Triceps brachii:

long head

lateral head

medial head

Origin: Infraglenoid tuberosity of scapula; lateral posterior surface of humerus

Insertion: olecranon process of ulna

Action: Extends arm and forearm; Adducts arm

Biceps Brachii

Origin: long head--> supraglenoid tubercle

short head--> coracoid process

Insertion: radial tuberosity

Action: flexes arm and forearm; supinates hand

Origin: Lateral supracondylar ridge of humerus

Insertion: styloid process of radius

Action: flexes forearm

Brachialis

Origin: Anterior distal humerus

Insertion: coronoid process of ulna

Action: flexes forearm

Origin: medial epicondyle of humerus; ulna

Insertion: lateral medial shaft of radius

Action: pronates hand; flexes forearm

Origin: medial epicondyle of humerus

Insertion: second and third metacarpals

Action: flexes and abducts hand

Origin: medial epicondyle of humerus

Insertion: palmar fascia

Action: flexes hand

Origin: medial epicondyle of humerus and ulna

Insertion: pisiform, hamate, and fifth metacarpal

Action: flexes and adducts hand

Origin: medial epicondyle of humerus; ulna

Insertion: middle phalanges of digits #2 thru #5

Action: flexes proximal and middle phalanges; flexes hand

Origin: lateral supracondylar ridge of the humerus

Insertion: second metacarpal

Action: extends and abducts hand

Origin: lateral epicondyle of humerus

Insertion: third metacarpal

Action: extends and abducts hand

Origin: lateral epicondyle of humerus

Insertion: middle; distal phalanges digits 2-5

Action: extends phalanges; extends hand

Origin: lateral epicondyle of humerus

Insertion: fifth metacarpal

Action: extends and adducts hand