Laboratory Identifications and Relations -- Skull


[ SBMP ] [ Skull ] [ Face ] [ Cavernous Sinus ] [ Orbit ] [ Parotid Region, TMJ, Mandible ] [ Infratemporal Fossa ] [ Pterygopalatine Fossa ]

Skull - Anterior View

  1. supraorbital notch (foramen) - communication between orbit and face
  2. glabella - between supercilliary ridges
  3. supercilliary ridge - anterior boundary of potential space of scalp
  4. superior orbital fissure - greater and lesser wings of sphenoid bone, communication between middle cranial fossa and orbit
  5. inferior orbital fissure - greater wing sphenoid and maxilla, communication between pterygopalatine fossa, infratemporal fossa, and orbit
  6. foramina for anterior and posterior ethmoidal nn. - communication between orbit, ethmoid air cells, and lateral nasal cavity
  7. foramina for zygomaticotemporal and zygomaticofacial nerves - communication between orbit and face
  8. lacrimal fossa - location of lacrimal sac
  9. tubercle for medial palprebral lig. - anterior to lacrimal fossa
  10. infraorbital groove, canal, and foramen - communication between orbit and face
  11. perpendicular plate ethmoid bone - superior bony contribution to nasal septum
  12. vomer - inferior bony contribution to nasal septum
  13. superior, middle, and inferior nasal conchae - lateral nasal wall (called turbinates when covered with mucosa as in life)
  14. superior alveolar process

Skull - Lateral View

  1. pterion - opposite anterior branch middle meningeal a. (epidural hematoma), suture site of four bones
  2. external auditory meatus
  3. zygoma
  4. temporal process - this plus zygoma constitutes the zygomatic arch, site of origin for masseter
  5. mastoid process - origin of sternocleidomastoid, common bony landmark
  6. styloid process - three muscles having three different innervations take origin here (the non-"inverted tripod" of the head)
  7. coronal and lambdoid sutures - frontal to parietal to occipital
  8. posterior aspect of maxilla
  9. foramen for posterior superior alveolar n. - between infratemporal fossa and maxillary sinus
  10. lateral pterygoid plate
  11. pterygomaxillary fissure - between pterygopalatine fossa and infratemporal fossa
  12. mandibular fossa - temporomandibular joint
  13. articular tubercle - temporomandibular joint

Skull - Base View

  1. incisive foramen - communication between nasal cavity and oral cavity nasopalatine nn.
  2. greater palatine foramen and canal - communication between pterygopalatine fossa (PTF) and hard palate (oral cavity)
  3. lesser palatine foramen and canal - communication between PTF and soft palate (oral cavity)
  4. hamulus of medial pterygoid plate - sphenoid bone, tenser veli palatini
  5. lateral pterygoid plate - origin of lateral and medial pterygoid mm., medial border infratemporal fossa
  6. scaphoid fossa - base of pterygoid plates, origin of tenser veli palatini
  7. lacerate foramen - filled by cartilage in life, emissary v., opening of pterygoid canal, opening of carotid canal, posterior border cavernous sinus
  8. pterygoid canal - communication between middle cranial fossa and pterygopalatine fossa, vidian n., deep petrosal n., greater superficial petrosal n.
  9. pharyngeal canal - communication between nasopharynx and pterygopalatine fossa, pharyngeal n., (palatovaginal canal)
  10. carotid canal - communication between base of skull and middle cranial fossa, internal carotid a.
  11. foramen ovale - communication between infratemporal fossa and middle cranial fossa
  12. foramen spinosum - communication between middle cranial fossa and infratemporal fossa, middle meningeal a.
  13. spine of sphenoid bone - adjacent to foramen spinosum, sphenomandibular ligament
  14. stylomastoid foramen - communication between posterior cranial fossa and parotid region via facial canal
  15. jugular foramen and fossa - communication between posterior cranial fossa and base of skull, int. jugular v., inf. petrosal v, IX, X, XI
  16. tympanic canaliculus - between base of skull and middle ear, recurrent (tympanic br.) of IX
  17. petrotympanic fissure - between middle ear and infratemporal fossa, chorda tympani
  18. pharyngeal tubercle - buccopharyngeal fascia
  19. occipital condyle - atlantooccipital joint, flexion, extension
  20. external occipital protuberance - common landmark, superior nuchal line
  21. foramen magnum - not to be overlooked

Mandible

  1. condyle - site of insertion for inferior head lateral pterygoid muscle
  2. neck - anterior to external auditory canal
  3. coronoid process - insertion of temporalis muscle
  4. mandibular notch - transmits masseteric artery and nerve to masseter muscle
  5. ramus - lateral boarder of infratemporal fossa, retromandibular vein, maxillary artery, parotid gland
  6. angle - near level of lingula (medial surface)
  7. body - most commonly broken bone in males, fracture puts inferior alveolar nerve and artery at risk
  8. inferior alveolar process - base of teeth
  9. mandibular foramen - transmits inferior alveolar nerve and artery into mandible, inferior to lingula
  10. lingula - site of attachment of sphenomandibular ligament
  11. digastric fossa - origin of anterior belly of digastric muscle
  12. superior and inferior mental spine - origin of genioglossus and geniohyoid muscles
  13. sphenomandibular ligament - from spine of sphenoid to lingula, limits depression of the mandible
  14. mental foramen - transmits mental nerve and artery (continuation of inferior alveolar nerve)
  15. inferior alveolar nerve and artery - provides the inferior dental plexus
  16. inferior dental plexus
  17. temporalis muscle - arises from temporal fossa, medial to zygomatic arch, inserts on coronoid process and anterior ramus
  18. masseter muscle - arises from zygomatic arch, inserts on lateral body and angle of mandible
  19. medial pterygoid muscle - originates from medial aspect of lateral pterygoid plate, inserts on medial body
  20. mental nerve and artery

Pterygopalatine Fossa (PTF) and Communcations

  1. foramen rotundum - bony communication between PTF and middle cranial fossa, posterosuperior wall of PTF
  2. pterygoid canal - bony communication between PTF and middle cranial fossa, anterior lip of lacerate foramen, posterior wall of PTF
  3. pharyngeal (palatovaginal) canal - bony communication between PTF and nasopharynx, posteroinferior wall of PTF
  4. lesser palatine canal - bony communication between PTF and oral cavity (soft palate), floor (inferior wall) of PTF
  5. greater palatine canal - bony communication between PTF and oral cavity (hard palate), floor (inferior wall) of PTF
  6. sphenopalatine canal - bony communication between PTF and nasal cavity, medial wall of PTF
  7. pterygomaxillary fissure - bony communication between PTF and infratemporal fossa, lateral wall of PTF
  8. inferior orbital fissure - bony communication between PTF and orbit, anterior wall of PTF

Cranial Nerve Foramina

  1. cribriform plate of ethmoid bone - transmits olfactory fila between anterior cranial fossa and nasal cavity
  2. optic canal - transmits optic nerve  from middle cranial fossa to orbit
  3. superior orbital fissure - transmits oculomotor, trochlear, ophthalmic (trigeminal), and aducens nerves from middle cranial fossa to orbit
  4. internal auditory meatus - transmits facial and vestibulocochlear nerves from posterior cranial fossa into the petris temporal bone
  5. jugular foramen - transmits glossopharyngeal, vagus, and spinal accessory nerves from the posterior cranial fossa to the base of skull region
  6. hypoglossal canal - transmits hypoglossal nerve from the posterior cranial fossa to the base of skull region

The Structural Basis of Medical Practice
(Copyright Protected -- L.A. Evey, Ph.D.)