Muscles of the Head, Neck, and Back

From Chapter 11A

What is the action of the frontalis?

raises the eyebrows

What is the action of the occipitalis?

retracts the scalp

What is the action of the orbicularis oris?

compresses and purses the lips

What is the action of the orbicularis oculi?

closes the eye

What is the action of the platysma?

tenses the skin of the neck

What is the action of the zygomaticus major?

pulls the corners of the mouth superiorly

What is the action of the zygomaticus minor?

raises the upper lip and exposes the upper teeth

What is the action of the buccinator?

moves food medially between the molars

What are the origins of the sternocleidomastoid?

manubrium of the sternum, sternal end of the clavicle

What is the insertion of the sternocleidomastoid?

mastoid process of the temporal bone

What is the action of the sternocleidomastoid?

both sides flex the cervical portion of the vertebral column

What is the origin of the splenius capitis?

ligamentum nuchae

What is the insertion of the splenius capitis?

occipital bone, mastoid process of the temporal bone

What is the action of the splenius capitis?

both sides extend the head and neck

What is the origin of the splenius cervicis?

spinous processes of the thoracic vertebrae 3-6

What is the insertion of the splenius cervicis?

transverse processes of the cervical vertebrae

What is the action of the splenius cervicis?

both sides extend the head and neck

What are the muscles that form the erector spinae groups?

iliocostalis group, longissimus group, spinalis group

What is the action of the erector spinae groups?

both sides extend the vertebral column

What is the action of the quadratus lumborum?

both sides extend the lumbar portion of the vertebral column

What is the origin of the teres major?

lateral border and inferior angle of the scapula

What are the insertions of the teres major?

lesser tubercle and intertubercular sulcus of the humerus

What is the action of the teres major?

extends the arm

What are the origins of the latissimus dorsi?

spinous processes of the lower thoracic vertebrae, false ribs, iliac crest of the ilium

What is the insertion of the latissimus dorsi?

intertubercular sulcus of the humerus

What is the action of the latissimus dorsi?

extends the arm

What are the origins of the deltoid?

acromial end of the clavicle, acromion and spine of the scapula

What is the insertion of the deltoid?

deltoid tuberosity of the humerus

What is the action of the deltoid?

extends the arm

What are the origins of the pectoralis major?

clavicle, costal cartilages

What is the insertion of the pectoralis major?

intertubercular sulcus of the humerus

What is the action of the pectoralis major?

flexes the arm

What is this muscle?

frontalis

What is this muscle?

occipitalis

What is this muscle?

orbicularis oris

What is this muscle?

orbicularis oculi

What is this muscle?

platysma

What is this muscle?

zygomaticus major

What is this muscle?

zygomaticus minor

What is this muscle?

buccinator

What is this muscle?

temporalis

What are the origins of the temporalis muscle?

parietal bone, frontal bone

What is the insertion of the temporalis muscle?

coronoid process of the mandible

What is the action of the temporalis muscle?

elevates the mandible at the jaw

What is this muscle?

masseter

What is the origin of the masseter muscle?

zygomatic arch

What are the insertions of the masseter?

coronoid process, angle, and ramus of the mandible

What is the action of the masseter muscle?

elevates the mandible at the jaw

What is this muscle?

sternocleidomastoid

What is this muscle?

splenius capitis

What is this muscle?

splenius cervicis

What is this erector spinae group?

iliocostalis group

What is this erector spinae group?

longissimus group

What is this erector spinae group?

spinalis group

What is this muscle?

quadratus lumborum

What is this muscle?

teres major

What is this muscle?

latissimus dorsi

What is this muscle?

deltoid

What is this muscle?

pectoralis major