Anatomy Practical 2: Major Muscles, Origins, Insertions, and Actions

Rectus femoris + OIA

O: Anterior inferior iliac spine, superior margin of acetabulum

I: patella and tibial tuberosity

A: Extends leg and flexes thigh

Extensor digitorum longus + OIA

O: Lateral condyle and proximal diaphysis of the tibia

I: Medial cuneiform bones; First metatarsal

A: Extends toes dorsiflexes foot

Gastrocnemius

O: Medial and lateral condyle's of the femur

I: Posterior calcacous

A: Planter flexes foot; flexes leg

Popliteus

O: Lateral condyle of the femur

I: Posterior surface of proxilmal tibia

A: Flex leg; rotate leg

Orbicularis oculi

O: Medial Supraorbital margin of frontal bone.

I: Skin of orbital area and eyelids

A: closes eyes; pulls skin around the eye (as blinking)

Buccinator

O: molar regions of maxilla and mandible

I: orbicularis oris muscle and C.T. tissue of cheek and lips

A: pulls cheek in

Masseter

O: Zygomatic arch

I: Angle and lateral surface of ramus of Mandible

A: elevates mandible

External intercostals

O: lower edge of ribs superior to its insertion

I: upper edge of rib inferior to origin

A: Elevate ribcage

Serratus Anterior

O: First 9 ribs

I: Medial boarder of scapula

A: scapula protraction and superior rotation of scapula

Pectoralis major

O: Medial clavicle, sternum, costal cartilage 1-7

I: Greater tuberacle and lateral lip of intertubercular sulcus of humerus

A: Flexes and adducts arm; rotates arm medially

Subscapularis

O: Subs scapular fossa of scapula

I: Lesser tubercle of humerus

A: Adducts and rotates medially

Rectus abdominis

O: superior aspect of pubic bone

I: Costal cartilage of inferior ribs

A: Flex truck and compress abdominal cavity

Gluteus maximus

O: Posterior and lateral portions of ilium. sacrum, coccyx

I: Gluteal tuberosity of femur and iliotibial tract

A: extends the thigh; laterally rotates thigh; abducts thigh

Splenius capitis

O: spinous process of cervical vertebrae and C.T. of posterior of neck

I: Mastoid process and occipital bone

A: Extends the head with other muscles; rotates head to the same side as the muscle that's connecting

Levator scapulae

O: Transverse process of CI-C4

I: superior angles of scapula

A: Elevates scapula

deltoid

O: Acromion and Spine of scapula; lateral clavicle

I: Dertold tuberosity of humenus

A: Abducts arm; secondary flexes and extends arm

Triceps brachii

O: Infraglenoid tubercle (long head); posterior proximal diaphysis; most of posterior diaphysis

I: oleranon process

A: extends forearm

Brachialis

O: Distal half of the diaphysis of the anterior humerus

I: coronoid process of Ulna

A: Flexes forearm

Supinator

O: lateral epicondyle of humerus; area of the radial notch of ulna

I: Anterior/lateral area of Proximal third of radius; distal to tuberosity

A: Supinates forearm

Palmaris longus

O: Medial epicondyle of humerus

I: Flexor retinaculum and surrounding C.T. in palm of hand

A: Flexes hand; tenses dense C.T. tissue in palm

coracobrachialis

biceps brachii

Brachioradialis

anconeus

extensor carpi radialis longus

extensor capri radialis brevis

extensor digiti minimi

extensor capri ulnaris

pronator teres

Flexor carpi radialis

flexor digitorum superficialis

flexor carpi ulnaris

pronator quadratus

occipitalis

semispinalis capitis

trapezius

Rhomboid major

Rhomboid minor

Latissimus dorsi

Teres major

Teres minor

Infraspinatus

Supraspinatus

Tensor Fascia Latae

Sartorius

adductor magnus

adductor longus

adductor brevis

Pectineus

Gracillis

vastus lateralis

vastus medialis

Vastus intermediais

(under rectus femoris)

Biceps femoris

Semitendinosus

Semimembranousus

Tibialis anterior

Extensor hallucis longus

Fibularis

Gastrocnemius

Soleus

Plantaris

Tibialis posterior

Flexor digitorum longus

Flexor hallucis longus

Extensor hallucis brevis

Extensor digitorum brevis

Dorsal interosseous

abductor digiti minimi

Flexor digitorum brevis

Abductor hallucis

Iliopsoas

Gluteus medius

Gluteus minimus

Piriformis

superior gemellus

Obturator internus

Inferior gemellus

obturator externus

Quadratus femoris

Serratus posterior

sternocleidomastoid

Scalenes

Internal intercostals

pectoralis minor

External oblique

internal oblique

Transverse abdominis

Psoas major

Psoas minor

Iliacus

Omohyoid

Levator labii superioris

Zygomaticus major and minor

Risorius

Orbicularis oris

Depressor anguli oris

Depressor labii inferioris

Mentalis

Levator labii superioris alaeque nasi