muscle chart

Masseter Origin

maxilla and zygomatic arch

Masseter Insertion

angle and ramus of mandible

Masseter Action

Elevates the mandible

Buccinator Origin

maxilla and mandible

Buccinator Insertion

orbicularis oris

Buccinator Action

Compresses the cheek

Temporalis Origin

temporal fossa

Temporalis Insertion

coronoid process and ramus of the mandible

Temporalis Action

Elevates and retracts the mandible

Medial Pterygoid Origin

pterygoid process, palatine bone, and maxilla

Medial Pterygoid Insertion

ramus and angle of the mandible

Medial Pterygoid Action

Elevates and protracts the mandible, moves the jaw laterally

Lateral Pterygoid Origin

greater wing of the sphenoid bone and pterygoid process

Lateral Pterygoid Insertion

mandibular condyle

Lateral Pterygoid Action

Depresses and protracts the mandible, moves the jaw laterally

Zygomaticus Major Origin

zygomatic bone

Zygomaticus Major Insertion

orbicularis oris

Zygomaticus Major Action

Responsible for smiling

Orbicularis Oculi Origin

bones of the orbit

Orbicularis Oculi Insertion

tissue of the eyelid

Orbicularis Oculi Action

Closes the eye

Orbicularis Oris Origin

fascia surrounding the lips

Orbicularis Oris Insertion

mucosa of the lips

Orbicularis Oris Action

Closes the lips

Splenius Capitis Origin

spinous process of C7 and T1–T3

Splenius Capitis Insertion

superior nuchal line and mastoid process

Splenius Capitis Action

Extends and rotates the head at the neck, hyperextends the neck

Erector Spinae Origin

ribs, vertebrae, sacrum, and ilium

Erector Spinae Insertion

ribs, vertebrae, and the skull

Erector Spinae Action

Extends the vertebral column

Sternocleidomastoid Origin

sternum and clavicle

Sternocleidomastoid Insertion

mastoid process of the temporal bone and superior nuchal line

Sternocleidomastoid Action

Flexes the head bilaterally and rotates it unilaterally

Serratus Anterior Origin

first 8–9 ribs

Serratus Anterior Insertion

vertebral or medial border of the scapula

Serratus Anterior Action

Pulls the shoulder forward, abducts and rotates it forward

Pectoralis Minor Origin

ribs 3–5

Pectoralis Minor Insertion

coracoid process of the scapula

Pectoralis Minor Action

Depresses the shoulder and draws shoulders forward

Trapezius Origin

occipital bone and spines of C7–T12

Trapezius Insertion

clavicle and spine of the scapula

Trapezius Action

Elevates, adducts, and depresses the scapula

Levator Scapulae Origin

first 3–4 cervical vertebrae

Levator Scapulae Insertion

superior angle of the scapula

Levator Scapulae Action

Elevates the scapula

Rhomboideus Major Origin

spines of T2–T5

Rhomboideus Major Insertion

vertebral or medial border of the scapula

Rhomboideus Major Action

Elevates and adducts the scapula

Rhomboideus Minor Origin

spines of C7 and T1

Rhomboideus Minor Insertion

vertebral or medial border of the scapula

Rhomboideus Minor Action

Elevates and adducts the scapula

Supraspinatus Origin

supraspinous fossa of the scapula

Supraspinatus Insertion

greater tubercle of the humerus

Supraspinatus Action

Abducts the arm, slight lateral rotation

Infraspinatus Origin

infraspinous fossa of the scapula

Infraspinatus Insertion

greater tubercle of the humerus

Infraspinatus Action

Rotates the humerus laterally, slight adduction

Teres Major Origin

inferior angle of the scapula

Teres Major Insertion

proximal end of the humerus

Teres Major Action

Extends, adducts, and medially rotates the humerus

Teres Minor Origin

axillary border of the scapula

Teres Minor Insertion

proximal end of the humerus

Teres Minor Action

Adducts and laterally rotates the humerus

Coracobrachialis Origin

coracoid process of the scapula

Coracobrachialis Insertion

middle medial border of the humerus

Coracobrachialis Action

Flexes and adducts the arm

Deltoid Origin

clavicle and spine of the scapula

Deltoid Insertion

deltoid tuberosity of the humerus

Deltoid Action

Flexes, extends, and abducts the arm

Pectoralis Major Origin

clavicle, sternum, costal cartilage, and true ribs

Pectoralis Major Insertion

anterior aspect of the proximal end of the humerus

Pectoralis Major Action

Flexes, adducts, and medially rotates the humerus

Latissimus Dorsi Origin

spinous processes of T6–L5, iliac crest, and last 3 ribs

Latissimus Dorsi Insertion

intertubercular groove of the humerus

Latissimus Dorsi Action

Extends, adducts, and medially rotates the humerus

Triceps Brachii Origin

scapula near the glenoid fossa and proximal humerus

Triceps Brachii Insertion

olecranon process of the ulna

Triceps Brachii Action

Extends the elbow

Brachialis Origin

anterior surface of the humerus

Brachialis Insertion

coronoid process and tuberosity of ulna

Brachialis Action

Flexes the elbow

Biceps Brachii Origin

scapula near the glenoid fossa and coracoid process

Biceps Brachii Insertion

radial tuberosity

Biceps Brachii Action

Flexes the elbow and supinates the forearm

Brachioradialis Origin

distal end of the humerus

Brachioradialis Insertion

styloid process of the radius

Brachioradialis Action

Flexes the elbow

Supinator Origin

lateral epicondyle of the humerus

Supinator Insertion

proximal radius

Supinator Action

Supinates the forearm

Pronator Teres Origin

medial epicondyle of the humerus and coronoid process of ulna

Pronator Teres Insertion

lateral surface of middle radius

Pronator Teres Action

Pronates the forearm

Flexor Group Origin

humerus

Flexor Group Insertion

metacarpals

Flexor Group Action

Flexes the hand at the wrist

Extensor Group Origin

humerus

Extensor Group Insertion

metacarpals

Extensor Group Action

Extends the hand at the wrist

Palmaris Longus Origin

medial epicondyle of the humerus