Know the locations, function, and innervations of the following: all rotator cuff muscles, teres major, latissimus dorsi, trapezius, levator scapulae, rhomboid major, rhomboid minor, deltoid, coracobrachialis, pectoralis major, pectoralis minor, serratus

Supraspinatus

• Abductor of the arm

• Suprascapular nerve (C4-C6)

Infraspinatus

• Lateral rotator of the arm

• Suprascapular nerve (C5-C6)

Teres minor

• Lateral rotator of the arm

• Axillary (circumflex) nerve (C5-C6)

Subscapularis

• Arm adduction and medial rotation

• Upper and lower Subscapular nerve (C5, C6, C7)

Teres major

• Arm adduction and medial rotation

• Lower subscapular nerve (C6-C7)

Latissimus Dorsi

• Adduction and medial rotation and extension of the arm

• Thoracodorsal nerve (C6, C7, C8)

Trapezius

• Accessory nerve (CN XI); cervical plexus (C3-C4)

• Entire muscles: steadies scapula on thorax

Levator scapulae

• Draws scapula medially upward while moving inferior angle medially

• Dorsal scapular nerve (C4-C5)

Rhomboid major

• Dorsal scapular nerve (C4-C5)

• Steadies scapula, draws scapula medially upward

Rhomboid minor

• Dorsal scapular nerve (C4-C5)

• Steadies scapula, draws scapula medially upward

Deltoid

• Most important abductor of the arm up to 90 degrees

• Axillary nerve (C5-C6)

Coracobrachialis

• Flexion, adduction, internal rotation

• Musculocutaneous nerve (C6, C7)

Pectoralis major

• Medial and lateral pectoral nerve (C5-T1)

• Entire muscle: adduction, internal rotation

Pectoralis minor

• Medial and lateral pectoral nerve (C6-T1)

• Draws scapula downward, causing inferior angle to move posteromedially; rotates glenoid inferiorly, assists in respiration

Serratus Anterior

• Long thoracic nerve (C5-C6-C7)

• Elevation of the arm over 90 degrees, protracts the scapula and holds it against the thoracic wall and rotates the scapula laterally to elevate the arm

Biceps brachii

• Musculocutaneous nerve (C5-C6)

• Elbow joint flexion; supination• Shoulder joint flexion; stabilization of humeral head during deltoid contraction; abduction and internal rotation of the humerus

Brachialis

• Musculocutaneous nerve (C5-C6) and radial nerve (C7, minor)

• Flexion at elbow joint

Triceps brachii

• Radial nerve (C6-C8)

• Elbow joint: extension

• Shoulder joint, long head: extension and adduction

Anconeus

• Radial nerve (C6-C8)

• Extends the elbow and tightens its joint