Week 12 Content Flashcards
which part of the hand is supplied mainly by the radial artery and which part is supplied mainly by the ulnar artery?
radial artery supplies the thumb and half of the 2nd finger
ulnar artery supplies the other half of the 2nd finger and fingers 3-5
what are the functions of the dorsal interosssei, palmar interossei, lumbricals, adductor pollicis, and palmaris brevis?
along with the flexors of the forearm, they work to improve the grip of the hand
name the thenar muscles, what is the function of them?
flexor pollicis brevis
abductor pollicis brevis
opponens pollicis
these muscles control the movement of the thumb towards the middle of the palm
why are the intrinsic muscles of the palm and thenar muscles so important for normal hand function?
apes and humans are the only mammals that can oppose their thumbs, which allows us to pick up small objects, pin buttons, etc.
name the hypothenar muscles. what is their function?
opponens digiti minimi
flexor digiti minimi brevis
abductor digiti minimi
they control the little finger
what does the extensor indicis allow you to do? what layer is it in?
point with your index finger; deep layer
to return form pronation to supination, what must happen?
the supinator and biceps brachii must contract to rotate the radius back to the anatomical position
name the forearm extensors from medial to lateral.
extensor carpi ulnaris extensor digiti minimi extensor digitorum extensor carpi radialis brevis extensor carpi radialis longus
the tendons of ECRB and ECRL pass under the tendons of which muscles?
abductor pollicis longus and extensor pollicis brevis
what is the name given to inflammation that occurs at the intersection of the muscle bellies of APL and EPB crossing over the ECRL and ECRB?
intersection syndrome
what is the purpose of the extensor retinaculum?
prevents bowing of the long extensor tendons
what is the purpose of the flexor retinaculum? what are its attachments?
converts the carpals into a concave surface forming the carpal tunnel. it attaches medially to the pisiform and hook of hamate and laterally to the trapezium and scaphoid
what is the purpose of the carpal tunnel?
allows passage of the flexor tendons and median nerve into the palm of the hand
describe the palmar aponeurosis.
thickening of the fascia in the palm of the hand that serves to protect the soft tissues of the palm and maintain the position of the flexor tendons
it extends from the flexor retinaculum to the heads of the metacarpals where it divides into 4 longitudinal heads adhering the fibrous tissue of the proximal phalanges
describe the synovial sheaths of all the digits and how they differ.
digits 1 and 5 have synovial sheaths that are continuous with the synovial sheaths of the palm; digits 2-4 terminate about the middle of the palm and are not continuous with the synovial sheaths of the palm
describe OINA for abductor pollicis brevis
O: scaphoid and trapezium
I: lateral side of base of proximal phalanx
N: recurrent branch of median n.
A: abducts thumb at CMC joint
describe OINA for flexor pollicis brevis.
O: flexor retinaculum and trapezium
I: lateral side of base of proximal phalanx
N: recurrent branch of median n.
A: flex thumb
describe OINA for opponens pollicis.
O: flexor retinaculum and trapezium
I: lateral side of the first metacarpal
N: recurrent branch the median n.
A: oppose thumb
describe OINA for abductor digiti minimi.
O: pisiform
I: base of proximal phalanx of 5th digit
N: ulnar n.
A: abduction of 5th digit
describe OINA for flexor digiti minimi brevis.
O: hamate
I: base of proximal phalanx of 5th digit
N: ulnar n.
A: flexes 5th digit
describe OINA for opponens digiti minimi.
O: hamate
I: medial border of 5th metacarpal
N: ulnar n.
A: oppose the 5th digit
describe OINA for adductor pollicis.
O: carpal bones and bases of metacarpals 2 and 3 (oblique head) and shaft of 4rd metacarpal (transverse head)
I: base of proximal phalanx of thumb
N: ulnar n.
A: adduct thumb
describe OINA for lumbricals.
O: tendons of FDP
I: lateral side of the extensor expansions
N: median n. (lumbricals 1 and 2) and ulnar n. (lumbricals 3 and 4)
A: flexes MP joints and extends PIP joints