Wrist and Hand Flashcards
what are the three groups of bone in the wrist and hand
8 carpal bones of the wrist
5 metacarpals
phalanges (thumb 2, fingers 3)
which bones make up the proximal wrist
lateral to medial scaphoid (articulates with radius) lunate (articulates with radius) triquetrum pisiform
which bones make up the distal row of the wrist
lateral to medial trapezium trapezoid capital hamate
what are metacarpals made up of
base, shaft and head
what do the phalanges consist of
thumb - proximal and distal
finger - proximal middle and distal
what are carpometacarpal joints
between metacarpals and distal row of the carpal bones
what makes up the first caropmetacarpal joint
metacarpal 1 and trapezium
what bones of the wrist compose 2-5 carpometacarpal joints
2nd - trapezoid
3rd - capitate
4th/5th - capitate
what are metacarpophalangeal joints
condylar joints
related metacarpals and the proximal phalanges
what movements can the metacarophalanageal joints do and what are they protected by
flexion extension abduction adduction circumduction and rotation
palmar ligament and collateral ligaments
what are the four walls of the carpal tunnel
roof = flexor digitorum
medial wall = pisiform and hook of hamate
lateral = scaphoid and trapezium
what structures travel through the carpal tunnel
flexor digitorum superficlis and profundus (deep)
flexor pollicis longus
median nerve
what is the thenar eminence
three muscles in area at base of thumb
opponens pollicis, flexor pollicis brevis, abductor pollicis brevis
these muscles are innervated by the recurrent branch of the median nerve
describe the structure and role of the opponens pollicis
largest of thenar muscles deep O = tubercle of trapezium and flexor reticulum I = lateral margin of metacarpal 1 rotates and flexes meta 1 on trapezium
describe the structure and function of the abductor pollicis brevis
overlies opponens and proximal to flexor pollicis brevis
O = tubercles scaphoid and trapezium
I = lateral base of proximal phalanx + extensor hood
abducts thumb
describe the stricture and function of the flexor polliicis brevis
distal to abductor pollicis
O = tubercle of trapezium
I = lateral side, base proximal phalanx
flexes metacarpophalangeal joint of thumb
what is the hypothenar eminence
opponens digiti minimi, abductor digiti minimi flexor digiti minimi
swelling on medial side of palm
innervated by the deep branch of the ulnar nerve
describe the structure and role of the of opponens digiti minimi
deepest of three
O = hook of hamate
I = medial margin and palmar surface of metacarpal 5
describe the structure and role of the of abductor digiti minimi
overlies opponens
O = pisiform, pisohamate ligament
I = medial side base of proximal phalanx of little finger into extensor hood
principle abductor
describe the structure and role of the of flexor digiti minimi brevis
lateral to abductor minimi
O = hook of hamate
I = same as abductor
flexes at metacarpophalengeal point
apart from the thenar and hypotheanr emnincens what are the other muscles of the hand
interossei
adductor pollicis
lumbrical muscles
what are the two types of lumbricals
medial, bipennate
O = tendon of FDP, little and ring, middle and ring
I = laterally into extensor hood
innervated by deep branch of ulnar
lateral, unipennate
O = tendon of FDP middle and index
I = laterally into extensor hood
digital branches of median
they flex metacarpophalangeal but extend interphalangeal
what are the two types of interossei muscles
dorsal and palmar
describe the structure an d function of the dorsal interosseous muscles
4 bipinnate between shafts of metacarpal bones on the dorsal aspect of hand
insert into proximal phalanx
1st - largest, lateral side of index
2nd / 3rd - lateral and medial side of middle finger
4th - medial side of 5th finger
flexion and extension, major abductors of index, middle and ring at metacarpophalangeal
describe the structure and function of the palmar interosseous muscles
anterior to dorsal interosseoi
unipennate
1 isn’t always present but 2,3,4 are
medial on index finger but lateral on ring and little
adduct thumb, index, ring and little, flexion and extension due to passing through extensor hood
what is the difference between palmar and dorsal interosseous muscles
PAD - palmar adduct
DAB - dorsal abduct
what is the role of the adductor pollicis
triangular muscle
transverse (MC 3) and oblique head (base MC 2 and 3)
inserts into base of proximal phalanx of thumb and into extensor hood
adductor and opposes digits for gripping
what forms the extensor hood
tendons of the extensor digitorum and extensor pollicis longus
which tendons join into the extensor hood
extensor digiti minimi
extensor indicis, extensor pollicis brevis
what is the benefit of the extensor hood
allows intrinsic muscles of the hand to produce complex delicate movements of the digits
what are the all muscles that attach to the extensor hood
which anchor the hood
index, middle, ring, little, lumbrical, inyterossei, abductor digiti minimi
adductor pollicis and abductor pollicis brevis
what is responsible for the fine movement of the upstroke in writing
flex at MCP but extending the IPJ
intrinsic muscles working through extensor hood
what two main arteries supply the hand
radial - mainly to supply the tumblebug and the lateral side of the index finger
ulnar - medial side of index finger and reset of digits
what happens to the ulnar artery when it reaches the hand
splits into superficial player arch and deep
from superior - common palmar digital arteries
superior anastomoses with radial artery
describe the route of the radial artery in the hand
enters dorsally anastomoses with the deep palmar arch which gives rise to 5 arteries supplying the digits
where does the ulnar artery and radial artery end in the hand
ulnar terminates at the superficial arch
radial terminates at the deep arch
where do the cephalic and basilic veins originate
C - lateral side of dorsal - passes over snuffbox
B - medial side passes into dorsomedial aspect of forearm
describe the cutaneous innervation of the median nerve to the hand
C6
palmer aspect of thumb, index, middle and half of ring
dorsal aspect - distal phalanges of lateral 3.5 digits
describe the cutaneous innervation of the /radial nerve of the hand
C7
mainly dorsal apart from anterior lateral aspect of thumb, dorsal of first 3.5 digs excluding the tips
describe the cutaneous innervation of the ulnar nerve of the hand
C8
palmar - lateral 1.5 digits
dorsal lateral 1.5 digits
