Week 3 - Carpal Tunnel Sydrome Flashcards
what forms the carpal tunnel?
carpal bone and overlying flexor retinaculum
what passes through the carpal tunnel?
median nerve
4 flexor digitorum superficialis
4 flexor digitorum profundus
flexor pollicus longus
what is carpal tunnel syndrome?
compression of the median nerve in the carpal tunnel
what can cause carpal tunnel syndrome?
most are idiopathic
can be secondary to RA and conditions resulting fluid retention - pregnancy, diabetes, chronic renal failure, hypothyroidism
can be a consequence of fractures around the wrist (colles fracture)
who is more affected by carpal tunnel syndrome?
women more than men
how long does carpal tunnel syndrome last in pregnancy?
usually subsides after childbirth
how does carpal tunnel present?
parathesia in thumb and medial 2 1/2 fingers
worse at night
loss of sensation
weakness of the thumb or clumsiness in areas of the hand supplied by the median nerve
how can symptoms be reproduced in carpal tunnel syndrome?
Tinels test - percussing over the medial nerve
Phalens test - holding the wrists hyper-flexed (decreases space in carpal tunnel)
how does carpal tunnel syndrome appear on examination?
demonstrable loss of sensation and/or muscle wasting of the thenar eminence with chronic cases
how is carpal tunnel syndrome confirmed?
nerve conduction studies - show slowing of conduction across the wrist
what is the non-operative treatment for carpal tunnel?
wrist splints at night to prevent flexion
injection of corticosteroids
how is carpal tunnel treated surgically?
decompression via division of the transverse carpal ligament under local anaesthetic
- risk of damage to the median nerve or one of its branches
