Question

9-12 only

9. What are the cu t s UI ULTIMIT 10. What is the name of the condition when an car infection spreads to the bone behind the car? What is the risk? 11. As mentioned before, know the structures that go through the different holes (foramen) etc that were mentioned you should know in lecture notes 12. What structures go through the foramen magnum? 13. What structure attaches to the external occipital protuberance? Where else does it connect? 14. Describe the structures that form the atlanto-occipital and atlanto-axial joint. What motion do they allow? 1 know what Turk's Saddle or Sella turcica is. What are the components? What is the purpose of this structure?

Answer 1

9. Components of TMJ

The main components of TMJ are

• Joint capsule
• Articular disc
• Mandibular condyles
• Articular surface of the temporal bone
• Temporomandibular ligament
• Stylomandibular ligament
• Sphenomandibular ligament
• Lateral pterygoid muscle

10. Mastoditis is the condition when an ear infection spreads to the bone behind the ear. It is a bacterial infection of the mastoid cells in the mastoid bone.

Risk - If left untreated, mastoiditis can cause serious, even life-threatening health complications such as

• Hearing loss
• Blood clot
• Meningitis
• Brain abscess

11. Foramen has three different sections

a) Anterior Fossa b) Middle Fossa c) Posterior Fossa

a) Anterior Fossa- Composed of 3 specific bones : Frontal, Ethmoid and Lesser wings of Sphenoid.Together these bones comprise the shallowest recess of the cranium.

b) Middle Fossa - Composed of 3 specific bones : The Sphenoid and Paired Temporol bones. It is home to neurovascular structures like (Optic canal, Foramen rotundum,Foramen ovale, Foramen lacerum, Foramen spinosum) which are important for supplying sensory innervation of face, the sense of vision and blood to the cranium.

c) Posterior Fossa - Composed of 3 specific bones : The Paired Temporal bones and the Occipital bone. It is the deepest of the fossae and responsible for several passages that contain neurovascular bundles in each region of the fossa.

The Temporal portion have structures like Internal acoustic meatus, Vestibulocochlear nerve, Vestibular ganglion and Labyrinthine artery.

The Occipital portion contains structures like Jugular foramen, Hypoglossal canal and Foramen magnum.

12. Foramen Magnum - Largest of the Cranial foramen.Contains following structures

• Medulla
• Paired vertebral arteries
• Paired anterior spinal arteries
• Paired posterior spinal arteries
• Ascending portion of CN XI
• Dural veins