The hand Flashcards
abduction and adduciton of the thumb is iin which plane
sagittal- bringing it forward and back
proximal row of carpals from lateral to medial
scaphoid, lunate, triquetrum, pisiform (sesamoid bone w/i tendon of flexor carpi)
distal row of carpals from lateral to medial
trapezium, trapezoid, capitate, hamate
mnemonic for carpals
Some (scaphoid) Lovers (lunate) Try (triquetrum) Positions (pisiform) That (trapezium) They (trapezoid) Cant (capitate) Handle (hamate)
most common carpal fracture
scaphoid
lunate most commonly dislocated
both usually from FOOSH
complications from scaphoid fractures
can disrupt blood supply causing delayed necrosis of bone
significance of 1st carpometacarpal joint
one of the most common sites of arthritis
b/w trapezium and base of first metacarpal
easy fracture in Boxer’s fracture
commonly in 5th metacarpal neck, most ROM and easily broken
which nerve tested by OK sign
anterior interosseus nerve- innervates FPL (thumb) and FDP (index finger)
palmar aponeurosis def and septa
continuation of antebrachial fascia
sends a medial septum to 5th metacarpal and lateral septum to 3rd metacarpal and divides hand into compartments
5 compartments of hand
hypothenar thenar central adductor interosseus
limit spread of infection in hand
base of palmar aponeurosis becomes…
4 longitudinal fibrous digital sheaths w/i fingers
fibrous digital sheaths contain…
superficial and deep flexor tendons and their synovial sheaths
5 annular and 4 cruciform ligaments
trigger finger patho
trauma to tendons causes scar tissue, creates nodule on tendon
causes finger to lock into flexion position as nodule catches beneath annular ligament
tenosynovitis
inflammation of synovial tendon sheaths
fn of synovial tendon sheath
permit tendons to move freely w/ less friction
hypothenar compartment muscles
3 intrinsic muscles:
abductor digiti minimi
flexor digiti minimi brevis
opponens digiti minimi
innervated by deep branch of ulnar nerve
located medially in hand
thenar compartment
located laterally
3 intrinsic muscles (mainly for opposition of thumb)
abductor pollicis brevis
flexor pollicis brevis
opponens pollicis (main one responsible for thumb opposition)
all innervated by recurrent branch of median nerve except deep head of flexor pollicis brevis
muscle of adductor compartment
adductor pollicis- fan shaped w/ two heads (transverse and oblique, contains small sesamoid bone in tendon)
innervated by deep branch of ulnar nerve
location/muscles of central compartment
under aponeurosis, contains long flexor tendons and lumbrical muscles
lumbrical muscles origin/insertion, innervation
4 intrinsic muscles arising from tendons of FDP
lateral 2 by median nerve, medial 2 by ulnar
insert into extensor expansion (hood ligament) of dorsum of digits 2-5
lumbrical function
flex digits at MCP and extend interphlangeal joints at the same time- tightens hood ligament and extends fingers
interosseus compartment location
b/w metacarpal bones
interosseus muscles
interossei muscles- aid in grip strength
3 palmar from metacarpals 2,4,5 help adduct digits toward axial line
4 dorsal interossei from metacarpals, insert into extensor expansion of digits 2,3,4- abduct digits away from axial line
all innervated by deep branch of ulnar nerve
3 extrinsimuscles providing tendons into hand
flexor pollicis longus -1
FDS- 4
FDP- 4
all passing thru carpal tunnel w/ median nerve
carpal tunnel syndrome
any condition causing reduction in size of the carpal tunnel, traps median nerve
sx in hand distal to median nerve
sx of carpal tunnel syndrome
nerve problems w/ lateral 3.5 digits along palmar surface
can lose opposiiton of thumb when thenar muscles affected
blood supply to hand all from..
ulnar and radial arteries
two terminal branches of ulnar artery
superficial palmar arch- gives common and proper palmar digital arteries
deep palmar branch
both contribute to medial aspect of hand
location of distal radial artery
courses dorsally thru anatomical snuff box, enters palm passing deep to first dorsal interosseus muscle
2 branches of radial artery
radial indicis and princeps pollicis arteries (index and thumb)
lateral aspect of hand
anastamosis of radial and ulnar arteries
deep palmar arch, radial artery w/ deep palmar branch of ulnar
superficial palmar arch- ulnar artery and superficial branch of radial
all intrinsic muslces innervated by which nerve roots
C8 and T1- via deep branch of ulnar and radial
describe sesnsory innervation to hand
ulnar- dorsal and palmar of 5th digit, half of 4th
radial- dorsal of 1,2,3, half of 4th digit
median- palmar of 1,2,3 half of 4th digit and nail beds
describe median nerves entry into hand, branches, and key innervations
enters thru carpal tunnel (except palmar branch)
gives off recurrent branch innervating thenar muscles
innervates 1st and 2nd lumbricals
common and proper digital branches for sensation, palmar carpal branch supplies central palm (prior to carpal tunnel, runs over the roof)
ulnar nerve entry into hand, branches, key innervations
over flexor retinaculum w/ ulnar artery thru canal of guyon into hand
deep branch supplies almost all intrinsic muscles (except 1 and 2 lumbrical)
superficial branch gives common and proper digital branches for sensation to digit 5 and half of 4
