Modeling Muscles

Frontalis

Origin: galea aponeurotica

Insertion: subcutaneous tissue of eyebrows and orbicularis oculi

Function: lift eyebrows, wrinkle the forehead, draw scalp back

Sternocleidomastoid

Origin: manubrium, medial clavicle

Insertion: mastoid process

Function: neck flexion/ turns head side to side

Trapezius

Origin: superior nuchal line and external occipital protuberance

Insertion: acromion and spine of scapula, anterior 1/3 of clavicle

Function: elevate/lower scapula, adduction 

Deltoid

Origin: lateral clavicle, middle of acromion, posterior spine of scapula

Insertion: deltoid tuberosity

Function: arm abduction/ swing  arms

Biceps Brachii

Origin: coracoid process

Insertion: upper radius

Function: forearm flexion

Triceps Brachii

Origin: lateral scapula, posterior upper humerus

Insertion: olecranon process

Function: forearm extension

Rectus Abdominis

Origin: pubic symphysis and crest of pubic bone

Insertion: Xiphoid process, costal cartilages of ribs 5-7

Function: vertebral flex, compress abdomen

Sartorius

Origin: anterior superior iliac spine

Insertion: proximal tibia

Function: thigh abduction, lateral rotation

Rectus Femoris

Origin: anterior inferior iliac spine and above acetabulum

Insertion: tibial tuberosity

Function: extend leg (at knee joint)

Gastrocnemius

Origin: lateral + medial condyles and posterior femur

Insertion: calcaneus 

Function: feet flexion at plantar