anatomy practical

Galea Aponeurotica

origin: occipital bone

insertion: skin around eyes

action: elevates eyebrow

innervation: facial nerve

Orbicularis Oculi

origin: maxilla and frontal bone

insertion: skin around eye

action: closes eye

innervation: facial nerve

zygomaticus major

origin: zygomatic bone

insertion: skin and muscle

action: smiling

innervation: facial nerve

zygomaticus minor

origin: zygomatic bone

insertion: skin and muscle at corner of mouth

action: smiling

innervation: facial nerve

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orbicularis oris

origin: muscles near the mouth

insertion: skin of central lip

action: closes lip; kissing

innervation: facial nerve

buccinator

origin: alveolar processes

insertion: orbicularis oris

action: compresses cheeks

innervation: facial nerve

platysma

origin: fascia in upper chest

insertion: skin and muscles below mouth; mandible

action: depresses lower lip and angle of mouth as when pouting

innervation: facial nerve

masseter

origin: zygomatic arch

insertion: lateral surface of ramus of mandible

action: elevates and protracts mandible

innervation: trigeminal nerve

temporalis

origin: temporal bone

insertion: coronoid process of anterior ramus of mandible

action: elevates and retracts mandible

innervation. trigeminal nerve

sternocleidomastoid

origin: anterior surface of sternum and upper surface of clavicle

insertion: mastoid process of temporal bone

action: laterally flexes neck on same side; together pull head forward and down; elevates sternum and first rib

innervation: accessory, C2 and C3 cervical nerves

Scalenes

origin: transverse processes of cervical vertebrae

insertion: superior and lateral surfaces of first two ribs

action: individually: laterally flexes head and neck to the same side.

together: elevate first two ribs during forceful inhalation

innervation: cervical spinal nerves

splenius capitis

origin: processes of lower cervical and upper thoracic vertebrae

insertion: occipital bone

action: individually: rotates head to opposite side.

together: extend head and neck.

Innervation: cervical and thoracic spinal nerves

quadratus lumborum

origin: iliac crest

insertion: upper lumbar vertebrae and twelfth rib

action: extends lumbar region of vertebral column

innervation: thoracic and lumbar spinal nerves

**Iliocostalis cervicis**

**Iliocostalis thoracis**

**Iliocostalis lumborum**

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Trapezius

**Origin: Occipital bone, ligamentum nuchae, and spinous processes of seventh cervical and all thoracic vertebrae**

**Insertion: Clavicle, spine, and acromion process of scapula**

**Action: Rotates and retracts scapula Superior portion elevates scapula, Inferior portion depresses scapula** 

**Innervation: Accessory nerve**