Anatomy - Wrist and Hand Flashcards
what is he thumb called?
pollex
what is the pointer finger called?
index forefinger
what is the middle finger called?
digitus medius
what is the ring finger called?
ring annularis
what is the pinky finger called?
little minimus
what is the bulge of muscle called on the side of the thumb?
thenar
what is the bulge of muscle called on the side of the pinky?
little minimus
what are the proximal carpals?
scaphoid, lunate, triquetral, pisiform
what are the distal carpals?
trapezium, trapezoid, capitate , hamate
how many phalanges do we have?
14
how many bones are in the hand and wrist?
27
what is fascia?
holds tendons, BVs and nerves close to bones
what is retinacula?
in the wrist, thick deep fibrous band which holds tendons down preventing bowstrings (when flexing and extending hand)
where is the flexor retinaculum?
over anterior carpal bones, flexor tendons and median nerve pass under carpal tunnel)
where is the extensor retinaculum?
on the dorsal carpals, extensor tendons of the hand and digits pass underneath
what is the floor of the carpal tunnel?
concave arch of carpal bones
-covered by extrinsic palmar ligaments
what is the roof of the carpal tunnel?
flexor retinaculum,
attached to scaphoid and trapezium, pisiform and hamate
what is the contents of the carpal tunnel?
9 flexor tendons, vascular synovium and median nerves
-median nerve superficial to the tendons
what are the non pre-tensile movements?
not supposed to happen
pushing
hitting with flat hand ect
what are prehensile movements?
made for
grasp and grip
findamental movements of hand
dependent on positioning of fingers (digits 2-5) and thumb
what is over grip?
palm grasp
allows holding of tool or In punch
strong
long extrinsic flexors of fingers and intrinsic muscle in palm
wrist extended
what is a precision grip?
-fine control of manipulative movements
-grip between tips of fingers and thumb (opposition)
-often between thumb and index finger
-can involve other digits
-involves hold by extrinsic flexors and extensors
-precision from intrinsic muscles
what stops the ulna from articulating with the carpals?
articuclar disk
what are the movements capable between the radius and carpals?
adduct
neutral
extend
abduct
flex
what movements occur at the metacarpophalangeal joints?
-metacarpals and proximal phalanges
-flex/extend = wave bye
-abduct/adduct = move fingers apart/back
what movements occur at the interphalangeal joints?
-proximal = prox + middle
-distal = middle & distal
-flex/extend =curl and straighten digits
what joint allows thumb movement?
between the trapezium and base 1st metacarpal
what movements occur at the thumb?
-abduction
-adduction
-extension
-flexion
-opposition
-reposition
what are the intrinsic muscles of the hand?
belly inside palm
-intricate movements and precision grip
what are the extrinsic muscles of the hand?
long flexors and extensors, belly outside hand
-important in power grip
-tendons enter hand deep to retinaculi
-transverse digit in fibrous sheath
what are the most superficial flexors of the forearm?
palmaris longus
flexor digitorum superficialis
arise from medial epicondylitis of humerus
-pass anterior to elbow
-supplied by median nerve
what is the common flexor origin?
medial epicondyle of humerus
flexor digitorum superficialis?
-deepest of superficial flexors
-through carpal tunnel and inserts base of middle phalanges digits 2-5
-flexes middle phalanges of each finger
-but not the tips of the fingers
what muscle flexes the tips of fingers?
flexor digitorum profundus
what are the wrist flexor muscles
flexor carpi radialis/ulnaris
what are the deep flexor muscles of the fingers?
-flexor digitorum profundus
-flexor pollicis longus
arise from radius and ulna
flexor digitorum profundus?
proximal ant ulna and interosseous membrane
passes through carpal tunnel
inserts base of distal phalanges
flexes distal phalanges of each finger
median and ulnar nerve
what are the superficial intrinsic extensor muscles of the fingers?
extensor digitorum
-extensor digiti minimi
arise from lateral epicondyle humerus (common extensor origin)
extensor digitorum?
inserts distal and middle phalanges
extends phalanges
radial nerve
extensor indicis?
extends digit 2
arises from the posterior ulna
inserts at the exterior expansion of digit 2
innervated by deep radial nerve
what are the deep extrinsic extensor muscles of the fingers?
extensor indices
proximal to MP joint, all extensor tendons join triangular expansion and form hood over joint = extensor expansion hood
what are the extrinsic muscles of the thumb?
flexor pollicis longus
extensor pollicis longus
extensor pollicis brevis
abductor pollicis longus
flexor pollicis longus?
anterior
origin- deep; radius and interosseous membrane
inserts - base distal phalanx
same plane as flexor digitorum
extensor pollicis longus?
posterior
origin - deep; ulna and interosseous membrane
inserts - base distal phalanx
extensor pollicis longus?
posterior
origin - deep; post R and interooseois membrane
inserts - base of proximal phalanx
forms border of snuff box
abductor pollicis longus?
posterior
origin - post surface R/U and interooseous membrane
inserts - base 1st metacarpal
forms border of snuff box
what nerves supply the intrinsic muscles of the fingers?
radial and ulnar nerves
what muscles make up the hypothenar eminence?
abductor digiti minimi
flexor digiti minimi
opponens digiti minimi
attach to pisiform, hamate and flexor retinaculum
act on digit 5
innervated by ulnar nerve
what do the thenar eminence muscles do?
attach trapezium & scaphoid and lateral flexor retinaculum
insert on phalanges of thumb
innervated by median nerve
what muscles make up the thenar eminence?
abductor pollicis brevis - abducts thumb superficial
flexor pollicis brevis - draws thumb across palm, deep and med to absuctor
opponens pollicis - opposition - deepest (sits under APB)
which tendon of the finger splits?
flexor digiti superficialis
what are the lumbricles?
-4 deep muscles, median and ulnar nerve
-arise form tendons of FDP, no bony origin
-insert extensor expansions of digit 2-5
-flex digits at MP joints & extend IP joints
what are the interossei muscles
-sit in between metacarpal bones
-dep
-abduct and adduct digits
what are the palmar muscles of the interossei?
adduct, ulnar nerve
-small, arise from metacarpals 2,4 and 5
insert - phalanges 2,4 and 5
adduct fingers
what are the dorsal interossei muscles?
-abduct, ulnar nerve
-larger, arise from 2 adjacent metacarpals
-insert into ext expansions & proximal phalanges 2-4
-abduct fingers
which muscle is a powerful supinator of the forearm?
biceps brachii
where is the common flexor origin?
medial epicondyle
which carpal has a hook?
hamate
which nerve supplies sensory innervation to the medial aspect of the hand?
ulnar
Which “boat-shaped” carpal bone is palpated in the anatomical snuffbox and may be fractured in a fall onto an outstretched hand?
scaphoid
Which artery is palpable laterally at the wrist in the anatomical snuffbox?
radial
Which nerve travels through the supinator muscle?
radial
which nerve is responsible for thumb opposition?
median
Which is the correct position of brachial artery, median nerve, and median cubital vein in relation to the bicipital aponeurosis?
Only the median cubital vein is superficial to the bicipital aponeurosis, the other two are deep to it
Which nerve supplies the pronator teres muscle?
median
Which structure forms the medial border of the anatomical snuffbox in the wrist?
Tendon of extensor pollicis longus muscle
Which carpal bone is most frequently fractured?
scaphoid
The ulnar tunnel (of Guyon) transmits which structure (s)?
ulnar nerve and artery
What is innervation of lumbrical muscles in hand?
half median and half ulnar nerve
Which structure is palpable proximally in the anatomical snuffbox of hand?
Radial styloid process
