Post on 22-May-2015
description
transcript
THE MUSCULATURE OF THE HEAD
By: Dr. Pamela Josefina T. Fabie
Related mainly to the orbital margins and eyelids, the external nose and nostrils, the cheeks and mouth, the pinna, scalp and cervical skin.
MUSCLES OF FACIAL EXPRESSION
COMMON CHARACTERISTICS:
1) All are inserted into the skin of the face2) All are supplied by the muscular branches
of the facial nerve3) All produce facial expression
The craniofacial ,sucles receive theor innervatons from the braches of the FACIAL NERVE.
They are grouped as:1. Epicranial2. Circumorbital and Palpebral3. Nasal4. Buccolabial
I. EPICRANIAL MUSCLES
1. OCCIPITOFRONATALIS – covers the dome of the skull
1. Frontalis musclesThe muscle that covers the forehead. It has no bony attachment.
ORIGIN: anterior part of the galea aponeurotica
INSERTION: skin on the lower part of the forehead
ACTION: produce transverse wrinkles on the forehead as in surprise. It raises the eyebrows.
2. Occipitalis musclesA short and narrow muscle that arises from the occipital bone
ORIGIN: lateral 2/3 of the superior nuchal line
INSERTION: posterior part of the galea aponeurotica
ACTION: draw the galea aponeurotica backwards to fix and tense it.
2. TEMPOROPARIETALIS– variably developed sheet of muscle that lies between the frontal parts of the occipitofrontalis and anterior and superior auricular muscles
Temporoparietalis
II. CIRCUMPUBERTAL AND
PALPEBRAL MUSCLES
1. ORBICULARIS OCULI
A. PALPEBRAL PORTIONORIGIN: medial palpebral ligament and adjacent part of the maxilla
INSERTION: outer surface of the lateral palpebral margin
ACTION: close the eyelids as in sleeping and winkling
B. ORBITAL PORTION
ORIGIN: medial palpebral ligament, frontal bone and maxilla
INSERTION: medial palpebral ligament (no lateral attachment)
ACTION: helps close the eyelids and draw lateral part of lids medially. They are responsible for the “crow’s feet” usually seen at the lateral angles of the eye
C. LACRIMAL PORTION - aka HOMER’S MUSCLE or tensor
tarsi
ORIGIN: posterior lacrimal crest
INSERTION: tarsal plate
ACTION: compress lacrimal sac, forcing the tears into the nasal cavity through the naso-lacrimal duct
TENSOR TARSI
2. CORRUGATOR SUPERCILLI – - deep muscle blending with the upper portion of the orbicularis muscle
ORIGIN: fronto-nasal suture and frontal bone, and medial part of the supercilliary arch
INSERTION: skin on the medial half of the eyebrow
ACTION: throw the skin of forehead into folds as in frowning
3. LEVATOR PALPEBRAE SUPERIORIS
ORIGIN: lesser wing of the sphenoid bone just above the optic foramen
INSERTION: skin of the upper eyelid as well as the superior tarsal plate
ACTION: elevates the upper eyelid thereby opening the eyes
III. NASAL MUSCLES
ORIGIN: nasal bone and lateral nasal cartilage
INSERTION: skin at the root of the nose
ACTION: compress the nostril and depress the cartilage of nose
A. PROCERUS – small muscle overlying the basal bone (frowning)
ORIGIN: side of the bony aperture of the nose and the upper end of the canine eminence of maxilla
INSERTION: the aponeurosis of the cartilaginous part of the nose
ACTION: compress the nostrils a d depress the cartilage of the nose
B. NASALIS – aka COMPRESSOR NARES or PARS TRANSVERSUS
ORIGIN: nasal notch of the maxilla and the nasolabial groove
INSERTION: inferior border of the ala of the nose
ACTION: dilate the nostrils
C. DILATOR NARES
ORIGIN: medial fiber of the dilator naris muscle
INSERTION: mobile part of the nasal septum
ACTION: draw the septum downwards and to narrow the nostril
D. DEPRESSOR SEPTI NASI
IV. BUCCOLABIAL
MUSCLES
1.ELEVATORS, RETRACTORS and EVERTORS OF THE UPPER LIP Levator labii superioris alaque nasi Levator labii superioris Zygomaticus major and minor Levator anguli oris Risorius
ORIGIN: frontal nasal process
INSERTION: one slip goes to ala of the nose while the other goes to the orbicularis oris
ACTION: elevate the ala of the nose and the upper lip
A. LEVATOR LABII SUPRIORIS ALAQUE NASI
ORIGIN: infraorbital head, zygomatic head and angular head
INSERTION: upper lip
ACTION: elevate lateral par of upper lip. Contraction of infraorbital head gives expression of sadness. Contraction of infraorbital head gives expression of disdain or doubt
B. LEVATOR LABII SUPRIORIS
ORIGIN: zygomatic bone and arch
INSERTION: angle of the mouth
ACTION: elevate or draw angle of the mouth up and back as in laughing or smiling
C. ZYGOMATICUS MAJOR - Smiling muscle or muscle of
happiness
ORIGIN: zygomatic bone, medial to zygomatic major
INSERTION: skin on the nasolabial groove
ACTION: deepen the nasolabial groove as in sorrow
D. ZYGOMATICUS MINOR- gives the expression of pain or sorrow
ORIGIN: maxilla below the infraorbital foramen and the canine fossa of maxilla
INSERTION: fibers are directed downward, to be inserted to the angle of the mouth
ACTION: elevate angle of the mouth (also a muscle of happiness)
E. LEVATOR ANGULI ORIS OR CANINUS
ORIGIN: superficial fascia over the parotid
INSERTION: skin and mucosa of the angle of the mouth
ACTION: draw the angle of the mouth laterally, giving an expression of strain and stress
F. RISORIUS-lies horizontally across
the cheek. Gives the expression of irony or plasticity
2. DEPRESSORS, RETRACTORS and EVERTORS OF THE LOWER LIP
Depressor labii inferioris Depressor anguli oris mentalis
ORIGIN: base of the mandible, between mental protuberance and mental foramen
INSERTION: skin and mucosa of the lower lip
ACTION: draw the lower lip downward, as in ‘irony”
A. DEPRESSOR LABII INFERIORS
- a quadrilateral muscle; gives the expression of frowning
ORIGIN: oblique line of mandible
INSERTION: angle of the mouth
ACTION: depress the angle of the mouth
B. DEPRESSOR ANGULI ORIS or TRIANGULARIS
- gives the expression of sadness
ORIGIN: mandible below the lower incisor teeth and beneath oral mucosa
INSERTION: skin of chin
ACTION: elevate chin. It also causes trembling of the chin. It wrinkles the skin of the chin as in disdain or doubt.
C. MENTALIS MUSCLE
3.A COMPOUND SPHINCTER Orbicularis oris Accessory muscles to the orbicularis
oris incisivus superior and incisivus inferior
ORIGIN: buccinator muscle
INSERTION: upper lip- angle of the mouth; lower lip - mandible
ACTION: close the mouth in various ways such as closing, pressing against teeth, twisting and protruding
ORBICULARIS MUSCLE
- muscle that forms the sphincter around the mouth
BUCCINATOR MUSCLE
ORIGIN: outer surface of alveolar process of maxilla and mandible in the region of the molar teeth and pterygomandibular ligament
INSERTION: angle of the mouth blending with the orbicularis oris
ACTION: press the cheek against the teeth while chewing. Useful in mastication, whistling, sucking and blowing
PLATYSMA MUSCLE
ORIGIN: skin and superficial fascia of the pectoral and deltoid regions
INSERTION: directed upward and forward to be inserted into the lower border of the mandible
ACTION: retract and depress the angle of the mouth; Depress the mandible.
END