forearm (incl elbow) Flashcards
what is antecubital fossa
trianglular depression or hollow lying infront elbow
area of transition between anatomical arm and forearm
conduit for passage of major neurovascular strcutures from arm down to forearm + hand
lateral border antecubital fossa
medial border of brachioradialis muscle
medial border antecubital fossa
lateral border of pronator teres muscle
superior border antecubital fossa
hypothetical line between epicondyles of humerus
roof of antecubital fossa
skin and fascia, reinforced by bicipital aponeurosis
floor of antecubital fossa
proximally brachialis and distally supinator muscle
what runs within roof of antecubital fossa
median cubital vein
contents of antecubitla fossa
biceps tendon
brachial artery - bifurcates at apex
median nerve
what type of joint is elbow joint
synovial hinge joint
what are the ligaments of elbow joint
ulnar collateral ligament (holds ulnar in place)
radial collateral ligament (holds head of radius in place)
where in elbow joint capsule is loose
anterior and posterior aspects to allow for movement
what type of joints are they (proximal and distal) radio-ulnar joints
pivot synovial joints - allowing supination and pronation of arm
proximal radioulnar joint
near elbow
articulation between head of radius and radial notch of ulna
distal radioulnar joint
located near wrist
articulation between ulnar notch of radius and ulnar head
what muscles cause supination at radioulnar joint
supinator
biceps brachii
what muscles cause pronation at radioulnar joint
pronator quadratus
pronator teres
what ligament supports proximal radioulnar joint by keeping head of radius in place
anular ligament
superficial compartment of muscles in anterior forearm
flexor carpi ulnaris
palmaris longus
flexor carpi radialis
pronator teres
where do all muscles in superficial compartment anterior forearm originate
common tendon which arises from medial epicondyle humerus
nerve supply and action of flexor carpi ulnaris muscle
flexion and adduction at wrist
ulnar nerve
nerve supply and action of palmaris longus muscle
flexion at wrist
median nerve
nerve supply and action of flexor carpi radialis
flexion and abduction wrist
median nerve
nerve supply and action of pronator teres
pronation of forearm (+ flex elbow)
median nerve
what muscle makes up intermediate compartment anterior forearm
flexor digitorum superficialis (FDS)
which artery and nerve pass between the 2 heads of flexor digitiorum superficlialis
median nerve and ulnar artery
attachments of FDS
2 heads: one originates from medial epicondyle humerus and the other from radius
muscle splits into 4 tendons at wrist which travel through carpal tunnel and attach to the middle phalanges of the 4 fingers
actions of FDS
flexes metacarpophalangeal joints and proximal interphalangeal joints at the 4 fingers
flexes wrist
muscles of deep compartment anterior forearm
flexor digitorum profundus
flexor pollicis longus
pronator quadratus
nerve supply and action of flexor digitorum profundus
flex distal interphalangeal joints of fingers, flexes metacarpophalangeal joints, flex wrist
medial half (acting on little and ring fingers) innervated by ulnar n and lateral half median nerve
nerve supply and action of flexor pollicis longus
flex interphalangeal joint and metacarpophalangeal joint thumb
median nerve
nerve supply and action of pronator quadratus
pronates forearm
median nerve
median nerve pathway in forearm
enters forearm medial to brachial artery. heads under pronator teres and passes down forearm between FDS and FDP
enters carpal tunnel
ulnar nerve pathway in forearm
enters forearm by passing between heads of flexor carpi ulnaris muscle
lies medial to ulnar artery at level of wrist
what artery form s deep palmar arch
radial artery
what artery forms superficial palmar arch
ulnar artery
what nerve innervates all muscles in posterior compartment forearm
radial nerve
all commonly knwn as extensor muscles
what does brachioradialis muscle do
paradoxical muscle - origin and innervation characteristic of extensor muscle but it is a flexor
flexes elbow
what muscles in posterior forearm extend and abduct/adduct hand at wrist
extensor carpi radialis longus
extensor carpi radialis brevis
extensor carpi ulnaris
what muscles in posterior forearm extend medial 4 digits
extensor digitorum
extensor indicis
extensor digiti minimi
what muscles in posterior compartment forearm extend or abduct thumb
abductor pollicis longus
extensor pollicis brevis
radial nerve in posterior forearm gives off branches…
deep branch (posterior interosseous nerve), main motor nerve of extensors
superficial branch is sensory, dorsum of hand
what is the carpal tunnel and what 2 layers is it formed from
narrow passageway found on anterior portion of wrist
serves as entrance to palm for several tendons and median nerve
2 layers: deep carpal arch and superficial flexor retinaculum
what is carpal arch
concave on palmar side, forming base and side of carpal tunnel
formed laterally by scaphoid and trapezium tubercles
formed medially by hook of the hamate and the pisiform
what is flexor retinaculum
thick connective tissue which forms roof of carpal tunnel
originates on lateral side and inserts on medial side
contents of carpal tunnel
tendon of flexor pollicis longus
4 tendons of flexor digitorum profundus
4 tendons of flexor digitorum superficialis
median nerve
intrinsic mucles of hand
thenar compartment hypothenar compartment lumbricals and long flexor tendons adductor compartment interosseous compartment
responsible for fine motor functions of hand
thenar muscels
responsible for fine movements of thumb, all innervated by median nerve
opponens pollicis
abductor pollicis brevis
flexor pollicis brevis
hypothenar muscles
all innervated by ulnar nerve
opponens digiti minimi
abductor digiti minimi
flexor digiti minimi brevis
innervation of lumbricals and what they do
they flex at MCP joint and extend at interphalangeal joints
lateral 2 (index and middle) median nerve medial 2 ulnar nerve
innervation of lumbricals and what they do
they flex at MCP joint and extend at interphalangeal joints
lateral 2 (index and middle) median nerve medial 2 ulnar nerve
interossei muscles action and innervation
DAB: dorsal interossei abduct fingers
PAD: palmar interossei adduct fingers
ulnar nerve
4 dorsal and 3 palmar
wrist joint
aka radiocarpal joint
condyloid synovial joint, marking area of transition between forearm and hanf
what is wrist joint formed by
proximal row of carpal bones (except pisiform) - scaphoid and lunate
proximally: distal end of radius and articular disk
flexion of wrist joint
contraction of muscles in anterior compartment
extension of wrist joint
contraction of muscles in posterior compartment
adduction (ulnar deviation) of wrist joint
extensor carpi ulnaris
flexor carpi ulnaris
abduction (radial deviation) wrist joint
flexor carpi radialis
abductor pollicis longus
extensor carpi radialis longus + brevis
proximal row of carpal bones
scaphoid
lunate
triquetrum
pisiform (sesamoid bone)
distal row of carpal bones
trapezium
trapezoid
capitate
hamate
anatomical snuff box ulnar (medial) border
tendon of extensor pollicis longus
anatomical snuff box radial (lateral) border
tendons of extensor pollicis brevis and abductor pollicis longus
anatomical snuff box proximal border
styloid process of radius
anatomical snuff box floor
carpal bones: scaphoid and trapezium
anatomical snuff box rood
skin
contents of anatomical snuff box
radial artery
superficial branch radial nerve
cephalic vein
articulations of elbow joint
trochlear notch of ulna with trochlea of humerus
head of radius with capitulum of humerus
arterial supply to elbow joint
cubital anastomosis which includes recurrent and collateral branches from brachial + deep brachial arteries
nerve supply to elbow joint
median, musculocutaneous and radial nerves anteriorly
ulnar nerve posteriorly
what muscle causes extention of elbow joint
triceps brachii
which muscles cause flexion of elbow joint
brachialis, biceps brachii, brachioradialis
