A+P Head and Neck Muscles

action of the epicranius

2 different actions depending on Occipitalis: when contracted holds aponeurosis in place and contraction of Frontalis will raise the eyebrows. When the Occipitalis is not contracted Aponeurosis will slide and contraction of Frontalis will furrow the eyebrows.

depressor labii inferioris

Depressor labii inferioris is a paired facial muscle located in the chin region of the face. ... The function of this muscle group is to control the position, shape and movements of the lips. The contribution of depressor labii superioris is limited to the lower lip, where it depresses the lower lip inferolaterally.

temporalis

In anatomy, the temporal muscle, also known as the temporalis, is one of the muscles of mastication. It is a broad, fan-shaped muscle on each side of the head that fills the temporal fossa, superior to the zygomatic arch so it covers much of the temporal bone. Temporal refers to the head's temples.

masseter

In human anatomy, the masseter is one of the muscles of mastication. Found only in mammals, it is particularly powerful in herbivores to facilitate chewing of plant matter. The most obvious muscle of mastication is the masseter muscle, since it is the most superficial and one of the strongest.

orbicularis oris

In human anatomy, the orbicularis oris muscle is a complex of muscles in the lips that encircles the mouth. It is a sphincter, or circular muscle, but it is actually comp

semispinalis capitis

Semispinalis capitis is a long paired muscle that belongs to the deep layer of muscles of the back. It forms the superior, and largest, component of the threepart semispinalis muscle. With semispinalis cervicis and semispinalis thoracis forming the middle and inferior divisions of the muscle, respectively.

buccinator

The buccinator muscle is the major facial muscle underlying the cheek. It holds the cheek to the teeth and assists with chewing.

depressor anguli oris

The depressor anguli oris (triangularis) is a facial muscle associated with frowning. It originates from the mandible and inserts into the angle of the mouth. The muscle is innervated by the marginal mandibular branch of the facial nerve and receives its blood supply from the facial artery

frontalis

The frontalis muscle (from Latin, meaning 'frontal muscle') is a muscle which covers parts of the forehead of the skull. Some sources consider the frontalis muscle to be a distinct muscle. However, Terminologia Anatomica currently classifies it as part of the occipitofrontalis muscle along with the occipitalis muscle

levator labii superioris

The levator labii superioris (or quadratus labii superioris) is a muscle of the human body used in facial expression. It is a broad sheet, the origin of which extends from the side of the nose to the zygomatic bone.

levator scapula

The levator scapulae is a skeletal muscle situated at the back and side of the neck. As the Latin name suggests, its main function is to lift the scapula.

mentalis

The mentalis is a paired central muscle of the lower lip, situated at the tip of the chin. It originates from the mentum and inserts into the chin soft tissue.

nasalis

The nasalis is a sphincter-like muscle of the nose whose function is to compress the nasal cartilages. It is the muscle responsible for "flaring" of the nostrils. Some people can use it to close the nostrils to prevent entry of water when underwater.

occipitalis

The occipitalis muscle (occipital belly) is a muscle which covers parts of the skull. Some sources consider the occipital muscle to be a distinct muscle. However, Terminologia Anatomica currently classifies it as part of the occipitofrontalis muscle along with the frontalis muscle.

Omohyoid

The omohyoid muscle is a muscle that depresses the hyoid. It is located in the front of the neck and consists of two bellies separated by an intermediate tendon. Its superior belly serves as the most lateral member of the infrahyoid muscles, located lateral to both the sternothyroid and thyrohyoid muscles.

orbicularis oculi

The orbicularis oculi is a muscle in the face that closes the eyelids. It arises from the nasal part of the frontal bone, from the frontal process of the maxilla in front of the lacrimal groove, and from the anterior surface and borders of a short fibrous band, the medial palpebral ligament.

platysma

The platysma is a superficial muscle that overlaps the sternocleidomastoid. It is a broad sheet arising from the fascia covering the upper parts of the pectoralis major and deltoid; its fibers cross the clavicle, and proceed obliquely upward and medially along the side of the neck

risorius

The risorius is a muscle of facial expression which arises in the fascia over the parotid gland and, passing horizontally forward, superficial to the platysma, inserts onto the skin at the angle of the mouth.

scalenes

The scalene muscles are three paired muscles (anterior, middle and posterior), located in the lateral aspect of the neck. Collectively, they form part of the floor of the posterior triangle of the neck. The scalenes act as accessory muscles of respiration,and perform flexion at the neck.

splenius capitis

The splenius capitis (/ˈspliːniəs ˈkæpɪtɪs/) (from Greek spléníon, meaning 'bandage', and Latin caput, meaning 'head') is a broad, straplike muscle in the back of the neck. It pulls on the base of the skull from the vertebrae in the neck and upper thorax. It is involved in movements such as shaking the head.

Sternocleidomastoid

The sternocleidomastoid muscle is one of the largest and most superficial cervical muscles. The primary actions of the muscle are rotation of the head to the opposite side and flexion of the neck. The sternocleidomastoid is innervated by the accessory nerve.

sternohyoid

The sternohyoid muscle is a thin, narrow muscle attaching the hyoid bone to the sternum, one of the paired strap muscles of the infrahyoid muscles serving to depress the hyoid bone. It is innervated by the ansa cervicalis.

zygomaticus major

The zygomaticus major is a muscle of the human body. It is a muscle of facial expression which draws the angle of the mouth superiorly and posteriorly to allow one to smile.

zygomaticus minor

The zygomaticus minor is a muscle of facial expression. It originates from the zygomatic bone and continues with orbicularis oculi on the lateral face of the levator labii superioris and then inserts into the outer part of the upper lip. It draws the upper lip backward, upward, and outward and is used in smiling.

action of Sternocleidomastoid

bilateral: flexes the neck unilateral: laterally rotates the neck to the opposite side

action of Masseter

elevates and protracts the mandible

action of Levator Labii Superioris

elevates the upper lip, as in expressions of sadness or seriousness

epicranius

made of the frontalis + occipitalis connected by a large sheet of connective tissue called the Aponeurosis

origin of Depressor Anguli Oris

mandible (anterolateral surface of the body)

insertion of Masseter

mandible(lateral surface of ramus

insertion of Sternocleidomastoid

mastoid process of temporal bone

origin of Levator Labii Superioris

maxilla (inferior to infraorbital foramen)

insertion of Depressor Anguli Oris

muscles and skin in the lower lip near the angle of the mouth

insertion of Levator Labii Superioris

orbivularis oris and skin of the upper lip

action of Depressor Anguli Oris

pulls corners of the mouth inferior as in frowning

action of Zygomaticus major/minor

pulls the corners of the mouth posteriorly and superiorly, as in smiling

insertion of Zygomaticus major/minor

skin and muscle at the corner of the mouth

origin of Sternocleidomastoid

sternal head: manubrium of sternum clavicular head: clavicle(medial third)

origin of Masseter

zygomatic arch

origin of Zygomaticus major/minor

zygomatic bone