Face and Scalp Anatomy PDF

Summary

This document provides detailed information on the anatomy of the face and scalp, including the structure, function, and innervation of various muscles, as well as blood and lymph supplies. It also discusses common conditions and injuries related to this area of anatomy.

Full Transcript

Scalp and Face Dr. Saima Tasneem Face Index of mind Boundaries of Face Extends superiorly from the adolescent position of hairline Inferiorly to the chin and the base of the mandible On each side to the auricle. The f...

Scalp and Face Dr. Saima Tasneem Face Index of mind Boundaries of Face Extends superiorly from the adolescent position of hairline Inferiorly to the chin and the base of the mandible On each side to the auricle. The forehead is common to both the face and the scalp. Skin Facial skin is very vascular. Rich in sebaceous glands Rich in sweat glands. Laxity of skin facilitates rapid spread of oedema. Boils in the nose and ear are acutely painful due to the fixity of the skin to the underlying cartilages. Facial skin is very elastic and thick because the facial muscles are inserted into it. Face SUPERFICIAL FASCIA contains: Facial muscles which are inserted into the skin Vessels and nerves, to muscles & skin Variable amount of fat. Fat is absent from the eyelids but well-developed in the cheeks Deep fascia is absent from the face, except over the parotid gland where it forms the parotid fascia, and over the buccinator where it forms the buccopharyngeal fascia. Facial Muscles Subcutaneous muscles. These muscles are inserted into skin, and bring out various facial expressions. Facial muscles have small motor units. Embryologically, they develop from the mesoderm of the second branchial arch, and are, therefore, supplied by the facial nerve Facial Muscles Functionally facial muscles are regarded as regulators of 3 openings situated on the face Palpebral fissures Nostrils Oral fissure. Face Sensory supply of face is trigeminal 5th cranial nerve Motor supply to muscles of facial expression Facial nerve 7th cranial N. trigeminus (CN V) V1; N.ophthalmicus N.occipitalis major (C2) N.occipitalis V2; N.maxillaris minor (C2) V3; N.mandibularis Pl.cervicalis Sensory Nerve Supply Ophthalmic division: Forehead & scalp; frontal & ethmoidal sinus; upper eyelid & its conjunctiva; cornea & dorsum of nose Maxillary division: skin and mucous membrane of lower eyelid & its conjunctiva; cheeks & maxillary sinus; nasal cavity & lateral nose; upper lip; upper molar, incisor & canine teeth & associated gingiva & superior palate Mandibular division: floor of oral cavity; external ear; lower lip; chin; anterior 2/3 of the tongue & lower molar, incisor & canine teeth & the associated gingiva Clinical Anatomy Sensory Innervation of Face Sensory distribution of 5th cranial nerve is cause of headache in conditions involving Nose (common cold, boils) Paranasal air sinuses (sinusitis) Infections and inflammations of teeth and gums Refractive errors of the eyes Trigeminal neuralgia Sudden, severe facial pain. Sharp shooting pain or like having an electric shock in the jaw, teeth, or gums. Maxillary and mandibular division of trigeminal nerve are involved In most cases, trigeminal neuralgia affects just one side of the face, with the pain usually felt in the lower part of the face. Motor Nerve Supply of Facial Muscles Temporal—frontalis, auricular muscles, orbicularis oculi Zygomatic—orbicularis oculi (lower eyelid part). Buccal—muscles of the cheek and upper lip. Mandibular—muscles of lower lip. Cervical—platysma. Infranuclear Lesion of Facial Nerve Occurs at stylomastoid foramen Paralysis of upper and lower quarters of face on same side Face is asymmetrical and drawn up to normal side. No motion on affected side Wrinkles disappear from the forehead. Eye cannot be closed leading to keratitis. When smiling mouth draws to normal side. During mastication, food accumulates between the teeth and the cheek. Drooling of saliva Supranuclear Lesion of Facial Nerve Only the lower quarter of the opposite side of the face is paralyzed. Muscles of Facial Expression Muscles of the Eyelids/Orbital Openings 1 Orbicularis oculi 2 Corrugator (Latin to wrinkle) supercilii 3 Levator palpebrae superioris Muscles of the Nose 1 Procerus 2 Compressor naris 3 Dilator naris 4 Depressor septi Muscles of Facial Expression Muscles around the Mouth Orbicularis oris Buccinator (Latin cheek) Levator labii superioris alaeque nasi Zygomaticus major & minor Levator labii superioris Levator anguli oris Depressor anguli oris Depressor labii inferioris Mentalis (Latin chin) Risorius (Latin laughter) Occipitofrontalis Occipitofrontalis is one of the muscles of scalp. It arises from two distinct parts: Occipital part (belly) Frontal part (belly) The frontal part lifts the eyebrow and the upper eyelid producing horizontal wrinkles on the forehead. The Orbicularis Oculi –Constructed of three parts, the palpebral, orbital and lacrimal. –The palpebral area lies at the centre of this sphincter muscle and forms the eyelids –Orbicularis Oculi muscle allows us to open and close the eyelids. –Closes eye in blinking and sleep Orbicularis Oculi Dilates lacrimal sac for the sucking of lacrimal fluid into lacrimal sac Corrugator Supercilii Small, narrow, pyramidal muscle Located at the medial end of the eyebrow, beneath frontalis and just above orbicularis oculi muscle. When contracted it pulls the skin of the eyebrow downward and medially. Produces vertical wrinkles of the forehead. Nasalis Sphincter like muscle of the nose whose function is to compress the nasal cartilages. It is the muscle responsible for "flaring" of the nostrils. Levator Labii Superioris Raises the upper lip. Involved in movements such as facial expressions, actions of disgust, expressions of sadness, nasal flaring, retching (vomiting) and to show oral content. Origin is on the lateral aspect of the nose and extends to the zygomatic bone. Levator Anguli Oris The happy muscle, making the corners of our mouth turn upwards into a smile. Zygomaticus Major & Minor Both muscles are involved in elevating the upper lip to generate a smile. Risorius A very thin and delicate muscle that pulls the lips horizontally creating a large, but insincere smile. Orbicularis oris The circular muscle around our mouth Brings our lips together. Action –closes the mouth Depressor Labii İnferioris This muscle pulls down the bottom lip allowing us to sulk. Depressor Anguli Oris This muscle lowers the corners of our mouth. It contracts when we are sad and bored Buccinator ‘Trumpeter muscle’ Buccinator’s role is to puff out the cheeks and prevent food from passing to the outer surface of the teeth during chewing. (blowing, whistling) Mentalis Sometimes called the ‘pouting muscle’, contraction of the Mentalis raises and thrusts out the lower lip to make us pout Platysma Origin– upper part of pectoral and deltoid fascia Insertion– base of mandible, skin of lower face and lip Action– Platysma stretches the skin of the face and neck Blood supply of face Arterial supply- Facial artery a branch of external carotid artery Passes through the submandibular region before entering the face Anterior branches are large Inferior labial, to the lower lip. Superior labial, to the upper lip and the anteroinferior part of the nasal septum. Lateral nasal, to the ala and dorsum of the nose. The posterior branches are small and unnamed Venous Drainage of Face Dangerous area of face The facial veins and deep connecting veins are devoid of valves, making an uninterrupted passage of blood to the cavernous sinus. Squeezing the pustules or pimples in the area of the upper lip or side of nose or even the cheeks may cause infection which may be carried to the cavernous sinus leading to its thrombosis Examining the Facial Nerve Frontalis: Ask the patient to look upwards without moving his head, and look for the normal horizontal wrinkles on the forehead. Dilators of mouth: Showing the teeth Orbicularis oculi: Tight closure of the eyes Buccinator: Puffing the mouth and then blowing forcibly as in whistling Lymph Glands Submental Submandibular Buccal and mandibular Preauricural Occipital Scalp Boundaries of scalp Extends from the superciliary arches anteriorly to the external occipital protuberance and superior nuchal lines posteriorly Down to the ears and zygomatic arches laterally SCALP Skin Connective Aponeurosis Loose areolar Pericranium tissue tissue The scalp is multilayered structure The first three layers are intimately bound together and move as a unit. Layers of Scalp SCALP S (Skin): S C Thick and hairy A L Firmly attached to the P epicranial aponeurosis through dense fascia Abundant sebaceous glands Sebaceous cysts are common SCALP C (Connective tissue): Fibrous and dense containing S blood vessels and nerves C Binds skin to subjacent aponeurosis Wounds bleed profusely as blood vessels are prevented from retraction by fibrous tissue. Bleeding is stopped by applying pressure against the bone Subcutaneous hemorrhages are not extensive due to dense fascia Inflammation causes little swelling but more painful SCALP A (Aponeurosis): Anteriorly frontal belly and posteriorly occipital belly of occipitofrontalis muscle Frontal belly originates from skin of forehead and mingled with orbicularis oculi muscle Occipital belly originates from lateral 2/3 of superior nuchal line It gaps if cut transversely and should be stitched SCALP - L (Loose areolar tissue): Extends anteriorly into the eyelids as frontalis has no bony attachment Posteriorly to superior nuchal line On each side to superior temporal line Bleeding causes generalized swelling of scalp Dangerous layer of scalp-emissary veins open here and carry any infections inside the brain (venous sinus) Bleeding leads to black eye Caput succedaneum in new born Arterial Supply of Scalp In front of the auricle, the scalp is supplied from before backwards by the: Supratrochlear Branches of ophthalmic art a Supraorbital branch of int carotid Superficial temporal arteries branch of the external carotid artery. Behind the auricle, the scalp is supplied from before backwards by the: Posterior auricular Occipital (tortuous) arteries, both of which are branches of the external carotid artery. Lympahtic Drainage of Scalp Lymph vessels in anterior part of scalp and forehead drain into the submandibular lymph nodes. Drainage from lateral part of scalp above the ear is into the superficial parotid (preauricular) nodes. Lymph vessels in the part of the scalp above and behind the ear drain into the mastoid nodes. – Vessels in the back of the scalp drain into the occipital nodes. Black Eye Collection of blood in the layer of loose connective tissue causes generalized swelling of the scalp. The blood may extend anteriorly into the root of the nose and into the eyelids (as frontalis muscle has no bony origin) resulting in black eye. SCALP P (Pericranium, periost): Is the periosteum of skull S Loosely attached to surface of bone C but is firmly adherent to the sutures A L Injury deep to it take the shape of P bone(cephalhaematoma) Scalp injury- should be stitched because healing is better Birth Injuries Caput succedaneum cephalhaematoma

Use Quizgecko on...
Browser
Browser