Unit 2 Functions

latissimus dorsi

extends, adducts, and medially rotates the arm, assists in respiration

pectoralis major

adducts and medially rotates humerus, flexes and extends humerus

pectoralis minor

stabilizes scapula by drawing it inferiorly and anteriorly against thoracic wall

subclavius

anchors and depresses scapula

serratus anterior

protracts scapula and holds it against thoracic wall; superiorly rotates scapula so glenoid cavity is facing up

deltoid

anterior part

supraspinatus

initiates and assists deltoid in abduction of arm, acts with rotator cuff muscles, stabilizes humeral head glenoid cavity

infraspinatus

laterally rotates arm, may assist in adduction of arm, acts with rotator cuff muscles, stabilizes humeral head in glenoid cavity

teres minor

laterally rotates arm, weak adductor of arm, acts with rotator cuff muscles, stabilizes humeral head in glenoid cavity

teres major

adducts, extends, and medially rotates arm

subscapularis

medially rotates arm, helps hold head of humerus in glenoid cavity

biceps brachii

supinates forearm (most powerful in body) and flexes forearm when supine

coracobrachialis

helps flex and adduct arm

brachialis

flexes for

pronator teres

pronates and flexes forearm

flexor carpi radialis

flexes and abducts hand

palmaris longus

flexes hand at wrist and tenses palmar aponeurosis

flexor carpi ulnaris

flexes and adducts hand