceful pronation/supination, potential numbness in median nerve distribution

signs of pronator teres syndrome

decreased sensory function radial aspect of hand on palmar surface, weakness of associated muscles (compression of nerve must be severe to produce weakness of muscles)

if there is a surgery, trauma or a fracture associated with pronator teres syndrome

youre more likely to see muscle weakness signs

tinel test

lightly tapping over course of median nerve in proximal anterior forearm - positive test is reproduction of tingling, pins, needles and numbness in sensory distribution - not pain

gold standard for nerve compression

EMG/NCV testing

provocative tests for nerve compression syndromes are

specific to entrapment sites

provocative tests for pronator teres syndrome

resisted elbow flexion and supination, resisted forearm pronation with elbow extended, resisted FDS to middle finger

differential diagnosis of pronator teres syndrome

subjective report of numbess in hand is similar to carpal tunnel

difference with pronator teres syndrome and carpal tunnel

pronator teres syndrome has no nocturnal symptoms or provocation symptoms with sustained passive wrist flexion (phalen) like CTS does, CTS has negative tinel

nonsurgical interventions for pronator teres syndrome

education and relative rest to minimize provocative motions, STM/stretching, median nerve gliding, heat and NSAIDs, splint only if needed

splinting for pronator teres

elbow at 40 deg of flexion and forearm in neutral - a bit extreme of an intervention

anterior interosseous nerve syndrome

compression neuropathy of anterior interosseous nerve - 5cm distal to medial epicondyle, motor nerve only (no sensory function)

muscles innervated by AIN

FDP, FPL, PQ

causes of AIN syndrome

activities with forceful gripping, repetitive pronation, fracture, trauma, iatrogenic(surgical)

soft tissues involved with AIN syndrome

tendinous edge of deep head of pronator teres, edge of lacertus fibrosus, flexor digitorum superficialis arcade

clinical presentation of AIN

proximal forearm pain, pain with pressure on forearm, pain with resisted pronation, weakness of FPL, FDP of index and long finger and PQ

test for AIN syndrome

"ok" sign - unable to connect tips of index and thumb - would also be positive for pronator teres syndrome but without sensory deficits for AIN

interventions of AIN syndrome for overuse

education and relative rest, nerve gliding, splinting with elbow at 45-90 flexion and forearm neutral for 8 weeks

interventions of AIN syndrome for trauma

neutral wrist splint, PROM/AROM/RROM of involved joints, monitor nerve recovery

anatomy of carpal tunnel

carpal bones form floor of tunnel, transverse carpal ligament, contents are FDS, FDP and FPL tendons and median nerve

carpal tunnel syndrome

compression of median nerve within carpal tunnel - thenar muscles are usually not numb

causes of carpal tunnel syndrome

occupational activities, wrist fractures, pregnancy, RA, diabetes, obesity, wrist ratio (square wrist at higher risk), not as much with keyboarding

clinical presentation with CTS

paresthesia/pain at thumb, index, long, radial 1/2, hallmark symptoms of nocturnal paresthesia/pain relieved by shaking hand, diminished sensation along median n distribution, hand weakness, thenar m weakness

phalen test

passively sustained wrist flexion for 60 seconds - positive test is appearance of symptoms, not pain - note time before appearance of symptoms

tinel over wrist for CTS

positive test is reproduction of numbess or tingling, not pain

carpal compression test

direct manual pressure applied over carpal tunnel for 1 minute - positive test is reproduction of symptoms, not pain

gold standard for CTS diagnosis

EMG/NVC

interventions for CTS

rest from aggravating factors, splinting in 0 degrees of extension/neutral, night time most important, tendon and nerve gliding exercises

other interventions for CTS

NSAIDs, steroid injection, manual therapy to neck region suggestive of "double crush syndrome" - C5-C6, consider TOS