10.4 Muscles of the Shoulder and Upper Limb

pectoralis minor

action: protraction/abduction of scapula, depresses scapula

attachments: ribs, coracoid process of scapula

innervation: pectoral nerves

serratus anterior

action: protraction of scapula

attachments: ribs, medial border of scapula

innervation: long thoracic nerve

trapezius

action: elevates, depresses, retracts scapula

attachments: occipital bone and spinous processes C7-T12, clavicle, acromion process and spine of scapula

innervation: accessory nerve

rhomboid minor

action: elevates and retracts scapula

attachments: spinous process of vertebrae, medial border of scapula

innervation: posterior scapular nerve

rhomboid major

action: elevate and retract scapula

attachments: spinous process of vertebrae

innervation: posterior scapular nerve

rotator cuff muscles include:

• supraspinatus

• infraspinatus

• teres minor

• subscapularis

(SITS)

supraspinatus

action: abduction of the arm

attachments: supraspinous fossa of scapula, greater tubercle of humerus

innervation: suprascapular nerve

infraspinatus

action: lateral rotation of arm

attachments: infraspinous fossa of scapula, greater tubercle of humerus

innervation: suprascapular nerve

teres minor

action: adduction of arm, lateral rotation of arm

attachments: scapula, humerus

innervation: axillary nerve

subscapularis

action: medial rotation of arm

attachments: subscapular fossa of scapula, lesser tubercle of humerus

innervation: subscapular nerves

deltoid

action: abduction of arm

attachments: acromial end of clavicle, acromion, spine of scapula, deltoid tuberosity of humerus

innervation: axillary nerve

teres major

action: extension/adduction/medial rotation of arm

attachments: scapula, humerus

innervation: lower subscapular nerve

coracobrachialis

action: flexion and adduction of arm

attachments: coracoid process of scapula, humerus

innervation: musculocutaneous nerve

pectoralis major

action: flexes/adducts/medial rotation of arm

attachments: clavicle and ribs and sternum, humerus

innervation: medial and lateral pectoral nerves

latissimus dorsi

action: extension/adduction/medial rotation of arm

attachments: vertebrae, intertubercular sulcus

innervation: thoracodorsal nerve

brachialis

action: flexion of forearm

attachments: humerus, ulna

innervation: musculocutaneous nerve; radial nerve

biceps brachii (short head and long head)

action: flexion and supination of forearm

attachments: scapula, radial tuberosity of radius

innervation: musculocutaneous nerve

triceps brachii

action: extension of forearm

attachments: long-scapula/medial and lateral-humerus, olecranon of ulna

innervation: radial nerve

brachioradialis

action: flexion of forearm

attachments: humerus, styloid process of radius

innervation: radial nerve

anconeus

action: extension of forearm

attachments: humerus, olecranon

innervation: radial nerve

pronator quadratus

action: pronates forearm

attachments: ulna, radius

innervation: median nerve

pronator teres

action: pronates forearm

attachments: ulna, radius

innervation: median nerve

supinator

action: supinates forearm

attachments: ulna, radius

innervation: radial nerve