Muscles Origin Insertion Action

Erector Spinae

Origin:iliac crest

Insertion:mastoid process on skull

Action:intervertebral extension

Splenius

Origin:superior thoracic vertebrae

Insertion:occipital bone

Action:rotate head

Trapezius

Origin:posterior surface of occipital bone

Insertion:spine of scapula

Action:scapular elevation

Rhomboid major and minor

Origin:spinous processes of vertebrae T2-T5

Insertion:medial border of scapula

Action:scapular elevatoin

Levator scapulae

Origin:transverse processes of vertebrae C1-C4

Insertion:medial border of scapula near superior angle

Action:scapular elevation

Serratus anterior

Origin:external surfaces of ribs 1-8

Insertion:medial border of scapula

Action:elevates ribs

Pectoralis minor

Origin:external surfaces of ribs 3-5

Insertion:coracoid process of scapula

Action:elevates ribs

Deltoid

Origin:spine of scapula

Insertion:deltoid tuberosity of humerus

Action:arm abduction

Supraspinatus

Origin:supraspinous fossa of scapula

Insertion:greater tubercle of humerus

Action:arm abduction

Infraspinatus

Origin:infraspinous fossa of scapula

Insertion:greater tubercle of humerus

Action:arm lateral rotation

Teres minor

Origin:lateral border of scapula

Insertion:greater tubercle of humerus

Action:arm extension

Teres major

Origin:near inferior angle of scapula

Insertion:intertubercular groove

Action:arm extension

Latissimus dorsi

Origin:iliac crest

Insertion:intertubercular groove of humerus

Action:arm extension

Subscapularis

Origin:subscapular fossa of scapula

Insertion:lesser tubercle of humerus

Action:arm adduction

Pectoralis major

Origin:sternum

Insertion:intertubercular groove on humerus

Action:shoulder adduction

Biceps brachii

Origin:coracoid process of scapula

Insertion:radial tuberosity of radius

Action:arm flexion

Coracobrachialis

Origin:coracoid process of scapula

Insertion:medial surface of humerus

Action:arm flexion

Brachialis

Origin:anterior surface of humerus

Insertion:coronoid process of ulna

Action:forearm flexion

Triceps brachii

Origin:posterior surface of humerus

Insertion:olecranon process of ulna

Action:arm extension

Flexor carpi radialis

Origin:medial epicondyle of humerus

Insertion:base of metacarpal of the second digit

Action:hand flexion

Flexor carpi ulnaris

Origin:medial epicondyle of humerus

Insertion:medial carpal bones

Action:hand flexion

Pronator quadratus

Origin:anterior surface of distal ulna

Insertion:anterior surface of distal radius

Action:forearm pronation

Brachioradialis

Origin:lateral supracondylar ridge of humerus

Insertion:lateral surface of distal radius

Action:forearm flexion

Gluteus maximus

Origin:lateral surface of ilium

Insertion:gluteal tuberosity of femur

Action:thigh extension

Gluteus medius

Origin:lateral surface of ilium

Insertion:greater trochanter of femur

Action:though abduction

Iliopsoas

Origin:iliac fossa

Insertion:lesser trochanter of femur

Action:thigh flexion

Tensor fasciae latae

Origin:anterior superior iliac spine of ilium

Insertion:iliotibial tract

Action:thigh flexion

Rectus femoris

Origin:anterior inferior iliac spine of ilium

Insertion:tibial tuberosity

Action:thigh flexion

Vastus lateralis

Origin:greater trochanter of femur

Insertion:tibial tuberosity

Action:leg extension

Vastus medialis

Origin:linea aspera

Insertion:tibial tuberosity

Action:leg extension

Vastus intermedius

Origin:anterior and lateral surfaces of femoral shaft

Insertion:tibial tuberosity

Action:leg extension

Sartorius

Origin:anterior superior iliac spine of ilium

Insertion:medial surface of tibia

Action:thigh flexion

Adductor longus

Origin:body of pubis

Insertion:linea aspera of femur

Action:thigh flexion

Gracilis

Origin:body of pubis

Insertion:medial surface of tibia

Action:leg flexion

Pectineus

Origin:superior ramus of pubis

Insertion:pectineal line of femur

Action:thigh flexion

Biceps femoris

Origin:ischial tuberosity of ischium

Insertion:lateral side of head of fibula

Action:thigh extension

Semimembranosus

Origin:ischial tuberosity of ischium

Insertion:medial condyle of tibia

Action:thigh extension

Semitendinosus

Origin:ischial tuberosity of ischium

Insertion:medial surface of tibia

Action:thigh extension

Tibialis anterior

Origin: Interosseous membrane

Insertion: first metatarsal

Action:dorsiflexion

Extensor digitorum longus

Origin: interosseous membrane

Insertion: distal phalanges of digits 2-5

Action:dorsiflexion

Peroneus (fibularis) longus

Origin:head of fibula

Insertion:first metatarsal

Action:plantar flexion

Gastrocnemius

Origin:lateral condyle of femur

Insertion:calcaneus by achilles tendon

Action:leg flexion

Soleus

Origin:head of fibula

Insertion:calcaneus by achilles tendon

Action:plantar flexion

Internal intercostals

Origin:superior border of inferior rib

Insertion:inferior border of superior rib

Action:depresses ribs during expiration

Rectus abdominis

Origin:pubic symphysis

Insertion:xiphoid process

Action:forced expiration

External abdominal oblique

Origin:external surfaces of interior eight ribs

Insertion:pubic crest

Action:forced expiration

Internal abdominal oblique

Origin:iliac crest

Insertion:pubic crest

Action: trunk rotation

Transversus abdominis

Origin:iliac crest

Insertion:pubic crest

Action:compress abdomen

Orbicularis oculi

Origin:medial aspect of bony orbit

Insertion:skin around eyelids

Action:close eye

Orbicularis oris

Origin:mandible

Insertion:lips

Action:speech

Buccinator

Origin:mandible

Insertion:blends with fibers of orbicularis oris

Action:blowing

Zygomaticus major

Origin:zygomatic bone

Insertion:angle of mouth

Action:smile

Temporalis

Origin:temporal bone

Insertion:coronoid process of mandible

Action:retract mandible

Frontalis (Epicranius- frontal belly)

Origin:epicranial aponeurosis

Insertion:skin of eyebrow

Action:raise eyebrows

Masseter

Origin:zygomatic arch

Insertion:lateral surface of mandibular ramus

Action:protrude mandible

Sternohyoid

Origin:manubrium

Insertion:hyoid bone

Action:depress hyoid during swallowing

Stylohyoid

Origin:styloid process

Insertion:hyoid bone

Action:retracts hyoid

Sternocleidomastoid

Origin:manubrium

Insertion:mastoid process

Action:flex neck

Digastric

Origin:posterior belly from mastoid process

Insertion:hyoid bone

Action:elevate hyoid

Mylohyoid

Origin:inferior margin of mandible at the chin

Insertion:hyoid bone

Action:elevate hyoid during swallowing