Anatomy - Neck Flashcards
PREVERTEBRAL MUSCULATURE
Muscles
- Rectus Capitis Anterior RCA and RCL lie side-by-side
* Lat mass of atlas to front of foramen magnum - Rectus Capitis Lateralis
- Lat mass of atlas to jugular process of occipital bone - Longus capitis
- Anterior tubercle C3-6 to basiocciput
- Insert in line with Scalenus Anterior - Longus Colli 3 sets of fibres
- Upper - Anterior tubercle atlas to TP C3-5
- Middle - C2-4 bodies to TP C7-T3
- Lower - T1-3 bodies to TP C5-6
PREVERTEBRAL MUSCULATURE
Nerve supply
Nerve supply:
RCA/RCL - Anterior ramus of C1
Longus capitis - Anterior rami C1-4
Longus colli - Segmental supply from anterior rami
PREVERTEBRAL MUSCULATURE
Draw
Lingual Nerve
Course (& relations in infratemporal fossa)
Cervical Plexus
Definition & location
Cervical Plexus:
- Anterior rami of C1-5
- Deep to Prevertebral fascia, lies on surface of scalenus anterior (in series with brachial plexus)
- Proprioceptive fibres to SCM (C2-3), Trapezius (C3-4)
Cervical Plexus
Branches (Muscular)
Cervical plexus nerves - muscular
- C1 loop (hitchhiking) - joins XII -> superior root of ansa, and thyrohyoid & geniohyoid
- C2/3 & C3/4 - to SCM & trap (mostly proprioceptive)
- Inferior root of ansa cervicalis - C2/3, spirals lateral to IJV
- Phrenic - C4 (3/5) - over scalenus anterior, behind PVF
Cervical Plexus
Branches (Cutaneous)
Cervical plexus nerves - cutaneous
- Lesser occipital - C2 - hooks around XI, skin post neck / sup nuchal line
- Great auricular nerve - C2/3 - skin AOM / parotid fascia, auricle - cranial & lower lateral
- Transverse cervical nerve - C2/3, midline of neck chin - sternum
- Supraclavicular - C3/4 - lower neck / shoulder
Supra & Infra Hyoid muscles
Muscles
Origin & Insertion
Innervation
Suprahyoid muscles:
- Mylohyoid- Mylohyoid line to hyoid and midline raphe, post 1/4 into body hyoid
- N. to Mylohyoid (V3) from IAN - Geniohyoid- genial tubercle to body of hyoid (deep to MH)
- C1 direct branch (hitch-hiking XII) - Digastric- medial mastoid tip to lesser horn of hyoid to digastric fossa (inf surface of mandible)
- ABD - N to MH (V3), PBD - VII - Stylohyoid- High/posterior styloid to lesser horn of hyoid (straddles PBD)
- VII
Infrahyoid muscles:
- Sternohyoid- Hyoid to undersurface of manubrium
- Omohyoid- Hyoid, intermediate tendon, transverse scapular lig
- Sternothyroid- deep to S/H, oblique line of thyroid cartilage to sternum
- Thyrohyoid
- 1-3 supplied by ansa, 4 by C1 fibres (hitch-hiking XII)
Layers of Cervical fascia
Superficial
Superficial
- Encases platysma
- Extends to the face as SMAS layer, up to zygomatic arch
Layers of Cervical fascia
Deep
Deep
1. Superficial layer-
a. 2 glands (SM/Parotid, separated by Stylomandibular lig
b. 2 muscles- SCM and Trapezius
c. 2 spaces- supraclavicular, suprasternal space of Burns
d. Att to - hyoid, sup nuchal line, mandible, zygomatic arch, spine scapula, lat clavicle, jug notch.
e. Forms stylomandibular lig, sling for omohyoid to clavicle (see fig), forms clavipectoral fascia (pierced by EJV)
2. Middle layer-
a. Muscular- surrounds infrahyoid straps. Hyoid - clavicle/sternum
b. Visceral- surrounds trachea/thyroid/oesophagus/pharynx. Includes BP fascia
- Continuous with aortic arch and fibrous pericardium
3. Deep layer-
a. Alar - BOS-T2 (joins with visceral layer of MLDCF)
b. Prevertebral - BOS-Coccyx. Invests phrenic, brachial plexus, vertebral/subclavian vessels (not vein) and gives rise to Axillary
Sheath
Pierced by 4 br of cervical plexus (Great auricular, Lesser Occipital, Transverse Cervical, supraclavicular)
Cervical Fascia
Label layers and structures:
Deep Neck Spaces
- Entire Neck
Boundries & Contents
Entire neck
- Superficial - Deep to platysma. Contains fat, LNs, EJV
- Retropharyngeal - Visceral MLDCF in front, alar DLDCF behind. Down to T2 where these layers meet.
X-Ray measurements 7, 14, 21:
- C2 <7mm
- C6 <14mm (child <15yrs)
- C6 <21mm (adult)
3. Danger - BOS —> diaphragm. Between alar and prevertebral region
4. Visceral Vascular - Carotid sheath formed by contributions from each layer of DCF
5. Prevertebral - BOS —> coccyx - Prevertebral muscles - longus capitis/colli, scalenes - ant/mid/post
- Nerves - Phrenic, brachial plexus
- Vessels - Vertebral artery/vein
Deep Neck Spaces
- Suprahyoid
Boundries & Contents
Above Hyoid
- Peritonsillar - Tonsil capsule, sup constrictor, ant/post tonsil pillars
- Parapharyngeal - see separate card
- Parotid - enclosed within the parotid fascia (splitting of the SLDCF)
- Submandibular
- Subdivided to the Sublingual and Submandibular by the mylohyoid
- Sublingual: mandible, mylohyoid, genioglossus/geniohyoid, FOM mucosa
- Contents - XII, Lingual N, IX, Lingual artery/vein, SLG, SM duct and deep part of SMG
- Submandibular: mandible, hyoid, mylohyoid, SLDCF
- Contents - SM gland, facial artery/vein, LNs, fat, digastric muscles - Temporal - continuous w. masticator, temporalis muscle divides into superficial & deep
- Masticator
- SLDCF splits to encompass the muscles of mastication:
- Contents - LP, MP, masseter, IAN, body / ramus mandible
Deep Neck Spaces
- Infrahyoid
Boundries & Contents
Below Hyoid
- Pretracheal
- aka anterior visceral space, enclosed by visceral MLDCF, thyroid cart -> arch aorta - Suprasternal space of Burns
- Supraclavicular
Carotid Shealth
Define
Relationships
Contents
Arch of aorta to skull base
Comprised of fascia from all 3 layers of deep cervical fascia
Relationships:
Medial - pharynx
Lateral - deep lobe parotid, styloid apparatus
Anterior - ITF
Posterior - cervical SNS trunk and prevertebral fascia
Contents:
- ICA
- IJV
- X- lies deep in the groove between the IJV and ICA
Carotid Sheath
Relationship to Lower Cranial Nerves
Lower Cranial Nerves:
IX - Emerges between IJV/ICA and curves medially between forks of ICA/ECA
X - Travels within carotid sheath, deep in groove between IJV/ICA
XI - Emerges between IJV/ICA and curves laterally anterior to IJV
- 90% in front of IJV, 5% behind, 5% through
XII - Emerges from hypoglossal canal medial to sheath
- Curls down behind inferior vagal ganglion and forward around ICA/ECA deep to IJV
Rules:
- Always arteries deep, veins superficial
- Runs just above greater horn of hyoid and passes forward on hyoglossus (deep to mylohyoid)
Structures running between ECA & ICA bifurcation
Passing between the forks of the ICA/ECA:
- Styloid process and stylohyoid lig
- Styloglossus and Stylopharyngeus
- CN IX
- Pharyngeal branch of CN X
- Tract of a branchial fistula
PARAPHARYNGEAL SPACE
Boundaries
Divisions
Def: An inverted pyramid shape
Potential space lateral to upper pharynx, filled with fat and areolar tissue
Boundaries
Superior (base) - base of skull (temporal/sphenoid)
Inferior (apex) - junction of digastric tendon with lesser horn of hyoid
Anterior - Pterygomandibular raphe and medial pterygoid fascia
Posterior - Pre-vertebral fascia
Medial - Buccopharyngeal fascia overlying sup constrictor and pharyngobasilar fascia. Fascia from TVP to medial pterygoid
Lateral - Fascia overlying medial pterygoid, mandibular ramus, PBD and deep lobe of parotid
Division is by the Styloid process
tensor-vascular-styloid fascia
- Prestyloid - Fat, deep lobe parotid, LNs, Styloglossus, Stylopharyngeus, V3 branches, TVP, LVP, IMA, asc palatine a, asc pharyngeal a
- Post-styloid - Cartoid sheath (ICA, IJV, X), SNS trunk, IX, XI, XII, IMA, paraganglionic tissue
PARAPHARYNGEAL SPACE
Communcations
Pathology
Communications
Medial - peritonsillar space
Anterolateral - Masticator space
Posteromedial - Retropharyngeal space
Inferomedial - Submandibular space
Lateral - Parotid space
Posterior - Carotid sheath contents
Superior - ITF
Pathology:
80% benign, 20% malignant (mostly salivary)
Temporal Fossa
Boundries
Superficial temporal line
Contents
Boundaries:
Superiorly - by the superior temporal line.
Inferiorly - zygomatic arch (arbitrary designation)
Floor - bones of the lateral aspect of the skull, including a portion of the frontal, GW sphenoid, the temporal, and the parietal bones
Separated inferior from infratemporal fossa by the infratemporal crest of the greater wing of sphenoid
Superior temporal line:
Anteriorly - Zygomatic process of the frontal bone
Arches posteriorly over the parietal bone before descending to the temporal bone, where it blends into the zygomatic process
Attachment of temporalis fascia
Vertical groove on squamous temporal bone = superficial temporal vessels
Contents:
Temporalis muscle - attaches superiorly to inferior temporal line
INFRATEMPORAL FOSSA
Boundaries
Contents
A space lying beneath the base of skull between side wall of pharynx and ramus of mandible
Boundaries
Superior - IT surface of greater wing of sphenoid, Squamous temporal bone
- Continous with temporal fossa laterally (infratemporal crest marks this transition)
Inferior - Opens into the neck
Anterior - Posterior surface of maxilla and IOF
Posterior - Upper carotid sheath
Medial - Lateral surface of lateral pterygoid plate, TVP/LVP/superior constrictor, pterygomaxillary fissure (connects to PPF)
Lateral - Ramus of mandible and its coronoid process
Contents:
Medial pterygoid
Lateral pterygoid
Insertion of temporalis into coronoid process
Internal maxillary artery
Pterygoid venous plexus
V3 and branches (+ otic ganglion, chorda tympani)
PSAN (of V2)
MUSCLES OF MASTICATION
Origins & insertions
1. Medial pterygoid
- Origin
- Deep head: Medial surface LPP, fossa between MPP/LPP
- Superficial head: maxillary tuberosity and pyramidal process of palatine bone
- Insertion
- Angle of mandible (broad insertion)
2. Lateral pterygoid
- Origin
- Upper head - Infratemporal surface of skull (GW sphenoid)
- Lower head - Lateral surface of LPP
- Insertion
- Pterygoid fovea (beneath medial end of mandibular head)
- Articular disc and capsule of TMJ
3. Temporalis - Origin - Temporal fossa
- Insertion - Coronoid process and down ramus to buccinator insertion
4. Masseter - Origin - Zygomatic arch
- Insertion - 3 heads of masseter fuse anteriorly
- Posteriorly they diverge from one another
- Superficial - broad attachment - body, angle, ramus
- Intermediate - ramus
- Deep - ramus
- Between the heads: sup / intermed = masseteric artery, intermed / deep = masseteric nerve
Int Maxillary Artery
Parts & their boaders
Terminal branch of ECA (with superficial temporal a.)
Winds around neck of mandible and passes fwd between neck and sphenomandibular lig
3 parts: before, on and beyond lateral pterygoid muscle
Int Maxillary Artery
1st part
1st part: all through bony foramina
- Inferior alveolar a. - mandibular foramen
- Middle meningeal a. - foramen spinosum
- Accessory meningeal a. - foramen ovale
- Deep auricular a. - through bony-cartilagenous junction of EAC (tympanosquamous fissure - schultz notes)
- Anterior tympanic a. - petrotympanic fissure
Int Maxillary Artery
2nd part
2nd part: muscular branches
- Medial pterygoid
- Lateral pterygoid
- Temporal
- Lingual Nerve branch (check)
- Buccal Nerve branch
Int Maxillary Artery
3rd Part
3rd part: all through bony foramina in PPF
- Posterior superior alveolar a.- foramina in posterior wall of maxilla
- Greater palatine a.- greater palatine foramen
- Pharyngeal a.- Palatovaginal canal
- A. of Vidian canal- Vidian canal
- Infraorbital a - infraorbital foramen
Artery then leaves sphenopalatine foramen, changing its name
Pterygopalatine Fossa
Draw structure and communications
Pterygopalatine Fossa
Draw structure and communications & contents
Pterygopalatine Ganglion
Branches
Branches of the Pterygopalatine Ganglion:
- Nasopalatine N - SP foramen
- Septum + incisive gum of hard palate (descends down incisive foramen) - Lat Post Sup Nasal Ns - SP foramen
- Postersup quadrant of LNW - Greater Palatine N - GP foramen/canal (junction of maxilla and palatine bone)
- Mucosa of hard palate
- Nasal branches - posteroinf quadrant LNW + med wall max sinus - Lesser Palatine Ns - Lesser palatine foramina (behind GPN)
- Soft palate and tonsil mucosa - Pharyngeal N - Palatovaginal canal
- Nasopharynx mucous membrane - Orbital branches - IOF
- Orbital periosteum, orbitalis muscle
- Sphenoid/ethmoid sinuses
Pterygopalatine Fossa
Boundries
Lies between back of maxilla and pterygoid process of sphenoid
Boundaries:
- Posterior - sphenoid bone - a. root of pterygoid process (incl Vidian Canal), b. greater wing (incl Foramen Rotundum)
- Medial - palatine bone (incl notch for SP foramen)
- Anterior - posterior wall of maxilla - leads to IOF
- Roof - a. body of sphenoid, b. orbital process of palatine bone
- Lateral - pterygomaxillary fissure (leads to ITF)
Pterygopalatine fossa
Contents
Contents:
- V2
- Meningeal branch (to MCF)
- Zygomatic Nerve (arises in PPF and runs to IOF above V2), takes the secretomotor fibres from the ganglion (pass to lacrimal gland via Lacrimal branch of V1)
- Post Sup Alveolar N - Exits via Pterygomaxillary Fissure to posterior surface of maxilla
- V2 exits through IOF to become ION
- Ganglionic branch - Pterygopalatine Ganglion
- Connected to V2 by short trunk (inf/med to V2)
- Only cell bodies are PSNS (SNS and sensory fibres ‘relay station’)
- Autonomic root is Vidian N (PSNS- GSPN, SNS- ICA plexus via DPN)
- Fibres arise in Superior Salivary Nucleus - Maxillary Artery 5 branches accompany the 5 nerves of the PPG
- Vessels lie in front of nerves
Tongue
Definition, parts, papillae, folds
Mass of skeletal muscle with midline fibrous septum covered by mucous membrane
- Keratinising stratified squamous epithelium
Parts of the tongue:
- Dorsum, tip, ventral surface, base (BOT is oropharynx not oral cavity)
Papillae:
- Filiform- velvety appearance
- Fungiform- discrete pink pinheads (bears the taste buds)
- Circumvallate- 12, form a V in front of sulcus terminalis (marks division of oral cavity and oropharynx
Folds:
Median glossoepiglottic, lateral glossoepiglottic
Tongue
Muscles
Muscles:
1. Intrinsic x4 shape no bony attachments
- longitudinal (sup/inf), vertical, transverse
2. Extrinsic x 4 position
- Genioglossus - bulk of tongue. Genial tub to mucous memb + hyoid (i.e. geniohyoglossus)
- Hyoglossus - length of greater horn/body of hyoid (free ant + post borders)
- Styloglossus - low/ant styloid to interdig with hyoglossus
- Palatoglossus - undersurface of palate to interdig with styloglossus
Tongue
Blood supply
& Course of Lingual Artery
Blood supply:
Lingual A. - above greater horn of hyoid
- Dorsal lingual branches to posterior tongue
Asc Pharyngeal, tonsil branches of Facial- small contributions
Lingual v. - tributaries run with Lingual a.
Deep Lingual v. (visible in FOM) + sublingual v. — vena comitants of XII
Tongue
Nerve supply
Nerve supply:
Anterior 2/3 - sensation- Lingual N., Taste- chorda tympani
Posterior 1/3 - IX (sensation + taste), X (internal branch of SLN- ant valleculla)
Motor - all CN XII except palatoglossus (pharyngeal plexus)
** taste travels to nucleus tractus solitarius
Tongue
Embryology
Embryology:
Appears during Week 4 - as the tuberculum impar.
2 lateral swellings appear either side of the tuberculum —> fuse to form the midline fibrous septum (Arch I)
Base of tongue is formed from the hypobranchial eminence (Arch III). This joins with the lateral swellings at the sulcus terminalis to form the tongue
Tongue muscles derived from suboccipital myotomes (ie not supplied by branchial arch nerves - XII instead)
Migrate forward into the sac of mucous membrane derived from arches I, III, IV
Mucosa of the upper aerodigestive tract
Definintion
Mucosa definition:
Mucosa / mucous membrane is lining consisting of epithelium and an underlying connective tissue (lamina propria)
Mucosa of the upper aerodigestive tract
Nose
Nasopharynx
Nasal cavity
Vestibule = keratinising stratified squamous epithelium
Nasal cavity = ciliated pseudostraified columnar epithelium, also contains goblet cells
Olfactory epithelium = olfactory cells, supporting cells, basal cells, brush cells
Nasopharynx
Ciliated pseudostraified columnar epithelium
Adenoid = Ciliated pseudostraified columnar epithelium
Mucosa of the upper aerodigestive tract
Oral cavity
Oropharynx
Hypopharynx
Oral cavity
Masticatory surfaces: gingiva, hard palate, dorsum of tongue ant 2/3 (ectodermal origin) = keratinising stratified squamous epithelium
Other surfaces = non-keratinising stratified squamous epithelium (eg. labial, buccal, alveolar)
Specialised mucosa: Filiform papillae = tips are partially keratinised, Fungiform/foliate papillae = non-keratinised
Oropharynx
Palatine + lingual tonsils = non-keratinising stratified squamous epithelium
Tonsil crypts = lymphoepithelium (single layer squamous epithelium)
Dorsum of tongue (post 1/3) / circumvalate papilla (Endodermal origin) = non-keratinising stratified squamous epithelium
Hypopharynx
Non-keratinising stratified squamous epithelium
Mucosa of the upper aerodigestive tract
Larynx
Trachea
Bronchioles
Oesophagus
Larynx
Cilated pseudostratified columnar epithelium EXCEPT
Vocal folds = stratified squamous epithelium (transition point is superior and inferior arcuate line)
Epiglottis:
Lingual + apical laryngeal surface = non-keratinising stratified squamous epithelium
Laryngeal surface = ciliated pseudostraified columnar epithelium
Trachea
Ciliated pseudostratified columnar epithelium
Terminal bronchioles
Non-ciliated simple cuboidal epithelium
Oesophagus
Non-keratinising stratified squamous epithelium
Abrupt transition to simple columnar epithelium of stomach @ gastro-oesophageal junction or Z-line
Z-line is 3cm proximal to lower oesophageal sphincter
