Origins, Insertions, and Actions of Muscles

Human Anatomy Practical 2

origin of masseter

zygomatic arch

insertions of masseter

• lateral ramus

• angle of mandible

action of masseter

elevates mandible

origins of sternocleidomastoid

• manubrium

• sternal end of clavicle

insertion of sternocleidomastoid

mastoid process of temporal bone

action of sternocleidomastoid

flexes & lateral rotation of neck

origins of pectoralis major

• ribs 2-6

• body of sternum

• sternal end of clavicle

insertion of pectoralis major

bicepital groove of humerus

action of pectoralis major

flexes arm

origins of deltoid

• acromial end of clavicle

• acromion & spine of scapula

insertion of deltoid

deltoid tuberosity of humerus

action of deltoid

extends shoulder

origin of coracobrachialis

coracoid process of scapula

insertion of coracobrachialis

midshaft of humerus

action of coracobrachialis

flexes arm

origin of brachialis

anterior shaft of humerus

insertion of brachialis

coronoid process of ulna

action of brachialis

flexes elbow

origin of brachioradialis

lateral supracondylar ridge of humerus

insertion of brachioradialis

styloid process of radius

action of brachioradialis

flexes elbow

origin of extensor digitorum

lateral epicondyle of humerus

insertion of extensor digitorum

phalanges 2-5

action of extensor digitorum

extend wrist

origins of pronator teres

• medial epicondyle of humerus

• coronoid process of ulna

insertion of pronator teres

mid-lateral shaft of radius

action of pronator teres

pronates forearm

origins of gluteus maximus

• ilium

• sacrum

• coccyx

insertion of gluteus maximus

gluteal tuberosity of femur

action of gluteus maximus

extends thigh

origins of rectus femoris

• anterior inferior iliac spine

• superior margin of acetabulum

insertion of rectus femoris

tibial tuberosity

action of rectus femoris

flexes hip

origin of sartorius

anterior superior iliac spine

insertion of sartorius

tibial tuberosity

action of sartorius

flexes hip

origin of semitendinosus

ischial tuberosity

insertion of semitendinosus

medial condyle of tibia

action of semitendinosus

flexes/extends knee

origins of gastrocnemius

• lateral condyle of femur

• medial condyle of femur

insertion of gastrocnemius

calcaneus

action of gastrocnemius

extension of foot

origin of tibialis anterior

lateral tibia

insertions of tibialis anterior

• 1st metatarsal

• cuneiform bone

action of tibialis anterior

dorsiflexes foot