The Hand Flashcards
where do the tendons of ED insert?
digits 2-5
what is the extensor expansion?
thin, fibrous structure that overlies the whole finger and the tip of the metacarpal bone
how many dorsal interossei are there and what is their function?
4 - abduction of the fingers - separate them out from each other - middle finger acts as an axis
why doesn’t the middle finger move?
the two central interossei insert here and cancel each other out
where are the origins and insertions of the extrinsic muscles?
origins outside hand but the insertions are inside the hand
where are the origins and insertions of the intrinsic muscles?
inside the hand - the itnrinsic muscles are the (hypo)thenar eminence, lumbrical muscles, interossei, and adductor pollicis
which nerve innervates the intrinsic muscles?
radial nerve
how many muscles in the thenar eminence?
3 - AdP, FP and OP
radial, ulnar and median nerves
what are the 3 muscles in the hypothenar eminence?
ODM, FDM, ADM - innervated by ulnar
where are the two groups of interossei muscles?
in dorsum and palm of hand - for abduction (dorsum) and adduction (palmar)
which nerve innervates the interossei?
deep branch of ulnar nerve
which nerve innervates the lumbricals?
1st and 2nd are median and 3rd and 4th are ulnar
where do lumbricals arise?
FDP tendon - runs alongside the tendon and inserts onto extensor expansion
what is motor nerve supply to the hand?
median and ulnar nerves - all muscles by ulnar except thenar and 1st and 2nd lumbricals
what happens if carpal tunnel syndrome is left untreated?
wasting of thenar eminence
