Carpal Tunnel Flashcards
what forms the carpal tunnel
carpal bones and the flexor retinaculum
what passes through the carpal tunnel
median nerve alone with 9 flexor tendons (FDS & FDP to 4 digits and FPL) with their synovial covering
what can swelling within the carpal tunnel result in
median nerve compression
nerves are highly sensitive but the flexor tendons are not
what is the most common cause
idiopathic
what conditions can predispose to carpal tunnel
rheumatoid arthritis (synovitis means less space), conditions causing fluid retention (pregnancy, diabetes, chronic renal failure, hypothyroidism due to myxoedema) fractures of the wrist
what wrist fracture more commonly contributes to carpal tunnel
colles fracture
are women or men more commonly affected
women
8:1
how does a patient present
- parathesiae in the median nerve innervated digits (thumb and radial 2.5 fingers)
- worse at night
- loss of sensation and sometimes weakness of thumb
- clumsiness of areas of the hand associated with carpal tunnel
what can be seen on examination
demonstrable loss of sensation and/or muscle wasting go the thenar eminence (more chronic severe cases)
what tests can be done to reproduce symptoms
Tinel’s test or Phalen’s test
what can confirm the diagnosis of carpal tunnel syndrome
nerve conduction studies (slowing of conduction across the wrist)
what is non operative treatment for carpal tunnel
wrist splints at night to prevent flexion or corticosteroid injections
what is surgical treatment
carpal tunnel decompression
what does carpal tunnel decompression involve
division of transverse carpal ligament under local anaesthetic
what is the risk of carpal tunnel decompression
damage to the median nerve or one of the smaller branches
