Muscles Of Head And Neck

Myology(Ⅲ )

Section3

Muscles of head and neck

一 . Muscles of head Facial muscles: Epicranius (occipitofrontalis) Frontal belly Occipital belly Galea aponeurotica Orbicularis oculi Buccinator Orbicularis oris Nasalis

Frontal belly of occitofrontalis

orbicularis oculi Levator anguli oris Orbicularis oris

Levator labii superioris

Depressor labii inferioris Depressor anguli oris

masticatory muscles Masseter ： Temporalis Origin － inferior border and medial surface of zygomatic arch Insertion － lateral surface of ramus of mandible and angle of mandible Masseter Temporalis ： Origin － temporal fossa Insertion － coronoid process of mandible action ： masseter, temporalis --- elevates mandible — close the mouth

masticatory muscles lateral pterygoid

medial pterygoid lateral pterygoid

action ： Medial pterygoid— elevates mandible—close the mouth

Lateral pterygoid—pull the head of mandible forwards--- open the mouth

medial pterygoid

二 . Muscles of neck 1. superficial group Platysma Sternocleidomastoid Origins: manubrium and medial1/3 of clavicle Insertion: mastoid process of temporal bone; Actions: acting alone, the head is inclined ipsilateral and the face is rotated to opposite side; acting together, they extend the head.

2. suprahyoid muscles Digastric

Anterior belly Posterior belly

Mylohyoid Stylohyoid Geniohyoid Action:elevate (raise) hyoid bone and depress mandible.

3. infrahyoid muscles sternohyoid omohyoid sternothyroid thyrohyoid Action: depress hyoid or larynx

4.The deep cervical muscles A. lateral goup scalenus anterior scalenus medius scalenus posterior

scalene fissure ： it is bounded by the scalenus anterior and medius and first rib ， it contains the subclavian a and brachial plexus.

4.The deep cervical muscles B. medial group ： longus colli longus capitis

action ： laterally flex the neck to the same side and rotate the cervical region of the vertebral column to the opposite side.