Lecture 01
Scalp & Occipitofrontalis
Layers · Muscles · Nerve Supply · Blood Supply · Lymphatics
📍 Extent of the Scalp
Anteriorly
Supraorbital margins (eyebrows)
Posteriorly
Superior nuchal lines + External occipital protuberance
Laterally
Superior temporal lines → down to zygomatic arch
🗂️ Layers — S.C.A.L.P.
| Letter | Layer | Key Notes |
|---|---|---|
| S | Skin | Thick, hairy, numerous sebaceous glands |
| C | Connective Tissue (dense) | Fibrofatty; vessels held open when cut → profuse bleeding |
| A | Aponeurosis (epicranial) | Unites occipital & frontal bellies of occipitofrontalis; attached to temporal fascia at superior temporal lines |
| L | Loose Areolar Tissue | "Dangerous area" — valveless emissary veins → infection spreads intracranially; continues down to eyelids |
| P | Pericranium | Periosteum of outer skull; firmly attached at sutures |
⚠️ Clinical: Loose areolar tissue = "dangerous area" — emissary veins are valveless → scalp infection → dural venous sinuses → meningitis / cavernous sinus thrombosis.
💪 Occipitofrontalis Muscle
| Occipital Belly | Frontal Belly | |
|---|---|---|
| Origin | Highest nuchal line | Skin & superficial fascia of eyebrows |
| Insertion | Both → Epicranial aponeurosis | |
| Nerve (VII) | Posterior auricular branch | Temporal branch |
| Action | Retracts scalp | Raises eyebrows; frowning |
⚡ Nerve Supply of Scalp
| Nerve | Source | Area |
|---|---|---|
| Supratrochlear | V1 | Scalp to hairline (medial forehead) |
| Supraorbital | V1 | Scalp back to vertex |
| Zygomaticotemporal | V2 | Temple |
| Auriculotemporal | V3 | Temple skin |
| Great Auricular | C2,3 | Small area posterior to ear |
| Lesser Occipital | C2 | Lateral occipital + medial auricle |
| Greater Occipital | Post. ramus C2 | Large posterior scalp to vertex |
| Third Occipital | Post. ramus C3 | Small lower posterior scalp |
Motor: All scalp muscles = Facial nerve (VII) — temporal branch (frontal belly) + posterior auricular branch (occipital belly).
🩸 Arterial Supply
Front of Auricle (3)
Supratrochlear — ophthalmic (ICA)
Supraorbital — ophthalmic (ICA)
Superficial Temporal — terminal ECA
Supraorbital — ophthalmic (ICA)
Superficial Temporal — terminal ECA
Behind Auricle (2)
Posterior Auricular — ECA
Occipital — ECA
Occipital — ECA
🔵 Venous Drainage
- Supratrochlear + Supraorbital → Anterior Facial Vein
- Superficial Temporal + Maxillary → Retromandibular Vein
- Post. Auricular + Post. division Retromandibular → External Jugular Vein
- Occipital → Suboccipital Venous Plexus
🟢 Lymphatic Drainage
- Occipital region → Occipital nodes → Upper deep cervical
- Posterior to ear → Mastoid nodes → Upper deep cervical
- Anterior to ear / parotid → Pre-auricular & Parotid nodes
- Forehead → some to Submandibular nodes
SCALP
🗂️ Layers (S.C.A.L.P)
S — Skin (thick, hairy)
C — Connective tissue (vessels)
A — Aponeurosis
L — Loose areolar ⚠️ dangerous
P — Pericranium
💪 Occipitofrontalis
2 bellies → aponeurosis
Occipital: highest nuchal line
Frontal: eyebrow skin
Motor: VII (facial nerve)
Action: raises eyebrows
⚡ Sensory Nerves (8)
V1: supratrochlear, supraorbital
V2: zygomaticotemporal
V3: auriculotemporal
C2: great auricular, lesser occipital
C2,3: greater & third occipital
🩸 Arteries (5)
Supratrochlear (ICA)
Supraorbital (ICA)
Superficial temporal (ECA)
Posterior auricular (ECA)
Occipital (ECA)
🔵 Veins
Supra- → Anterior facial
Sup. temporal → Retromandibular
Post. auricular → Ext. jugular
Emissary veins (valveless!)
1
Layers
The scalp has 5 layers remembered by S.C.A.L.P — each letter = one layer.
2
Dangerous Area
Layer L (Loose areolar) = "Dangerous Area" — valveless emissary veins allow infection to reach dural sinuses.
الطبقة الرابعة = المنطقة الخطيرة
3
Profuse Bleeding
Scalp wounds bleed profusely — fibrous septa in layer C hold vessels open, preventing retraction.
4
Motor vs Sensory
Motor = Facial nerve (VII). Sensory = V1, V2, V3, C2, C3.
5
Occipitofrontalis
Both bellies insert into epicranial aponeurosis. Frontal belly raises eyebrows & wrinkles forehead.
6
Arteries Rule
3 in front of auricle (supratrochlear, supraorbital, sup. temporal) + 2 behind (post. auricular, occipital).
7
ICA vs ECA
Supratrochlear & supraorbital = from ICA (via ophthalmic). The other 3 scalp arteries = from ECA.
8
Retromandibular
Superficial temporal + Maxillary vein = Retromandibular vein. Posterior division + Post. auricular = External jugular.
9
Pericranium & Sutures
Pericranium is firmly attached at sutures → subperiosteal haematoma (cephalhaematoma) is limited to one bone.
10
Temple Nerve Supply
Temple is supplied by both V2 (zygomaticotemporal) and V3 (auriculotemporal).
Answered: 0/30
Correct: 0
Wrong: 0
🧩 Mnemonics for this lecture's key points.
S.C.A.L.P
Layers of the Scalp
Skin – Connective tissue (dense) – Aponeurosis – Loose areolar tissue – Pericranium.
Remember them superficial to deep; each letter is the first letter of the layer's name.
Remember them superficial to deep; each letter is the first letter of the layer's name.
Danger Layer
Why is the Loose Areolar layer dangerous?
"L for Loose = Lethal spread" — this layer allows infection to spread intracranially via emissary veins.
Nerve & Blood Supply
Occipitofrontalis
"Front is Facial-Temporal, Back is Facial-Posterior auricular" — each belly is supplied by a different branch of the facial nerve.
For arteries: "Front is Internal (from ophthalmic), Back is External (from ECA)".
For arteries: "Front is Internal (from ophthalmic), Back is External (from ECA)".
Lecture 02
Face — Muscles, Nerves & Vessels
Orbicularis Oculi · Orbicularis Oris · Buccinator · Sensory & Motor · Blood Supply · Lymphatics
📍 Extent of the Face
Superiorly
Hairline
Inferiorly
Chin
Laterally
From ear to ear
👁️ Orbicularis Oculi
| Part | Origin | Insertion | Action |
|---|---|---|---|
| Palpebral | Medial palpebral ligament | Lateral palpebral raphe | Closes eyelids gently (blinking/sleep) |
| Orbital | Nasal part of frontal bone; frontal process of maxilla; medial palpebral ligament | Forms uninterrupted ellipse around orbit | Closes eyelids forcefully (screwing up eyes) |
Nerve supply: Facial nerve VII — zygomatic & temporal branches.
👄 Orbicularis Oris
| Part | Origin | Insertion |
|---|---|---|
| Superficial | From nearby surrounding muscles | Forms an ellipse around the mouth |
| Deep | Maxilla and mandible in midline |
Nerve: Facial nerve VII — buccal & marginal mandibular branches. Action: Closes and protrudes lips (kissing, whistling).
💨 Buccinator
Origin
Maxilla & mandible above/below 3 molars + Pterygomandibular raphe
Insertion
Blends with orbicularis oris. Upper & lower fibers → opposite side. Middle fibers cross at angle of mouth.
Nerve
Facial nerve VII — buccal branch
Action
Presses cheek against teeth; compresses distended cheeks
Note: Parotid duct (Stensen's) pierces buccinator opposite the upper 2nd molar.
⚡ Nerve Supply of Face
Sensory = Trigeminal (V1,V2,V3) + Great auricular (C2,3) at angle of mandible/parotid
Motor = Facial nerve VII — ALL muscles of facial expression
Motor = Facial nerve VII — ALL muscles of facial expression
| Division | Branches to Face | Area |
|---|---|---|
| V1 | Supratrochlear, Supraorbital, Lacrimal, Infratrochlear, External nasal | Forehead, upper eyelid, nose, medial canthus |
| V2 | Infraorbital, Zygomaticofacial, Zygomaticotemporal | Lower eyelid, cheek, upper lip, side of nose |
| V3 | Auriculotemporal, Buccal (sensory), Mental | Temple, cheek skin, lower lip, chin |
| C2,3 | Great Auricular nerve | Angle of mandible + parotid surface |
🩸 Arterial Supply
- Facial artery (main): submental → inferior labial → superior labial → angular artery
- Superficial temporal artery: transverse facial branch
- Small arteries accompanying sensory nerves (supraorbital, infraorbital, mental, etc.)
🔵 Venous Drainage
- Supratrochlear + Supraorbital → Anterior Facial Vein
- Superficial Temporal + Maxillary → Retromandibular Vein
- Post. auricular + Post. division retromandibular → External Jugular
- Anterior facial + Ant. division retromandibular → Common Facial Vein → Internal Jugular
🟢 Lymphatic Drainage
- Occipital → Occipital nodes → Upper deep cervical
- Post. to ear → Mastoid nodes → Upper deep cervical
- Ant. to ear / parotid → Pre-auricular & Parotid nodes
- Forehead → some to Submandibular nodes
FACE
💪 Muscles (3 key)
Orbicularis oculi (2 parts)
Palpebral → gentle closure
Orbital → forceful closure
Orbicularis oris → lips
Buccinator → cheek
⚡ Motor (ALL = VII)
Temporal → forehead
Zygomatic → orbit
Buccal → cheek, lips
Marginal mandibular → chin
Cervical → neck
🖐️ Sensory
V1 → forehead, upper lid
V2 → cheek, lower lid
V3 → lower lip, chin
C2,3 → angle mandible
🩸 Arteries
Facial artery (MAIN)
→ submental, labial, angular
Sup. temporal → trans. facial
Branches of sensory nn.
⚠️ Danger Zone
Facial ↔ cavernous sinus
Via ophthalmic veins
Nose/lip infections = DANGER
Pterygoid plexus connection
1
Motor Rule
ALL muscles of facial expression = Facial Nerve (VII). Not trigeminal.
كل عضلات الوجه = العصب الوجهي VII
2
Sensory Rule
Face sensation = Trigeminal V1,V2,V3 EXCEPT angle of mandible/parotid = Great Auricular (C2,3).
3
Buccinator Motor
Buccinator's motor supply = Facial nerve VII (NOT V3 despite being near masticators).
Buccinator حركي = VII وليس V3
4
Orbicularis Oculi
Palpebral = gentle closure (sleep). Orbital = forceful closure (bright light / tearing).
5
Danger Triangle
Facial vein → ophthalmic veins → cavernous sinus. Infections near nose/lip → potentially fatal.
مثلث الخطر في الوجه
6
Facial Artery Path
Enters face at lower border of mandible, anterior edge of masseter → winds up to medial canthus as angular artery.
7
Parotid Duct
Stensen's duct pierces buccinator → opens opposite upper 2nd molar.
8
V2 on Face
V2 exits via infraorbital foramen → supplies lower eyelid, lateral nose, upper lip, cheek.
9
Mental Nerve
Mental nerve (V3) exits mental foramen (below 2nd premolar) → lower lip and chin.
10
Buccinator Origin
Buccinator also originates from pterygomandibular raphe, shared with superior pharyngeal constrictor.
Answered: 0/30
Correct: 0
Wrong: 0
🧩 Mnemonics for facial muscles, nerves and vessels.
Muscle Functions
Key Facial Muscles
Orbicularis Oculi = closes the eye. Orbicularis Oris = the "kissing muscle", closes the mouth. Buccinator = the "trumpeter's muscle", keeps food between the teeth while chewing.
To Zanzibar By Motor Car
5 Branches of the Facial Nerve
Temporal – Zygomatic – Buccal – Marginal mandibular – Cervical.
Danger Triangle
Danger Triangle of the Face
From the corner of the mouth to the nose: infection here can reach the cavernous sinus via the valveless angular vein.
Lecture 03
Muscles of Mastication & TMJ
Temporal Fossa · Infratemporal Fossa · Temporalis · Masseter · Pterygoids · TMJ
🏛️ Temporal Fossa
Shape
Narrow fan-shaped space on lateral surface of skull
Bones
Parietal, Frontal, Temporal, Zygomatic, Sphenoid
Upper margin
Two temporal lines
Lateral boundary
Temporal fascia
Inferior
Zygomatic arch
Contents
Temporalis + Deep temporal nerves & vessels
🏛️ Infratemporal Fossa
| Boundary | Structure |
|---|---|
| Lateral | Ramus of mandible |
| Anterior | Posterior surface of maxilla |
| Roof | Infratemporal surface of greater wing of sphenoid |
| Medial | Lateral pterygoid plate |
Contents: Masseter · Medial pterygoid · Lateral pterygoid · Maxillary artery · Pterygoid plexus of veins · Mandibular nerve (V3)
💪 Muscles of Mastication
| Muscle | Origin | Insertion | Action |
|---|---|---|---|
| Temporalis | Temporal fossa & fascia | Coronoid process (to last molar) | Elevates; posterior fibers retract mandible |
| Masseter | Inferior & deep surface of zygomatic arch | Lateral surface of ramus | Elevates mandible |
| Medial Pterygoid | Deep: medial surface of lateral pterygoid plate Superficial: tuberosity of maxilla | Medial surface of angle of mandible | Elevates + protrudes; side-to-side |
| Lateral Pterygoid | Upper: infratemporal surface of greater wing of sphenoid Lower: lateral surface of lateral pterygoid plate | Front of neck of mandible + capsule & disc of TMJ | Protrudes; opens mouth; side-to-side |
Nerve supply (ALL 4): Mandibular nerve V3. Temporalis → deep temporal; Masseter → masseteric nerve; Med. pterygoid → main trunk; Lat. pterygoid → anterior division.
🦷 TMJ — Temporomandibular Joint
Type
Synovial condyloid joint
Articular surfaces
Articular tubercle + mandibular fossa of temporal bone (above) & head of mandible (below)
Cartilage
Fibrocartilage (NOT hyaline)
Nerve supply
Auriculotemporal nerve (V3)
| Ligament | Attachments | Function |
|---|---|---|
| Lateral TM ligament | Tubercle on root of zygoma → lateral surface of neck of mandible | Limits posterior displacement; protects external auditory meatus |
| Sphenomandibular | Spine of sphenoid → lingula of mandibular foramen | Accessory ligament |
| Stylomandibular | Apex of styloid process → angle of mandible | Accessory ligament |
Articular disc: Divides TMJ into upper & lower cavities. Upper surface = concavoconvex. Lower surface = concave (fits head of mandible). Attached anteriorly to lateral pterygoid tendon.
Movements: Depression · Elevation · Protraction · Retraction · Side-to-side rotation
Movements: Depression · Elevation · Protraction · Retraction · Side-to-side rotation
Mastication & TMJ
⬆️ Elevators (Close jaw)
Temporalis → coronoid
Masseter → ramus lateral
Medial pterygoid → angle medial
⬇️ Depression (Open jaw)
Lateral pterygoid (MAIN)
→ neck of mandible + disc
Also: digastric, mylohyoid
↔️ Protraction/Side
Lateral pterygoid
Medial pterygoid
Retraction: temporalis POST
🦷 TMJ Features
Synovial condyloid
Fibrocartilage (NOT hyaline)
Articular disc divides it
Nerve: auriculotemporal V3
🔗 3 Ligaments
Lateral TM → protects EAM
Sphenomandibular
Stylomandibular
All V3 nerve supply
1
All V3
ALL 4 muscles of mastication = V3 (mandibular nerve).
كل عضلات المضغ = V3
2
Open vs Close
Opening = Lateral pterygoid (mainly). Closing = Temporalis + Masseter + Medial pterygoid.
فتح = Lateral pterygoid | إغلاق = الباقي
3
Temporalis Posterior
Posterior fibers of temporalis = unique — they retract the mandible (pull backward).
4
Med vs Lat Pterygoid
Medial = quadrangular → angle medial. Lateral = triangular → neck of mandible AND disc of TMJ.
5
TMJ Fibrocartilage
TMJ surfaces = fibrocartilage (NOT hyaline) — unlike most other synovial joints.
TMJ = fibrocartilage وليس hyaline
6
Articular Disc
Disc divides TMJ into upper (gliding/translation) and lower (hinge/rotation) compartments.
7
Lateral TM Ligament
Prevents posterior displacement of mandible → protects external auditory meatus.
8
TMJ Nerve
TMJ = auriculotemporal nerve (V3) → explains why TMJ pain can radiate to the ear.
9
Lateral Pterygoid & Disc
Lateral pterygoid = ONLY masticatory muscle attached to the articular disc of TMJ.
10
ITF Contents
Infratemporal fossa: Masseter, both pterygoids, maxillary artery, pterygoid plexus, mandibular nerve (V3).
Answered: 0/30
Correct: 0
Wrong: 0
🧩 Mnemonics for the muscles of mastication and TMJ.
MTMLP
The 4 Muscles of Mastication
Masseter, Temporalis, Medial pterygoid = elevators (close the jaw). Lateral Pterygoid = the only depressor, pulls the disc forward to open the jaw.
All four are supplied by the mandibular nerve (V3).
All four are supplied by the mandibular nerve (V3).
Upper=Glide, Lower=Rotate
The Two TMJ Compartments
Upper compartment (above the disc) = gliding/translation. Lower compartment (below the disc) = rotation, like a door hinge.
Lecture 04
Mandibular Nerve (V3)
Trunk · Anterior Division · Posterior Division · Otic Ganglion · 8 Muscles
📌 Overview of V3
Type
Mixed (sensory + motor) — ONLY mixed division of trigeminal
Exit from skull
Foramen ovale → infratemporal fossa
Divisions
Trunk → Anterior (mainly motor) → Posterior (mainly sensory)
Motor supply
8 muscles (all 1st branchial arch)
🌿 Trunk Branches (before division)
- Meningeal branch (Nervus spinosus) — re-enters skull via foramen spinosum; supplies dura of middle cranial fossa
- Nerve to medial pterygoid — motor; also sends branches via otic ganglion to tensor tympani & tensor palati
⚡ Anterior Division (mainly motor, 1 sensory exception)
| Branch | Type | Supply |
|---|---|---|
| Masseteric nerve | Motor | Masseter muscle |
| Deep temporal nerves (ant. & post.) | Motor | Temporalis muscle |
| Nerve to lateral pterygoid | Motor | Lateral pterygoid |
| Buccal nerve | Sensory only (exception!) | Skin & mucosa of cheek (NOT buccinator muscle) |
Remember: Buccal nerve = ONLY sensory branch in anterior division. Buccinator motor = Facial nerve VII.
🌿 Posterior Division (mainly sensory, 1 motor exception)
| Branch | Type | Supply |
|---|---|---|
| Auriculotemporal nerve | Sensory + parasympathetic | Temple, auricle, EAM, TMJ. Two roots encircle middle meningeal artery. Carries para (from otic ganglion) → parotid gland. |
| Lingual nerve | Sensory (+ chorda tympani) | General sensation ant. 2/3 tongue + floor of mouth. Joined by chorda tympani (VII) → taste ant. 2/3 + secretomotor to sublingual & submandibular glands. |
| Inferior alveolar nerve | Sensory + 1 motor branch | Gives nerve to mylohyoid (motor) before entering mandibular foramen. Enters mandibular canal → lower teeth. Exits as mental nerve → lower lip & chin. |
🔮 Otic Ganglion
- Location: Below foramen ovale, medial to V3
- Parasympathetic root: Lesser petrosal nerve (CN IX)
- Sympathetic root: Plexus around middle meningeal artery
- Sensory root: Auriculotemporal nerve (V3)
- Post-ganglionic: Ride auriculotemporal nerve → parotid gland (secretomotor)
💪 8 Muscles Supplied by V3
4 Muscles of Mastication
Temporalis · Masseter · Medial pterygoid · Lateral pterygoid
4 Other Muscles
Mylohyoid · Anterior belly of digastric · Tensor tympani · Tensor palati
All 8 are derived from the 1st branchial arch (mandibular arch).
V3 — Mandibular Nerve
🚪 Exit & Type
Foramen ovale
→ Infratemporal fossa
ONLY mixed nerve (V1,V2 = sensory)
🌿 Trunk Branches
Nervus spinosus (meningeal)
→ via foramen spinosum
Nerve to medial pterygoid
→ also: tensor tympani/palati
⬅️ Anterior Division
Masseteric → masseter
Deep temporal → temporalis
→ Lateral pterygoid
Buccal nerve (SENSORY only!)
➡️ Posterior Division
Auriculotemporal → parotid
Lingual + chorda tympani
Inf. alveolar → mental nerve
Nerve to mylohyoid (MOTOR)
🔮 Otic Ganglion
Para root: lesser petrosal IX
Sensory: auriculotemporal V3
Output → parotid gland
Below foramen ovale
1
Only Mixed
V3 = ONLY mixed division of trigeminal. V1 and V2 are purely sensory.
V3 فقط = حسي + حركي
2
Foramen Ovale
V3 → foramen ovale. V2 → foramen rotundum. V1 → superior orbital fissure.
3
Buccal Exception
Buccal nerve is in anterior division (mainly motor) but is itself purely sensory.
4
Chorda Tympani
Chorda tympani (VII) joins lingual nerve → taste ant. 2/3 tongue + secretomotor to sublingual & submandibular.
Chorda tympani تنضم للـ lingual
5
Nerve to Mylohyoid
Branches from inferior alveolar nerve just before it enters the mandibular foramen.
6
Auriculotemporal Roots
Two roots encircle the middle meningeal artery.
جذرين يحيطان بـ middle meningeal artery
7
8 Muscles
V3 → 8 muscles: 4 masticatory + mylohyoid + ant. digastric + tensor tympani + tensor palati. All = 1st branchial arch.
8
Otic Para Root
Otic ganglion para root = lesser petrosal (IX). Compare: PPG para root = greater petrosal (VII).
9
Nervus Spinosus
Meningeal branch of V3 enters skull via foramen spinosum with the middle meningeal artery.
10
Mental Nerve
Inferior alveolar terminates as mental nerve via mental foramen → lower lip & chin skin.
Answered: 0/30
Correct: 0
Wrong: 0
🧩 Mnemonics for the branches of the mandibular nerve (V3).
Anterior Division
Mostly Motor + 1 Sensory
Supplies the muscles of mastication (Masseteric, Deep temporal, Pterygoid nerves) + one sensory branch, the Buccal nerve.
AIL
Posterior Division = Mostly Sensory + 1 Motor
Auriculotemporal – Inferior alveolar – Lingual (all sensory, except the branch to Mylohyoid off the inferior alveolar nerve, which is motor).
Otic Ganglion
Related to V3, Not a Branch of It
Hangs off the V3 trunk; relays parasympathetic fibers (from CN IX via the lesser petrosal nerve) to the parotid gland.
Lecture 05
Maxillary Nerve (V2) & Pterygopalatine Fossa
V2 Branches · PPG Ganglion · Pterygopalatine Fossa · Maxillary Artery
📌 Overview of V2
Type
Purely sensory
Exit
Foramen rotundum → pterygopalatine fossa
Continues as
Infraorbital nerve → infraorbital foramen → face
🏛️ Pterygopalatine Fossa — Boundaries
| Wall | Structure | Communication |
|---|---|---|
| Posterior | Pterygoid process of sphenoid | Foramen rotundum → MCF; Pterygoid canal |
| Anterior | Posterior surface of maxilla | — |
| Medial | Perpendicular plate of palatine bone | Sphenopalatine foramen → nasal cavity |
| Lateral (open) | Pterygomaxillary fissure | → Infratemporal fossa |
| Superior | — | Inferior orbital fissure → orbit |
Contents: V2 (maxillary nerve) · Pterygopalatine ganglion · 3rd part of maxillary artery
🌿 Branches of V2
| Branch | Area Supplied |
|---|---|
| Meningeal branch | Dura of middle cranial fossa |
| Zygomatic nerve | Zygomaticotemporal (temple) + Zygomaticofacial (cheekbone). Also carries para to lacrimal gland via lacrimal nerve (V1). |
| PSA — Posterior superior alveolar | Upper molar teeth |
| MSA — Middle superior alveolar | Upper premolars |
| ASA — Anterior superior alveolar | Upper incisors & canine |
| Infraorbital nerve | Lower eyelid, lateral nose, upper lip, cheek |
| Greater palatine | Hard palate (posterior) |
| Lesser palatine | Soft palate |
| Nasopalatine | Anterior hard palate (behind incisors) |
| Posterior superior nasal | Nasal mucosa |
🔮 Pterygopalatine Ganglion (PPG)
- Para root: Greater superficial petrosal nerve (VII) + deep petrosal (sympath) = nerve of pterygoid canal → PPG
- Sympathetic root: Superior cervical ganglion → ICA plexus → deep petrosal nerve → nerve of pterygoid canal
- Sensory root: V2 (maxillary nerve) — passes through without synapsing
- Post-ganglionic output: V2 → zygomatic → zygomaticotemporal → lacrimal nerve (V1) → lacrimal gland (tears)
🩸 Maxillary Artery — 3 Parts × 5 Branches = 15
| Part | Relation to Lat. Pterygoid | Key Branches |
|---|---|---|
| 1st part | Medial to (before) lateral pterygoid | Deep auricular · Ant. tympanic · Middle meningeal (→ foramen spinosum) · Accessory meningeal · Inferior alveolar |
| 2nd part | Between heads of lateral pterygoid | Masseteric · Deep temporal · Buccal · Pterygoid branches |
| 3rd part | In pterygopalatine fossa | PSA · Infraorbital · Greater palatine · Pharyngeal · Sphenopalatine |
🔵 Pterygoid Venous Plexus
- Lies around lateral pterygoid muscle
- Drains → short maxillary vein → retromandibular vein
- Communicates with cavernous sinus (via emissary veins through foramen ovale/lacerum) — DANGER zone
- Also communicates with facial vein via deep facial vein
V2 — Maxillary Nerve
🚪 Exit & Type
Foramen rotundum
→ Pterygopalatine fossa
Purely SENSORY
🏛️ PPF Connections
Foramen rotundum → MCF
Sphenopalatine → nasal
Inf. orbital fissure → orbit
Pterygomaxillary → ITF
Pterygoid canal → foramen lacerum
🌿 V2 Branches
Zygomatic → temple + lacrimal
PSA/MSA/ASA → upper teeth
Infraorbital → lower lid, lip
Palatine → palate
🔮 PPG Ganglion
Para: greater petrosal VII
Symp: deep petrosal
= nerve of pterygoid canal
Output → lacrimal gland
🩸 Maxillary Artery
3 parts × 5 branches = 15
Middle meningeal → spinosum
Inf. alveolar → mandibular canal
Sphenopalatine → nasal
1
V2 Purely Sensory
V2 = purely sensory — no motor fibers at all.
V2 = حسي فقط
2
Foramen Rotundum
V2 exits via foramen rotundum into the pterygopalatine fossa.
3
PPG Para Root
PPG para root = greater superficial petrosal (VII). Otic ganglion = lesser petrosal (IX).
4
Lacrimal Gland Path
PPG → post-ganglionic → zygomatic → zygomaticotemporal → lacrimal nerve (V1) → lacrimal gland.
5
Maxillary Artery
Lateral pterygoid divides it into 3 parts, each 5 branches = 15 total.
3 أجزاء × 5 فروع = 15 فرع
6
Middle Meningeal A.
1st branch of 1st part of maxillary artery. Enters skull via foramen spinosum.
7
Open PPF Boundary
Only OPEN (lateral) side of PPF = pterygomaxillary fissure → infratemporal fossa.
8
Nerve of Pterygoid Canal
= Greater petrosal (para, VII) + deep petrosal (sympath) → enters PPG.
9
Pterygoid Venous Plexus
Pterygoid plexus → retromandibular vein. Also connects to cavernous sinus — infection danger!
10
Sphenopalatine Foramen
Connects PPF to nasal cavity — transmits nasopalatine, posterior superior nasal nerves + sphenopalatine artery.
Answered: 0/30
Correct: 0
Wrong: 0
🧩 Mnemonics for the maxillary nerve (V2) and pterygopalatine fossa.
By Location
V2 Branches Grouped by Region
Inside the skull: Meningeal. In the pterygopalatine fossa: Zygomatic + Infraorbital + ganglionic branches. In the infraorbital canal: Superior alveolar nerves. On the face: terminal branches.
Pterygopalatine Ganglion
Source of Parasympathetic Fibers
Comes from the facial nerve (Greater petrosal nerve), NOT from V2; V2 only passes through as a pathway for sensory fibers.
1-2-3
Parts of the Maxillary Artery
1st part = "bony" (near the ear/mandible). 2nd part = "muscular" (relates to Lateral pterygoid). 3rd part = "pterygopalatine" (deep branches to nose/palate).
Lecture 06
Mandible & Parotid Gland
Mandible Bony Features · Parotid Gland Overview · Parotid Duct · Nerve & Lymphatic Supply
🦴 Mandible — Bony Features
Definition
Largest & strongest bone of the face. Horseshoe-shaped body + pair of rami. Articulates with skull at TMJ.
Symphysis Menti
Line of fusion of two halves during development (midline of body)
Mental Foramen
Below 2nd premolar → transmits terminal branches of inferior alveolar nerve & vessels (mental nerve & artery)
Mental Spines
Internal surface → genioglossus (above) + geniohyoid (below)
Mylohyoid Line
Oblique ridge on internal surface → attachment of mylohyoid muscle (below 3 molars)
Sublingual Fossa
Above anterior part of mylohyoid line — lodges sublingual gland
Submandibular Fossa
Below posterior part of mylohyoid line — lodges submandibular gland
Alveolar Margin
Upper border of body → 16 sockets for tooth roots in the adult
Digastric Fossa
Lower border of body → origin of anterior belly of digastric
Ramus — External
Coronoid process (anterior) + Condyloid process/head (posterior), separated by mandibular notch. Oblique line → buccinator attachment.
Mandibular Foramen
Internal surface of ramus → inferior alveolar nerve & vessels enter here. Lingula in front → attachment of sphenomandibular ligament.
Muscles attached: Buccinator · Masseter · Medial pterygoid · Temporalis · Lateral pterygoid · Mylohyoid · Genioglossus · Geniohyoid · Anterior belly of digastric
Nerves related: Lingual · Inferior alveolar · Mental · Mylohyoid nerve · Auriculotemporal · Nerve to masseter | Arteries related: Facial · Inferior alveolar · Mental · Artery to mylohyoid · External carotid · Maxillary · Masseteric
🦷 Parotid Gland — Full Overview
Type & Composition
Largest salivary gland. Composed mostly of serous acini.
Site
Below external auditory meatus · Behind ramus of mandible · In front of sternocleidomastoid
Lobes
Facial nerve divides it: Superficial lobe (80%) — on posterior masseter. Deep lobe (20%) — extends medially through stylomandibular tunnel.
Stylomandibular Tunnel
Anteriorly: posterior edge of ramus. Posteriorly: anterior border of SCM + posterior digastric. Deeply: stylomandibular ligament.
Contents (deep→superficial)
1. External carotid artery (deepest) 2. Retromandibular vein (middle) 3. Facial nerve (superficial)
Parotid Duct (Stensen's)
Superficial to masseter. Middle third of EAM → midpoint upper lip. Inferior to transverse facial artery. Turns medially → pierces buccinator → opens opposite upper 2nd molar.
Sensory Nerve Supply
Great auricular (C2,3) → capsule | Auriculotemporal (V3) → parenchyma
Parasympathetic Supply
CN IX → tympanic branch → tympanic plexus → lesser petrosal → otic ganglion → post-ganglionic via auriculotemporal → parotid gland (secretomotor)
Sympathetic Supply
Superior cervical ganglion → fibers pass along arteries to gland
Lymphatics
Parotid LN (within) → parotid gland, nasopharynx, palate, middle ear, EAM. Preauricular LN → temporal region, scalp, upper face. Both → superficial & deep cervical nodes.
Mandible & Parotid
🦴 Mandible Landmarks
Mental foramen (below P2)
Mandibular foramen + lingula
Mylohyoid line
Sublingual vs submandibular fossa
🦷 Parotid Lobes
Superficial 80% (over masseter)
Deep 20% (stylomandibular tunnel)
Divided by facial nerve
🧪 Contents (deep→superficial)
1. External carotid artery
2. Retromandibular vein
3. Facial nerve VII
🚰 Parotid Duct
Superficial to masseter
Pierces buccinator
Opens opposite upper 2nd molar
🧠 Nerve Supply
Sensory: great auricular + auriculotemporal
Para (secretomotor): IX → otic ganglion → auriculotemporal
Sympathetic: superior cervical ganglion
1
Mandibular Foramen
Mandibular foramen on internal surface of ramus → entry point for inferior alveolar nerve & vessels. Lingula guards it anteriorly.
2
Mental Foramen Location
Mental foramen lies below the 2nd premolar — transmits mental nerve & artery (terminal branches of inferior alveolar).
3
Sublingual vs Submandibular Fossa
Above mylohyoid line = sublingual fossa (sublingual gland). Below = submandibular fossa (submandibular gland).
فوق الخط = تحت اللسان | تحت الخط = تحت الفك
4
Parotid Lobe Split
The facial nerve is the structure that divides the parotid gland into superficial (80%) and deep (20%) lobes.
5
Contents Order
Inside the parotid, from deep to superficial: artery → vein → nerve (External carotid → Retromandibular vein → Facial nerve).
6
Stensen's Duct Path
Parotid duct pierces buccinator, opening into the mouth opposite the upper 2nd molar.
7
Secretomotor Pathway
Parasympathetic to parotid: CN IX → tympanic branch → lesser petrosal → otic ganglion → auriculotemporal nerve → gland.
8
Sensory Split
Capsule = great auricular nerve (C2,3). Parenchyma (gland substance) = auriculotemporal nerve (V3).
9
Stylomandibular Tunnel
Deep lobe of parotid passes through this tunnel, bounded deeply by the stylomandibular ligament.
10
Mandible Muscle Attachments
Mandible gives attachment to all 4 muscles of mastication plus buccinator, mylohyoid, genioglossus, geniohyoid, and anterior digastric.
Answered: 0/30
Correct: 0
Wrong: 0
🧩 Mnemonics for the mandible and parotid gland.
Bony Landmarks
Mandible Landmarks
Mental foramen below the 2nd premolar. Mandibular foramen at the Lingula. Coronoid process = attachment for Temporalis. Condylar process = forms the TMJ.
7 on top, vein below
Order of Structures Inside the Parotid Gland
Superficial to deep: Facial nerve (VII) first, then the Retromandibular vein, and deepest is the External carotid artery (ECA).
Lecture 07
Cervical Fascia & Posterior Triangle
Cervical Fascia Layers · SCM · Platysma · Posterior Triangle Boundaries & Contents · Cervical Plexus · Spinal Accessory Nerve
🦴 The Neck
Extent
Lower margin of mandible → upper border of clavicle
Skeleton
Cervical vertebrae — convex forward, supports skull
Cross-section
Behind: extensor muscles · Front: flexors · Central: viscera · Sides: neurovascular
Division
SCM divides neck → Anterior + Posterior triangles
🔶 Cervical Fascia — 4 Layers
| Layer | Description | Key Relations |
|---|---|---|
| Investing (Deep) | Thick, encircles entire neck | Splits for SCM & trapezius · Roof of posterior triangle |
| Prevertebral | Surrounds vertebral column + attached muscles | Scalenes, deep back muscles · Floor of posterior triangle |
| Pretracheal | Surrounds trachea, esophagus, thyroid | Superiorly → hyoid · Inferiorly → fibrous pericardium |
| Carotid Sheath | Neurovascular compartment | CCA/ICA, IJV, vagus · Ansa cervicalis anterior · Sympathetic chain posterior |
Fascial spaces (pretracheal + retropharyngeal) allow infection to spread from neck → thoracic mediastinum
💪 Platysma Muscle
Origin
Deep fascia over chest
Insertion
Body of mandible + angle of mouth
Nerve
Cervical branch of facial nerve (VII)
Action
Depresses mandible and angle of mouth
💪 Sternocleidomastoid (SCM)
Sternal Head
Anterior surface of manubrium (upper part)
Clavicular Head
Superior surface of medial 1/3 of clavicle
Insertion
Lateral surface of mastoid process + lateral half of superior nuchal line
Nerve
Spinal Accessory Nerve (CN XI)
- One side: Tilts head to same side + turns face to opposite side
- Both sides: Draw head forwards
🔷 Posterior Triangle — Boundaries
Anteriorly
Posterior edge of SCM
Posteriorly
Anterior edge of trapezius
Base
Middle 1/3 of clavicle
Apex
Occipital bone posterior to mastoid process
Roof
Investing layer of deep cervical fascia
Floor
Prevertebral fascia → splenius capitis, levator scapulae, 3 scalenes
Divided by inferior belly of omohyoid: Occipital triangle (upper, larger) + Subclavian triangle (lower, smaller)
📦 Posterior Triangle — Contents
Muscles
Inferior belly of omohyoid
Vessels
Subclavian artery & branches · Subclavian vein & tributaries · External jugular vein
Nerves
Brachial plexus · Cervical plexus · Spinal accessory (XI)
🩸 External Jugular Vein
Formation
Posterior division of retromandibular + posterior auricular vein (near angle of mandible)
Course
Superficial fascia, crosses SCM
Termination
Pierces deep fascia → subclavian vein
Tributaries
Transverse cervical, suprascapular, anterior jugular veins
⚡ Cervical Plexus (C1–C4)
| Type | Branch | Supply |
|---|---|---|
| Muscular (Deep) | Phrenic nerve (C3,4,5) | Diaphragm |
| Prevertebral + lateral vertebral muscles | Neck muscles | |
| Infrahyoid + geniohyoid (ansa cervicalis) | Hyoid muscles | |
| Cutaneous (Superficial) | Lesser occipital | Scalp behind ear |
| Great auricular | Parotid + auricle skin | |
| Transverse cervical | Anterior neck skin | |
| Supraclavicular | Shoulder + clavicle skin |
⚡ Spinal Accessory Nerve (CN XI)
- Exits cranial cavity through jugular foramen
- Descends backwards through the neck
- Passes through SCM (which it supplies)
- Crosses posterior triangle within investing layer of deep cervical fascia
- Supplies both SCM and trapezius
NECK — Fascia & Posterior Triangle
🔶 4 Fascial Layers
Investing → encircles neck, splits for SCM + trapezius
Prevertebral → vertebral column + scalenes
Pretracheal → trachea/esophagus/thyroid → pericardium
Carotid sheath → CCA, IJV, vagus
💪 SCM Muscle
Origin: manubrium + medial clavicle
Insertion: mastoid + nuchal line
Nerve: CN XI (spinal accessory)
1 side: tilt + turn opposite · Both: flex head
🔷 Post. Triangle Borders
Ant: SCM · Post: trapezius
Base: clavicle · Apex: occipital bone
Roof: investing fascia
Floor: prevertebral fascia
📦 Post. Triangle Contents
Inf. belly omohyoid
Subclavian a/v · EJV
Brachial plexus · Cervical plexus · CN XI
⚡ Cervical Plexus C1–4
Deep: phrenic → diaphragm
Lesser occipital · Great auricular
Transverse cervical · Supraclavicular
1
4 Fascial Layers
Investing · Prevertebral · Pretracheal · Carotid sheath. Investing encircles whole neck and splits for SCM + trapezius.
4 طبقات لفافة الرقبة
2
Carotid Sheath Contents
CCA/ICA · IJV · Vagus (X). Ansa cervicalis = anterior; Sympathetic chain = posterior to sheath.
3
SCM Nerve = CN XI
SCM + trapezius = Spinal Accessory XI. Damage → torticollis — cannot turn head to opposite side.
SCM = العصب الإضافي الشوكي XI
4
Post. Triangle Floor
Floor = prevertebral fascia covering splenius capitis, levator scapulae, anterior/middle/posterior scalenes.
5
Platysma Nerve
Platysma = cervical branch of VII. Despite being in the neck, it is a muscle of facial expression.
Platysma = الفرع العنقي للعصب الوجهي VII
6
Fascial Space Danger
Pretracheal + retropharyngeal spaces → infection can track into thoracic mediastinum.
7
EJV Formation
EJV = posterior division of retromandibular + posterior auricular. Terminates in subclavian vein.
8
Phrenic Nerve (C3,4,5)
Deep branch of cervical plexus → diaphragm. "C3,4,5 keeps the diaphragm alive."
العصب الحجابي C3,4,5 → الحجاب الحاجز
9
Pretracheal Fascia
Superiorly → hyoid. Inferiorly → fibrous pericardium. Posterior to infrahyoid muscles.
10
CN XI in Post. Triangle
Crosses posterior triangle within the investing layer (NOT under prevertebral). Surgically vulnerable.
Answered: 0/30
Correct: 0
Wrong: 0
🧩 Mnemonics for cervical fascia and the posterior triangle.
3 Layers
Deep Cervical Fascia
Investing layer = wraps the whole neck like a "collar". Pretracheal layer = wraps only the anterior visceral structures (thyroid, trachea, esophagus). Prevertebral layer = wraps the vertebral column and its muscles.
Boundaries
Posterior Triangle Boundaries
Anterior: SCM. Posterior: Trapezius. Base: middle 1/3 of the clavicle. Apex: occipital bone.
Erb's Point
Contents of the Posterior Triangle
The Spinal accessory nerve crosses superficially. Branches of the cervical plexus (Lesser occipital, Great auricular, Transverse cervical, Supraclavicular) emerge from behind the SCM at Erb's point.
Lecture 08
Anterior Triangle
Suprahyoid & Infrahyoid Muscles · External Carotid Artery · Internal Jugular Vein · Submandibular Gland · Tongue
💪 Suprahyoid Muscles
| Muscle | Origin | Insertion | Nerve | Action |
|---|---|---|---|---|
| Mylohyoid | Mylohyoid line of mandible | Hyoid + median raphé | Nerve to mylohyoid (V3) | Supports floor of mouth; elevates hyoid |
| Digastric Ant. | Digastric fossa of mandible | Intermediate tendon → hyoid | Nerve to mylohyoid (V3) | Opens mouth (hyoid fixed); raises hyoid (mandible fixed) |
| Digastric Post. | Mastoid notch | Intermediate tendon → hyoid | Facial nerve (VII) | Same as above |
| Stylohyoid | Base of styloid process | Lateral body of hyoid | Facial nerve (VII) | Pulls hyoid posterosuperiorly (swallowing) |
| Geniohyoid | Inferior mental spine of mandible | Body of hyoid | C1 via hypoglossal XII | Raises hyoid; pulls mandible down (hyoid fixed) |
💪 Infrahyoid Muscles (Strap Muscles)
| Muscle | Origin | Insertion | Nerve | Action |
|---|---|---|---|---|
| Sternohyoid | Back of sternoclavicular joint + manubrium | Body of hyoid | Ansa cervicalis (C1,2,3) | Depresses hyoid |
| Omohyoid | Inf. belly: superior border of scapula | Via fascial sling to clavicle | Ansa cervicalis (C1,2,3) | Depresses hyoid |
| Sternothyroid | Posterior surface of manubrium sterni | Oblique line of thyroid cartilage | Ansa cervicalis (C1,2,3) | Depresses thyroid cartilage |
| Thyrohyoid | Oblique line of thyroid cartilage | Greater horn + body of hyoid | C1 via hypoglossal | Depresses hyoid |
Exception: Thyrohyoid is the ONLY infrahyoid muscle NOT supplied by ansa cervicalis — it is supplied by C1 via hypoglossal nerve
🫁 Submandibular Gland
Location
Under lower border of body of mandible
Parts
Superficial + deep parts divided by mylohyoid muscle
Wharton's Duct
From anterior end of deep part → under mucous membrane → opens at papilla beside frenulum of tongue
Para. Supply
VII → chorda tympani → lingual nerve → submandibular ganglion → gland
🩸 External Carotid Artery (ECA)
Origin
Terminal branch of CCA at C4
Course
Carotid triangle → under post. belly digastric → enters parotid gland (deepest structure)
Termination
Neck of mandible → superficial temporal + maxillary
Branches
3 anterior · 2 posterior · 1 medial · 2 terminal
| Branch | Group | Supplies |
|---|---|---|
| Superior thyroid | Anterior | Thyroid gland |
| Lingual | Anterior | Tongue |
| Facial | Anterior | Face (eye to jaw) |
| Occipital | Posterior (below digastric) | Back of head |
| Posterior auricular | Posterior (above digastric) | Auricle + scalp behind ear |
| Ascending pharyngeal | Medial (small) | Pharyngeal muscles + tonsils |
| Superficial temporal | Terminal | Scalp + temple |
| Maxillary | Terminal | Meninges, ear, mandible, mastication, nasal cavity |
🩸 Internal Jugular Vein (IJV)
Origin
Continuation of sigmoid sinus — exits skull via jugular foramen
Position
Large vein deep to SCM · Lateral side of carotid sheath
Termination
Joins subclavian vein → brachiocephalic vein
Drains
Brain, face, and neck
- Tributaries: Inferior petrosal sinus · Common facial · Pharyngeal · Lingual · Superior thyroid · Middle thyroid veins
👅 Tongue
Structure
Striated muscle + mucous membrane · Divided by median fibrous septum
Intrinsic Muscles
Longitudinal, transverse, vertical · CN XII · Alter shape
Extrinsic Muscles
Genioglossus, hyoglossus, styloglossus (XII) · Palatoglossus (vagus X) · Move tongue
Arterial Supply
Lingual artery · Tonsillar branch of facial · Ascending pharyngeal
| Region | General Sensation | Taste |
|---|---|---|
| Anterior 2/3 | Lingual nerve (V3) | Chorda tympani (VII) via lingual nerve |
| Posterior 1/3 | Glossopharyngeal (IX) | Glossopharyngeal (IX) |
Lymph: Tip → submental · Sides ant. 2/3 → submandibular + deep cervical · Post. 1/3 → deep cervical only
ANTERIOR TRIANGLE
💪 Suprahyoid (5)
Mylohyoid → V3
Digastric ant. → V3
Digastric post. → VII
Stylohyoid → VII
Geniohyoid → C1 via XII
💪 Infrahyoid (4)
Sternohyoid → ansa C1,2,3
Omohyoid → ansa C1,2,3
Sternothyroid → ansa C1,2,3
Thyrohyoid → C1 only (exception!)
🩸 ECA Branches
Ant: sup. thyroid, lingual, facial
Post: occipital, post. auricular
Medial: ascending pharyngeal
Terminal: sup. temporal + maxillary
👅 Tongue Nerves
Motor ALL = XII (except palatoglossus = X)
Ant 2/3 sensation = lingual V3
Ant 2/3 taste = chorda tympani VII
Post 1/3 both = CN IX
🩸 IJV
Origin: sigmoid sinus → jugular foramen
Lateral in carotid sheath
Ends: subclavian → brachiocephalic
Tributaries: inf. petrosal, facial, lingual, thyroid
1
Digastric Dual Nerve
Ant. belly = V3 (nerve to mylohyoid). Post. belly = VII (facial). Two bellies, two different nerves!
Digastric = بطنين بعصبين مختلفين
2
Thyrohyoid Exception
Only infrahyoid NOT by ansa cervicalis — supplied by C1 via hypoglossal nerve. All others = ansa C1,2,3.
3
ICA Has NO Neck Branches
ICA gives no branches in the neck. ECA gives all its named branches in the neck.
ICA ليس له فروع في الرقبة
4
Tongue Motor = XII
All tongue muscles = CN XII EXCEPT palatoglossus = vagus (X).
كل عضلات اللسان = XII ما عدا palatoglossus = X
5
Tongue Sensation vs Taste
Ant 2/3 sensation = lingual (V3). Ant 2/3 taste = chorda tympani (VII). Post 1/3 = CN IX for both.
6
IJV Origin
IJV = continuation of sigmoid sinus → exits jugular foramen → joins subclavian → brachiocephalic vein.
7
Wharton's Duct
Submandibular duct opens beside frenulum of tongue. Para = chorda tympani (VII) → submandibular ganglion.
8
ECA Terminal Branches
ECA terminates at neck of mandible → superficial temporal (scalp) + maxillary (deep face).
9
Geniohyoid Nerve = C1
Geniohyoid = suprahyoid muscle but nerve is C1 via hypoglossal, NOT V3. Often confused!
Geniohyoid = C1 عبر العصب تحت اللساني
10
Tongue Lymph
Tip → submental. Sides ant. 2/3 → submandibular + deep cervical. Post. 1/3 → deep cervical only.
Answered: 0/30
Correct: 0
Wrong: 0
🧩 Mnemonics for the anterior triangle.
Above the Hyoid
Suprahyoid Muscles (4)
Digastric – Stylohyoid – Mylohyoid – Geniohyoid: elevate the hyoid bone and floor of the mouth.
Below the Hyoid
Infrahyoid "Strap" Muscles (4)
Superficial layer: Sternohyoid + Omohyoid. Deep layer: Sternothyroid + Thyrohyoid. Function: depress the hyoid bone.
The Lingual Nerve "Bridge"
Submandibular Gland & Wharton's Duct
The lingual nerve loops around Wharton's duct like a "bridge" — crossing it from lateral to medial twice along its course.