muscle chart

Masseter

O: Maxilla and zygomatic arch

I: Angle and ramus of mandible

A: Elevates mandible

Buccinator

O: Maxilla and mandible

I: Orbicularis oris

A: Compress cheek

Temporalis

O: Temporal fossa

I: Coronoid process and ramus of the mandible

A: Elevates and retracts mandible

Medial Pterygoid

O: Pterygoid process, palatine bone, and maxilla

I: Ramus and angle of mandible

A: Elevates and protracts mandible; moves jaw laterally

Lateral Pterygoid

O: Greater wing of the sphenoid bone and pterygoid process

I: Mandibular condyle

A: Depresses and protracts mandible; moves jaw laterally

Zygomaticus Major

O: Zygomatic bone

I: Orbicularis oris

A: Smiling

Orbicularis Oculi

O: Bones of orbit

I: Tissue of eyelid

A: Closes eye

Orbicularis Oris

O: Fascia surrounding lips

I: Mucosa of lips

A: Closes lips

Splenius Capitis

O: Spinous process of C7 and T1–T3

I: Superior nuchal line and mastoid process

A: Extends and rotates head at neck; hyperextends neck

Erector Spinae

O: Ribs, vertebrae, sacrum, and ilium

I: Ribs, vertebrae, skull

A: Extension of vertebral column

Sternocleidomastoid

O: Sternum and clavicle

I: Mastoid process of temporal bone and superior nuchal line

A: Flexes head bilaterally; rotates head unilaterally

Serratus Anterior

O: First 8–9 ribs

I: Vertebral or medial border of scapula

A: Pulls shoulder forward; abducts and rotates it forward

Pectoralis Minor

O: Ribs 3–5

I: Coracoid process of scapula

A: Depresses shoulder; draws shoulders forward

Trapezius

O: Occipital bone, spines of C7–T12

I: Clavicle and spine of scapula

A: Elevates, adducts, and depresses scapula

Levator Scapulae

O: First 3–4 cervical vertebrae

I: Superior angle of scapula

A: Elevates scapula

Rhomboideus Major

O: Spines of T2–T5

I: Vertebral or medial border of scapula

A: Elevates and adducts scapula

Rhomboideus Minor

O: Spines of C7 and T1

I: Vertebral or medial border of scapula

A: Elevates and adducts scapula

Supraspinatus

O: Supraspinous fossa of scapula

I: Greater tubercle of humerus

A: Abducts arm; slight lateral rotation

Infraspinatus

O: Infraspinous fossa of scapula

I: Greater tubercle of humerus

A: Rotates humerus laterally; slight adduction

Teres Major

O: Inferior angle of scapula

I: Proximal end of humerus

A: Extends, adducts, and medially rotates humerus

Teres Minor

O: Axillary border of scapula

I: Proximal end of humerus

A: Adducts and laterally rotates humerus

Coracobrachialis

O: Coracoid process of scapula

I: Middle medial border of humerus

A: Flexes and adducts arm

Deltoid

O: Clavicle and spine of scapula

I: Deltoid tuberosity of humerus

A: Flexes, extends, and abducts arm

Pectoralis Major

O: Clavicle, sternum, costal cartilage, true ribs

I: Anterior aspect of proximal end of humerus

A: Flexes, adducts, and medially rotates humerus

Latissimus Dorsi

O: Spinous processes of T6–L5, iliac crest, last 3 ribs

I: Intertubercular groove of humerus

A: Extends, adducts, and medially rotates humerus

Triceps Brachii

O: Scapula near glenoid fossa and proximal humerus

I: Olecranon process of ulna

A: Extends elbow

Brachialis

O: Anterior surface of humerus

I: Coronoid process and tuberosity of ulna

A: Flexes elbow

Biceps Brachii

O: Scapula near glenoid fossa and coracoid process

I: Radial tuberosity

A: Flexes elbow; supinates forearm

Brachioradialis

O: Distal end of humerus

I: Styloid process of radius

A: Flexes elbow

Supinator

O: Lateral epicondyle of humerus

I: Proximal radius

A: Supinates forearm

Pronator Teres

O: Medial epicondyle of humerus and coronoid process of ulna

I: Lateral surface of middle of radius

A: Pronates forearm

Flexor Group

O: Humerus

I: Metacarpals

A: Flexes hand at wrist

Extensor Group

O: Humerus

I: Metacarpals

A: Extends hand at wrist

Palmaris Longus

O: Medial epicondyle of humerus

I: Palmar aponeurosis (or radial tuberosity in variation)

A: Flexes elbow; flexes wrist

External Intercostals

O: Inferior border of rib above

I: Superior border of rib below

A: Elevates ribs

Internal Intercostals

O: Superior border of rib below

I: Inferior border of rib above

A: Depresses ribs

Diaphragm

O: Xiphoid process, last 6 ribs, lumbar vertebrae

I: Central tendon

A: Increases vertical dimension of thorax

Rectus Abdominis

O: Pubic crest

I: Xiphoid process, cartilage of ribs 5–7

A: Flexes spine; compresses abdomen

External Abdominal Oblique

O: Lower 8 ribs

I: Linea alba and iliac crest

A: Flexes and rotates spine; compresses abdomen

Internal Abdominal Oblique

O: Iliac crest and lumbodorsal fascia

I: Linea alba and lower 4 ribs

A: Flexes and rotates spine; compresses abdomen

Transverse Abdominis

O: Last 6 ribs, iliac crest, lumbar fascia

I: Linea alba and pubic crest

A: Compresses abdomen

Gluteus Maximus

O: Iliac crest, sacrum, coccyx

I: Iliotibial tract of fascia latae and gluteal tuberosity

A: Extends, abducts, and rotates femur laterally

Gluteus Medius

O: Ilium

I: Greater trochanter of femur

A: Abducts and rotates femur medially

Gluteus Minimus

O: Ilium

I: Greater trochanter of femur

A: Abducts and rotates femur medially

Tensor Fascia Latae

O: Iliac crest

I: Proximal head of fibula and lateral aspect of tibia via iliotibial tract

A: Flexes and abducts femur

Adductor Longus

O: Anterior pubic bone

I: Femur

A: Flexes and adducts femur

Iliopsoas – Psoas Major

O: Transverse processes and body of lumbar vertebrae

I: Lesser trochanter of femur

A: Flexes hip joint; flexes vertebral column

Iliopsoas – Iliacus

O: Iliac crest and iliac fossa

I: Tendon of psoas major

A: Flexes hip joint

Pectineus

O: Pubic bone

I: Medial aspect of femur

A: Flexes, adducts, and rotates thigh medially

Biceps Femoris (Hamstring)

O: Ischial tuberosity and femur

I: Head of fibula and lateral condyle of tibia

A: Flexes knee; extends thigh

Semitendinosus (Hamstring)

O: Ischial tuberosity

I: Medial condyle and shaft of tibia

A: Flexes knee; extends thigh

Semimembranosus (Hamstring)

O: Ischial tuberosity

I: Medial condyle of tibia

A: Flexes knee; extends thigh

Gracilis

O: Pubic bone

I: Medial surface of tibia

A: Adducts thigh; flexes knee

Sartorius

O: Anterior superior iliac spine

I: Medial surface of tibia

A: Flexes knee; flexes and rotates thigh laterally

Rectus Femoris (Quadricep)

O: Anterior inferior iliac spine

I: Upper border of patella

A: Flexes thigh; extends knee

Vastus Lateralis (Quadricep)

O: Greater trochanter of femur

I: Patella and tibial tuberosity

A: Extends knee

Vastus Intermedius (Quadricep)

O: Anterior and lateral surface of femur

I: Patella and tibial tuberosity

A: Extends knee

Vastus Medialis (Quadricep)

O: Medial side of proximal femur

I: Patella and tibial tuberosity

A: Extends knee

Gastrocnemius

O: Medial and lateral condyles of femur

I: Calcaneus via Achilles tendon

A: Extends foot at ankle; flexes knee

Soleus

O: Head of fibula and medial border of tibia

I: Calcaneus via Achilles tendon

A: Extends foot at ankle

Peroneus (Fibularis) Longus

O: Lateral condyle of tibia, head and proximal shaft of fibula

I: Base of 1st metatarsal and 1st cuneiform

A: Everts foot; assists in extension of foot at ankle

Peroneus (Fibularis) Brevis

O: Body of fibula

I: 5th metatarsal

A: Everts foot; assists in extension of foot at ankle

Tibialis Anterior

O: Lateral condyle and body of tibia

I: 1st metatarsal and 1st cuneiform

A: Flexes foot at ankle; inverts foot

Tibialis Posterior

O: Membrane between tibia and fibula

I: 2nd, 3rd, and 4th metatarsals; navicular, cuboid, and 3rd cuneiform

A: Extends foot at ankle; inverts foot