Upper Limb Compressive Neuropathies Flashcards
What structures forms the carpal tunnel of the wrist
Carpal bones & Flexor Retinaculum
What structures pass through the carpal tunnel
Median nerve
9 flexor tendons with their synovial covering
What flexor tendons pass through the carpal tunnel
Flexor Digitorum Profundus (FDP) - 4 tendons
- DEEP - tendons go all the way to the distal phalanges
Flexor Digitorum Superficilias (FDS) - 4 tendons
- SUPERFICIAL - tendons stop at middle phalanges
Flexor Pollicis Longus (FPL) - 1 tendon
- tendon inserts on palmar surface of distal 1st phalange
Causes of carpal tunnel syndrome
Idiopathic (most)
RA (synovitis = less space)
Conditions resulting in fluid retention: pregnancy diabetes chronic renal failure hypothyroidism
Consequence of #:
Colles #
Is carpal tunnel more common in men or women?
Women! (8x more likely to be affected than men)
Presentation of carpal tunnel syndrome
Paraesthesiae in the median nerve innervated digits - thumb and radial 2 and 1/2 fingers.
Loss of sensation in median nerve distribution
Weakness of thumb
+/- Wasting of thenar eminence
2 tests which are used to reproduce the symptoms of Carpal Tunnel Syndrome
Tinel’s test
Phalen’s test
What is Tinels test
percussing over the median nerve
What is Phalen’s test
holding the wrists hyper-flexed (decreases the space in the carpal tunnel)
Ix for carpal tunnel syndrome
Nerve Conduction studies - show slow conduction across the wrist
Tx for carpal tunnel syndrome
Non-operative:
wrist splints
injection of corticosteroid
Operative:
division of the transverse carpal ligament under local
What is cubital tunnel syndrome
compression of the ULNAR nerve at the elbow
Where does compression of the ulnar nerve occur
At the elbow behind the medial epicondyle (the cubital tunnel)
Presentation of cubital tunnel syndrome
Paraesthesiae in the ulnar 1 and 1/2 fingers
weakness of ulnar innervated muscles (1st dorsal interosseous and adductor pollicis)
What is Froment’s test
tests for palsy of the ulnar nerve - specifically by testing power of adductor pollicis
patient is asked to make the ‘ok’ sign with their fingers i.e. testing pinch grip. examiner then tries to pull object out the patient’s hands
