Radial Nerve Entrapments

Question 1

Radial nerve motor innervation

Answer 1

Extensor muscles: BEAST
- brachioradialis
- extensors
- aconeus/abductor policis longus
- supinator
- triceps

Question 2

Radial nerve sensory innervation

Answer 2

Posterior arm
Posterior 3 1/2 digits (not finger tips - median n)

Question 3

Crutch pulsy

Answer 3

High nerve palsy (axilla)
Loss of M&S down arm

Question 4

High radial nerve injury

Answer 4

Humerus fx = damaged nerve
Motor: triceps good, but wrist drop & thumb ext weakness
Sensory: problems below injury

Question 5

Radial tunnel syndrome

Answer 5

Pain 5cm below lateral epicondyle (supinator muscle)
No sensory or motor loss
Sx aggravated by resisted supination
- don’t mistake for tennis elbow - pain with resisted extension

Question 6

Posterior interosseous nerve syndrome

Answer 6

Pure motor, deep forearm pain
Pt typically presents with dropped fingers and thumb (ext carpi radialis longus is preserved, wrist can extend & radial deviate)

Question 7

Wartenbergs syndrome aka cheiralgia paresthetica

Answer 7

Compression of superficial sensory branch
Trauma, tight watch
Pain/sensory on back of hand, NO motor loss
+tinels