Forearm Flashcards
body of radius has a medial facing sharpened edge indicating the attachment of the
interosseus membrane
5 muscles that originate on medial epicondyle of humerus
pronator teres flexor carpi radialis palmaris longus flexor carpi ulnaris - humeral head flexor digitorum superficialis - humeroulnar head
o of pronator teres
medial epicondyle of humerus
coronoid process of ulna
i of pronator teres
middle of lateral surface of radius
action of pronator teres
pronates forearm and flexes it
innervation of pronator teres
median n C6-C7
Which two muscles are innervated by median n. C6C7
pronator teres
flexor carpi radialis
o of flexor carpi radialis
medial epicondyle of humerus
i of flexor carpi radialis
base of 2nd metacarpal bone
action of flexor carpi radialis
flexes hand and abducts it
innervation of flexor carpi radialis
median n. C6C7
o of palmaris longus
medial epicondyle of humerus
i of palmaris longus
distal 1/2 of flexor retinaculum
palmar aponeurosis
action of palmaris longus
flexes hand
tightens palmar aponeurosis
innervation of palmaris longus
median n. C7C8
O of flexor carpi ulnaris
humeral head
ulnar head
medial epicondyle of humerus
olecranon and posterior border of ulna
i of flexor carpi ulnaris
pisiform bone
hook of hamate bone
5th metacarpal bone
action of flexor carpi ulnaris
flexes hand
adducts it
(flexion of hand requires both fcr and fcu
innervation of flexor carpi ulnaris
ulnar n. C7C8
which muscle of the anterior surface (superficial and intermediate) is not innervated by median n.
flexor carpi ulnaris
o of flexor digitorum superficialis
humeroulnar -medial epicondyle of humerus, ulnar collateral lig., and coronoid process of ulna
radial head - superior 1/2 of anterior border of radius
i of flexor digitorum superficialis
bodies of middle phalanges of medial four digits
action of flexor digitorum superficialis
flexes middle phalanges of medial 4 digits
stronger action flexes proximal phalanges and hands
innervation of flexor digitorum superficialis
median n. C7-T1
used to increase strength and speed of pronation
pronator teres
prime mover of pronation, being responsible for initiation and can act as the only pronator during slow unopposed pronation
pronator quadratus
articulates with capitulum and radial notch of ulna
radial head
o of flexor digitorum profundus
ant surface of ulna
interosseus membrane
i of flexor digitorum profundus
bases of distal phalanges of medial 4 digits
a of flexor digitorum profundus
flexes distal phalanges of medial 4 digits
innervation of flexor digitorum profundus
medial part - ulnar n. C8T1
lateral part - median n. C8T1
o of flexor pollicis longus
anterior surface of radius
interosseus membrane
i of flexor pollicis longus
base of distal phalanx of thumb
action of flexor pollicis longus
flexes phalanges of thumb
innervation of flexor pollicis longus
anterior interosseus n C8-T1 (from median n)
origin of pronator quadratus
distal 1/4 of anterior surface of ulna
i of pronator quadratus
distal 1/4 of anterior surface of radius
action of pronator quadratus
primary pronator of forearm
assist holding radius and ulna together
innervation of pronator quadratus
anterior interosseus n. C8T1 (from median n.)
which muscle is responsible for increasing speed and strength of pronation?
pronator teres
what is the primary pronator and initiator
pronator quadratus
o of brachioradialis
proximal 2/3 of lateral supraepiconylar ridge of humerus
i of brachioradialis
lateral surface of distal end of radius, proximal to styloid process
action of brachioradialis
flexes forearm
innervation of brachioradialis
radial n. C5-C7
o of extensor carpi radialis longus
lateral supracondylar ridge of humerus
i of extensor carpi radialis longus
base of 2nd metacarpal bone
action of extensor carpi radialis longus
extend and abduct hand at wrist joint
innervation of extensor carpi radialis longus
radial n. C6C7
o of extensor carpi radialis brevis
lateral epicondyle of humerus
i of extensor carpi radialis brevis
base of 3rd metacarpal bone
action of extensor carpi radialis brevis
extend and abduct hand at wrist joint
innervation of extensor carpi radialis brevis
deep branch of radial n. C7C8
o of extensor digitorum
lateral epicondyle of humerus
i of extensor digitorum
extensor expansion of medial 4 digits
action of extensor digitorum
extends medial 4 digits at MCP PIP DIP.
extends hand at wrist
innervation of extensor digitorum
posterior interosseus n C7C8 (branch of radial n)
o of extensor digiti minimi
lateral epicondyle of humerus
i of extensor digiti minimi
extensor expansion of 5th digit
action of extensor digiti minimi
extends digit 5 at MCP PIP DIP
innervation of extensor digiti minimi
posterior interosseus n C7C8
o of extensor carpi ulnaris
lateral epicondyle of humerus
posterior border of ulna
i of extensor carpi ulnaris
base of 5th metacarpal
a of extensor carpi ulnaris
extends wrist and ulnar deviation of the hand at the wrist
innervation of extensor carpi ulnaris
posterior interosseus n. C7C8
o of anconeus
lateral epicondyle of humerus
i of anconeus
lateral surface of olecranon
superior part of posterior surface of ulna
action of anconeus
assists triceps in extending elbow
stabilizes elbow
abducts ulna during pronation
innervation of anconeus
radial n C7-T1
radial deviation of hand needs what muscles
flexor carpi radialis, extensor carpi radials longus and brevis
ulnar deviation of hand needs what muscles
flexor carpi ulnaris and extensor carpi ulnaris
o of supinator
lateral epicondyle of humerus
radial collateral and annular ligaments
supinator fossa
crest of ulna
i of supinator
lateral, posterior and anterior surfaces of proximal 1/3 of radius
action of supinator
supinates forearm
innervation of supinator
deep branch of radial n. C7C8
o of abductor pollicis longus
posterior surfaces of ulna and radius and interosseus membrane
i of abductor pollicis longus
base of 1st metacarpal
action of abductor pollicis longus
abducts thumb and extends it at CMC joint
innervation of abductor pollicis longus
posterior interosseus n C7C8
o of extensor pollicis brevis
posterior surface of radius and interosseus membrane
i of extensor pollicis brevis
base of proximal phalanx of thumb via extensor expansion
a of extensor pollicis brevis
extend thumb: proximal phalanx of thumb at MCP jt
innervation of extensor pollicis brevis
posterior interosseus C7C8
o of extensor pollicis longus
posterior surface and middle of ulna and interosseus membrane
insertion of extensor pollicis longus
base of distal phalanx of thumb via extensor expansion
a of extensor pollicis longus
extends distal phalanx of thumb at IP and MCP jt
innervation of extensor pollicis longus
posterior interosseus n C7C8
o of extensor indicis
posterior surface of ulna and interosseus membrane
i of extesnsor indicis
extensor expansion of 2nd digit
a of extensor indicis
extends index finger independently
assists in wrist extension
innervation of extensor indicis
posterior interosseus n C7C8
primary mover of supination in non-forceful situation
supinator
what assists the supinator in strong, forceful movements (using a screwdriver)
biceps brachii
which of the forearm bones has a stronger articulation with the humerus
ulna
what 3 structures of ulna make the strong hinge-type jt
olecranon, coronoid process, and trochlear notch
the radius articulates with the ______ proximally, and is only anchored by the _______ _____ surrounding the head of the radius
capitulum
annular ring
what 2 bones in the hand does the radius articulate with
lunate and scaphoid
the styloid process of the _____ extends more distally than the styloid process of the _____
radius
ulna
fracture of the styloid process of the radius and displacement of it proximally
colles fracture
in a colles fracture how do you tell
styloid processes at same lvl. may also damage scaphoid bone
which two fingers may hurt or tingle when the ulnar n is hit (funny bone)
medial 2
primary n for the muscles of the anterior compartment of the forearm
median n
median n innervates all the muscles in the flexor compartment except
brachioradialis, flexor carpi ulnaris, medial part of flexor digitorum profundus
this muscle is a flexor of the forearm at the elbow, but is usually listed as occupying the posterior compartment of the forearm due to its origin near the common origin of the extensors of the forearm
brachioradialis
named muscular branch of the median n arising near the apex of the cubital fossa. courses along the anterior surface of the interosseus membrane to innervate the digit 2,3 of flexor digitorum profundus, flexor pollicis longus and pronator quadratus
anterior interosseus n
nerve posterior to medial epicondyle of humerus, deep to flexor carpi ulnaris along flexor digitorum profundus, medial to ulnar a.
ulnar n
muscular branches to flexor carpi ulnaris and flexor digitorum profundus
ulnar n
innervates medial 1/2 of palmar surface of hand (little and ring finger)
palmar cutaneous branch of ulnar n.
innervates medial 1/2 of dorsal surface of hand (little and ring finger)
dorsal cutaneous branch of ulnar n.
enters forearm on anterior side of lateral epicondyle between brachialis and brachioradialis. branches into superficial and deep branch
radial n
what is the superficial branch of the radial n.
entirely cutaneus-skin of dorsum of wrist, hand, thumb, and dorsum of digits 2,3
sweeps around lateral side of radius to extensor compartment
deep branch of radial n
innervates supinator and extensor carpi radialis brevis
deep branch of ulnar n.
innervates the muscles of the deep extensor compartment
posterior interosseus n.
travels with posterior interosseus a, a branch of the ulnar artery
posterior interosseus n. branch of radial n.
where does the brachial artery divide into the radial and ulnar branches?
cubital fossa
direct line continuation of brachial artery
radial a.
the radial a extends distally in the _____ compartment to the _____ and then swings dorsally through the _____
anterior
styloid process of radius
anatomical snuff box
the ulnar a sweeps ______ after branching from the brachial a
medially
lies on the flexor digitorum profundus, lateral to ulnar n.
ulnar a
what does ulnar a supply
medial muscles of hand and forearm, common flexor synovial sheaths and ulnar n.
ulnar a turns into ________ that divides into anterior and posterior interosseus aa.
common interosseus a
passes distally and then pierces interosseus membrane to join carpal aa
anterior interosseus a
passes through the interosseus membrane to reach the extensor compartment of forearm
posterior interosseus a.
anatomical snuff box make up
bounded by the tendons of abductor pollicis longus and extensor pollicis brevis anteriorly
the tendon of extensor pollicis longus posteriorly
the ____ a passes deep in the anatomical snuff box as it travels from the anterior compartment to the post
radial
flexor retinaclm closing over the carpal groove or sulcus
carpal tunnel
which muscle is encased in Y shaped attachment of flexor retinaculum to the scaphoid and trapezium carpal bones and does not lie in the carpal tunnel
flexor carpi radialis
space occupying lesions in the carpal tunnel will result in compression of ____ and difficult in _____
median n.
flexion