Appendicular Muscles-Upper Arm (BIO 201, Practical 2)

Coracobrachialis

Coracoid process of scapula

Origin of coracobrachialis

Medial aspect of humeral shaft

Insertion of coracobrachialis

Flexes arm, shoulder adduction

Action of coracobrachialis

Brachialis

Anterior surface of distal half of humerus

Origin of brachialis

Coronoid process and tuberosity of ulna

Insertion of brachialis

Prime mover of elbow flexion

Action of brachialis

Biceps Brachii

Long head: superior margin of glenoid cavity. Short head: coracoid process of scapula

Origin of biceps brachii

Tuberosity of radius, fascia of forearm

Insertion of biceps brachii

Synergist of elbow flexion

Action of biceps brachii

Triceps Brachii

Olecranon, fascia of forearm

Insertion of triceps brachii

Extends elbow

Action of triceps brachii

Biceps brachii, brachialis, brachioradialis

Flexion of elbow joint

Triceps brachii, Anconeus on forearm

Extension of elbow joint

Supraspinatus, subscapularis, teres minor, Infraspinatus

Rotator cuff muscles

Supraspinatus

Supraspinous fossa of scapula

Origin of supraspinatus

Greater tubercle of humerus

Insertion of supraspinatus

Infraspinatus

Infraspinous fossa of scapula

Origin of infraspinatus

Greater tubercle of humerus

Insertion of infraspinatus

Modulates action of deltoid, prevents humeral head from sliding upward

Action of infraspinatus

Teres Minor

Lateral border and adjacent posterior surface of scapula

Origin of Teres minor

Greater tubercle of humerus

Insertion of teres minor

Modulates action of deltoid, prevents humeral head from sliding upward

Action of teres minor

Subscapularis

Subscapular fossa of scapula

origin of subscapularis

Lesser tubercle of humerus

insertion of subscapularis

Modulates action of deltoid, prevents humeral head from sliding upward

Action of subscapularis

Deltoid

Acromion and spine of scapula, lateral portion of clavicle

Origin of deltoid

Deltoid tuberosity of humerus

insertion of deltoid

Abduct arm, medially rotate arm

Action of deltoid

Teres Major

Extends arm, medially rotates humerus

Action of Teres Major

Aids deltoid in abduction of arm, supports humeral head when carrying weight

Action of supraspinatus