Head and Neck Anatomy PDF

Head and Neck JJ: [email protected] PSPanda PSPANDA References Structure of These Slides Gray’s anatomy Head Upper Respiratory Tract and Pharynx Moore and Dalley B...

Head and Neck JJ: [email protected] PSPanda PSPANDA References Structure of These Slides Gray’s anatomy Head Upper Respiratory Tract and Pharynx Moore and Dalley Bones Overview Netter’s Atlas of Human Muscles Ear Anatomy Nasal Cavity Teachmeanatomy Neck Oral Cavity Instant anatomy Relations Pharynx Course book, tutors, lectures Bones Larynx Muscles Cross Section and Fascia Triangles of Neck Head and Neck Vasculature Nerves The Head Bony Bits The Skull Intramembranous ossification Joined by sutures (fibrous joints) which fuse together in adulthood Composed of neurocranium (which houses brain hence neuro) and viscerocranium (the face)  The Skull Appreciate! Don’t worry we’ll break it down These images are from: https://www.instantanat omy.net/index.html Neurocranium Composed of 8 bones: 4 midline (frontal, ethmoidal, sphenoidal, occipital) and 2 bilateral pairs (temporal, parietal) Roof/calvarium (frontal, occipital, parietal), floor/basicranium (frontal, sphenoid, ethmoid, occipital, parietal, temporal) Frontal Bone Glabella tap: Parkinson’s Tap on glabella (of frontal bone) - normal reflex is to blink but eventually you stop In Parkinson’s patients continue to blink Parietal Bone Occipital Bone Ethmoid Bone  Ethmoid Bone Where: roof of nasal cavity, between 2 orbital cavities (eye). Part of anterior cranial fossa Anatomy Forms ethmoidal labyrinths which are composed of: ○ Lateral sheet (orbital plate) ○ Medial sheet (superior and middle conchae - more in nose) Labyrinths unite at cribriform plate which has ○ Holes for olfactory nerve (CNI) fibres ○ Crista galli - for attachment of falx cerebri (dura mater) Foramen caecum - emissary veins Perpendicular plate forms part of nasal septum Provides link between: Cranial and nasal (cribriform plate/foramen caecum) → CSF leak causes nasal drip Nasal and orbit → air causing orbital emphysema Sphenoid Bone  Sphenoid Bone Located in middle cranial fossa around back of nasal cavity/orbit/temple Composed of body, greater/lesser wings, pterygoid process Body: Sella turcica (depression) contains Superior view hypophyseal fossa where pituitary gland sits ○ Bound by tuberculum sellae (anterior) and dorsum sellae (posterior) Anterior/posterior clinoid processes x2 Chiasmatic groove/sulcus is formed by optic chiasm Lesser wing Forms division between anterior/middle cranial fossa Borders optic canal with body Posterior view  Sphenoid Bone Greater wing Foramen rotundum - V2 Foramen ovale - V3 Foramen spinosum - middle meningeal vessels Spine provides attachment for sphenomandibular l. And tensor veli palatini Superior view Pterygoid processes Medial pterygoid plate - contains pterygoid hamulus which acts as a pulley for tensor veli palatini and attachment for pterygoidmandibular raphe Lateral pterygoid plate - attachment of medial/lateral pterygoid muscles Pterygoid canal (runs horizontally through root of pterygoid process) opens into pterygopalatine fossa Posterior view Temporal Bone  Temporal Bone Squamous Temporalis muscle Petrotympanic fissure - chorda tympani Zygomatic Process articulates with zygomatic bone Lateral surface - masseter m. Tympanic External auditory meatus (i.e. your ear) Articulates with head of mandible to form temporomandibular joint (TMJ) Styloid Process Stylomandibular l. Of TMJ Styloglossus m. Petromastoid Mastoid process - sternocleidomastoid, posterior belly of digastric, splenius capitis Mastoid Air cells Petrous part - inner ear and boundary between middle/posterior cranial fossa Neurocranium Roof Mainly made up of frontal, 2x parietal, and occipital bones Sutures: coronal, sagittal, lambdoid Bregma (front), lambda (back) Pterion is point between sphenoid (greater wing), temporal, frontal, parietal bones. Anterior division of middle meningeal a. Runs under here so trauma can cause extradural haematoma Neurocranium - Floor/basicranium Made up of frontal, ethmoidal, sphenoid, temporal, parietal, occipital bones Divided into anterior, middle, posterior cranial fossa at: lesser wing of sphenoid petrous part of temporal bone Contains the cranial foramena  Cranial Foramena Bare minimum: (try learn them all) Formen CN Other Cribriform Plate 1 Optic canal 2 Ophthalmic a. Superior orbital fissure 3, 4, 5(1), 6 Sup ophthalmic v. Foramen rotundum 5(2) Foramen ovale 5(3) Foramen spinosum Middle meningeal a./v. Carotid canal Internal carotid a. Internal acoustic meatus 7, 8 Jugular foramen 9, 10, 11 Inferior petrosal and sigmoid sinus → IJV Hypoglossal canal 12 Foramen magnum Medulla oblongata, meninges, vertebral a. Viscerocranium Nasal Bone Vomer Lacrimal Bone Zygomatic Bone Contains maxillary, frontal, and temporal processes where it articulates Zygomaticofacial foramen - zygomaticofacial n. and vessels Maxilla Maxilla Forms roof of palate At the front: Incisive canals are on either side of the incisive fossa ○ Greater palatine vessels and nasopalatine nerves travel between the oral/nasal cavities At the back: Posterior nasal spine and posterior margin of horizontal palates ○ Attachment of soft palate Palatine canal (from pterygopalatine fossa) forms: ○ Greater palatine foramen - greater palatine n. and vessels to supply the hard palate ○ Lesser palatine foramen - lesser palatine n. and vessels to supply the soft palate Mandible  Mandible Important parts Made up of body and ramus Condylar process forms temporomandibular joint (TMJ) with temporal bone Coronoid process - attachment of temporalis m. Mandibular foramen forms mandibular canal which finishes as mental foramen ○ Inferior alveolar n. (from V3) supplies teeth as travels through this and turns into the mental n. as it exits to supply skin of chin ○ Inferior alveolar vessels also ttravels through Mylohyoid line forms mylohyoid groove ○ Lingual n. ○ N. to mylohyoid  Mandible Other bits: Alveolar border = where teeth are Mandibular symphysis = midline, and encloses mental protuberance Superior/inferior mental spines on inside of chin Sublingual and submandibular fossa Retromolar triangle Neck of condylar process - lateral pterygoid Lingula - sphenomandibular l.  Temporomandibular Joint (TMJ) Synovial joint Formed by: head of condylar process (mandible) and tubercle of tympanic part of (temporal bone) Ligaments: Lateral, sphenomandibular, stylomandibular Articular surfaces are covered with fibrocartilage and divided into 2 by articular disc Muscles of mastication: Masseter, temporalis, medial/lateral pterygoid Develop from 1st pharyngeal arch ALL INNERVATED BY mandibular nerve (V3) All muscles elevate ○ Except lateral pterygoid (oriented horizontally onto pterygoid process) which instead moves side to side + protracts ○ Temporalis m. (deep temporal n.) also retracts jaw by attaching to condylar process  Temporal, Infratemporal, Pterygopalatine Fossa Temporal Fossa: Temporalis m. Deep temporal n. and artery Middle temporal a. (from maxillary a.) Zygomaticotemporal branch of V2 Feeds into Infratemporal Fossa: between ramus of mandible and wall of pharynx Feeds into Pterygopalatine Fossa: under zygomatic arch Communicates with nose, eye, middle cranial fossa Maxillary n. (V2) and artery Pterygopalatine ganglion