Forearm Anatomy Flashcards
what connects the radius and the ulna?
interosseous membrane
in what direction do the collagen fibers of the interosseus membrane traverse?
from radius to ulna in a lateral to medial direction
what does the orientation of the interosseus membrane help with?
transferring forces from radius to ulna when you fall
what is the distal fracture of the radius named? what is it usually from?
Colles fracture from falling
what is the displacement of the radius that occurs in a colles fracture? what is another name for this?
displaced dorsally and called the dinner form deformity
how many phalange bones are there?
14
where is the cubital fossa? what is it?
triangular depression anterior to elbow
what goes through the cubital fossa?
brachial artery and median nerve
name the fascia surrounding the forearm
antebrachial fascia
the antebrachial fascia thickens distally and forms an anterior and posterior ligament…name the anterior ligament
palmar carpal ligament
the antebrachial fascia thickens distally and forms an anterior and posterior ligament…name the posterior ligament
extensor retinaculum
distal to the palmar carpal ligament and slightly deeper is another important ligament…what is its name?
flexor retinaculum
what does the flexor retinaculum form?
the roof of the carpal tunnel
name the two forearm muscles not located posteriorly that the radial nerve innervates
brachioradialis and supinator
what is origin and insertion of the brachioradialis
brachium and radius
what is action of the brachioradialis
flexor of the arm
what is action of the supinator?
supinate the forearm
do the anterior muscles of the arm lead to pronation or supination?
pronation
do the posterior muscles of the arm lead to pronation or supination?
supination
name the five superficial anterior flexor/pronators of the forearm
pronator teres flexor carpi radialis palmaris longus flexor carpi ulnaris flexor digitorum superficialis
where do all the anterior flexor/pronators of the forearm originate?
medial epicondyle of the humerus
inflammation of the medial epicondyle is commonly called what?
golfers elbow cause using pronators and flexors of the wrist too much
what nerve innervates the pronator teres?
median nerve
what nerve innervates the flexor carpi radialis?
median nerve
what nerve innervates the palmaris longus?
median nerve
what nerve innervates the flexor carpi ulnaris?
ulnar nerve
what nerve innervates the flexor digitorum superficialis?
median nerve
name the three deep flexor/pronators of the forearm
flexor digitorum profundus
flexor pollicis longus
pronator quadratus
what is the action of the flexor pollicis longus?f
flex the thumb
what nerve innervates the flexor pollicis longus?
anterior interosseus nerve
what nerve innervates the pronator quadratus?
anterior interosseus nerve
what nerve innervates the lateral 1/2 of the flexor digitorum profundus?
anterior interosseus nerve
what never innervates the medial 1/2 of the flexor digitorum profundus?
ulnar nerve
what is the anterior interossesus nerve a branch from?
median nerve
name the two main pronators of the forearm
pronator teres
pronator quadratus
which of the pronator muscles initiates pronation and which makes it faster?
pronator quadratus initiates and teres makes it faster
what are the nerve roots of the anterior interosseus nerve that innervates the pronator quadratum?
C8 and T1
what are the nerve roots of the median nerve that innervate the pronator teres?
C6 and C7
what nerve roots of the median nerve innervate the flexor digitorum superficialis?
C78T1
the tendons of the flexor digitorum superficialis insert into what phalange joint?
proximal interphalangeal joint
the tendons of the flexor digitorum profundus insert into what phalange joint?
distal interphalangeal joint
the medial portion of the flexor digitorum profundus is innervated by the ulnar nerve…what roots are involved?
C8 and T1
the lateral portion of the flexor digitorum profunda is innervated by the anterior interosseus nerve…what roots are involved?
C8 and T1
the medial portion of the flexor digitorum profundus controls what two fingers?
4 and 5
the lateral portion of the flexor digitorum profundus controls what two fingers?
2 and 3
where do most extensors of the wrist originate? what is inflammation of this spot called?
lateral epicondyle of the humerus…tennis elbow
name the three extensors of the wrist
extensor carpi radialis longus
extensor carpi radialis brevis
extensor carpi ulnaris
the extensors of the wrist are innervated by what nerve? what are the roots?
radial…C678
name the three extensors of the digits
extensor digitorum
extensor digiti minimi
extensor indicis
the tendons of the extensors of the digits go where in the hand?
enter into the extensor expansion (hood) of the digits
explain what the extensor expansion (hood) is in the hand
long extensor tendons divide into a central band that inserts into the middle phalanx and then two lateral bands that insert into the distal phalanx…and tendon fibers from hand muscles merge with these
what does the extensor expansion help with?
fine movements of the hands
name the three extensorsabductors of the thumbs
abductor pollicis longus
extensor pollicis brevis
extensor pollicis longus
what do the boundaries of the abductor pollicis longus, extensor pollicis longus, and extensor pollicis brevis form?
boundaries of the anatomical snuff box
what two things are within the anatomical snuff box?
radial artery and scaphoid bone
name two common sites for synovial cysts in the wrist
on the extensor carpi radialis longus and brevis tendons
name the two branches of the radial nerve in the antebrachium
superficial branch and deep branch
what is the role of the superficial branch of the radial nerve in the antebrachium?
cutaneous sensory to a portion of the lateral dorsal hand
what muscle does the deep branch of the radial nerve penetrate?
supinator
after penetrating the supinator muscle, what is the deep branch of the radial nerve called?
posterior interosseus nerve
what two muscles does the ulnar nerve innervate in the forearm?
flexor carpi ulnaris and medial 1/2 of the flexor digitorum profundus
the ulnar nerve has cutaneous branches that give sensory to what portion of the arm?
medial aspect of the hand
where does the ulnar nerve pass through to get into the hand?
canal of Guyon
where does the ulnar nerve pass through to get into the antebrachium?
posterior to the medial epicondyle of the humerus in the cubital tunnel
where is the canal of guyon located in the hand?
the medial aspect of the wrist
who commonly injures the canal of guyon? why?
cyclists because of the pressure they put on that part of the wrist when riding long distance
what are the branches of the median nerve in the antebrachium
small muscular branches and the anterior interosseus nerve
name the small cutaneous nerve that branches from the median nerve
palmar branch
where does the palmar branch of the median nerve provide sensation to on the arm?
lateral aspect of the hand
which of the radial and ulnar artery has branches?
ulnar
what are the branches of the ulnar artery?
common interosseus branch that then divides into the anterior and posterior interosseus arteries
name the two main ligaments surrounding the elbow joint
radial and ulnar collateral ligaments
what ligament does the radial collateral ligament blend with?
annular ligament of the radius
what does the proximal radioulnar joint allow for?
pronation and supination of the antebrachium
what ligament surrounds the proximal radioulnar joint?
annular ligament of the radius
what is nursemaids elbow?
when radius pops out of the proximal radioulnar joint and you have dislocation of the radius
the radiocarpal joint is an articulation between what two carpal bones and what antebrachium bone?
radius of the arm and scaphoid and lunate of the carpals
metacarpophlangeal joints are stabilized by what ligaments?
collateral ligaments
name the ligament of the metacarpophalangeal joint that stabilizes between two phalanges
deep transverse metacarpal ligament branches and between two metacarpals and helps stabilize them
what is the anterior ligaments of the metacarpophalangeal joint?
palmar ligament (plate)
what is skiers/game keepers thumb?
when you rupture the ulnar collaterl ligament of the thumb
what is de quervians tenosynovitis?
inflammation of the tendons and synovial sheaths of the extensor pallicis brevis and abductor pallicis longus
what is another name for de quervians tenosynovitis?
moms/housewifes wrist
what is the test for de quervians tenosynovitis?
Finkelstein test
how do you do the finkelstein test for de quervians tenosynovitis??
thumb is flexed and wrist deviated to the ulnar side