arm muscles Flashcards
What are the muscles of the rotator cuff?
supraspinatus, subscapularis, infraspinatus, teres minor, & teres major
What places a lot of strain on the rotator cuff and commonly causes injuries?
sports that involve throwing a ball
What is the origin, insertion, and action of the supraspinatus?
O= supraspinous fossa of scapula, I= greater tubercle of humerus, A= abducts shoulder
What is the origin, insertion, and action of the subscapularis?
O= subscapular fossa of scapula, I= lesser tubercle of humerus, A= medially rotates shoulder
What is the origin, insertion, and action of the infraspinatus?
O= infraspinous fossa of scapula, I= greater tubercle of humerus, A= laterally rotates shoulder
What is the origin, insertion, and action of the teres minor?
O= lateral border of scapula, I= greater tubercle of humerus, A= laterally rotates shoulder
What is the origin, insertion, and action of the teres major?
O= inferior angle of scapula, I= intertubercle groove of humerus, A= extension, adduction, & medial rotation of the arm at shoulder joint
What are the muscles of the upper extremity?
deltoid, biceps brachii, brachialis, coracobrachialis, brachioradialis, pronator teres, & triceps brachii
What do upper arm muscles do?
cause movement at the elbow joint; they surround the humerus and insert on forearm
What is the origin, insertion, and action of the deltoid?
O= scapular spine, acromion, & clavicle, I= deltoid tuberosity of humerus, A= abducts humerus/shoulder (prime mover)
What are characteristics of the deltoid?
triangular shape; common site for injections; antagonist to latissimus dorsi
What is the origin, insertion, and action of the biceps brachii?
O= coracoid process of scapula, I= radial tuberosity, A= prime mover of flexion of forearm/elbow; supinates forearm
What is the biceps brachii?
2-headed muscle of anterior arm
What is the origin, insertion, and action of the brachialis?
O= anterior surface of distal humerus, I= ulna, A= flexes forearm
Where is the brachialis?
lies deep to biceps
What is the origin, insertion, and action of the coracobrachialis?
O= coracoid process of scapula, I= medial shaft of humerus, A= adduct & flex shoulder
What is the coracobrachialis?
antagonist to deltoid
What is the origin, insertion, and action of the brachioradialis?
O= distal humerus; superior to lateral epicondyle, I= styloid process of radius, A= synergist to brachialis in forearm flexion
What is the brachioradialis?
superficial muscle of lateral forearm
What is the origin, insertion, and action of the pronator teres?
O= medial epicondyle of humerus, I= midshaft of radius, A= pronates forearm
Where is the pronator teres?
anterior forearm superficial to brachialis
What is the origin, insertion, and action of the triceps brachii?
O= glenoid cavity/posterior humerus, I= olecranon process of ulna, A= powerful prime mover of forearm extension
What are characteristics of the triceps brachii?
antagonist of biceps; called “boxer’s muscle” because it delivers a straight arm knockout punch; 3-headed muscle of posterior arm
What are the muscles of the forearm?
flexor carpi radialis, flexor carpi ulnaris, flexor digitorum superficialis, flexor digitorum profundus, extensor carpi radialis longus, extensor carpi ulnaris, & extensor digitorum
What are characteristics of the forearm muscles?
insert on hand; have names that reflect their actions & location
What is the origin, insertion, and action of the flexor carpi radialis?
O= medial epicondyle of humerus, I= 2nd & 3rd metacarpals, A= powerful wrist flexor; abducts hand
Where is the flexor carpi radialis?
superficial; runs diagonal across forearm
What is the origin, insertion, and action of the flexor carpi ulnaris?
O= distal humerus & posterior ulna, I= 5th metacarpal & carpals, A= powerful wrist flexor; adducts hand
Where is the flexor carpi ulnaris?
superficial; medial to flexor carpi radialis
What is the origin, insertion and action of the flexor digitorum superficialis & profundus?
O= distal humerus, ulna, & radius, I= middle phalanges of 2nd-5th fingers, A= flexes wrist & middle phalanges
What is the origin, insertion and action of the extensor carpi radialis longus?
O= lateral humerus, I= 2nd & 3rd metacarpals, A= extends & abducts wrist
Where is the extensor carpi radialis longus?
superficial; runs parallel with brachioradialis
What is the origin, insertion and action of the extensor carpi ulnaris?
O= lateral epicondyle of humerus, I= 5th metacarpal, A= extends & adducts wrist
Where is the extensor carpi ulnaris?
superficial; medial & posterior forearm
What is the origin, insertion and action of the extensor digitorum?
O= lateral epicondyle of humerus, I= distal phalanges of 2nd-5th fingers, A= prime mover of finger extension; extends wrist; abducts fingers
Where is the extensor digitorum?
superficial; lies between extensor carpi radialis & extensor carpi ulnaris
