Lecture 11: Infratemporal Flashcards
Where is the infratemporal fossa and what are the boundaries?
It is a 3D space
The roof is formed by the squamous part of the temporal bone and the sphenoid bone. The lateral plate of the sphenid bone forms the medial boundary. The maxillary bone forms the anterior boarder. The lateral side there is the ramus of the mandible.
What is the TMJ and what is its clinical relevance?
The temporalmandibular joint is an atypical synovial joint with fibrocartilage (with articular disc dividing into upper and lower joint cavity). It is a major cause of head and neck pain. It is formed by the condylar part of the mandible and the mandibular fossa of the temporal bone.
It has a lateral ligament of the capsule stabilising and also has two extracapsular ligamnets: sphenomandibular and stylomandibular ligament.
The lateral pterygoid muscles directly attach to the TMJ
Movement of the TMJ? (not too essential to learn)
Muscles of mastication?
- Temporalis muscle (from temporal bone to coronoid process
- Masseter muscle (attaches to angle to mandible to zygomatic arch and maxillary process of this arch)
- Lateral pterygoid (lateral side of lateral pterygoid plate)
- medial pterygoid (medial side of the lateral pterygoid plate)
Only the lateral and medial pterygoid muscles are inside the infratemporal fossa along with the sphenomandibular ligament
Maxillary arteries in the infratemporal fossa?
The maxillary artery enters this area and gives off the important branches of the MMA and the Inf Alverolar artery.
The other arteries are not important for us
Neural structures in the infratemporal fossa?
CN V3 has both motor and sensory through the foramen ovale giving off lots of branches via ant and post trunk.
Anterior trunk: muscle of mastication innervation and bucccal n. (sensory for the face - lower half of the cheek)
Posterior trunk: lingual nerve (sensation to floor of mouth and runs with chorda tympani), inferior alveolar and auriculotemporal nerve-(also has the lesser petrosal nerve CN IX that runs with it to supply PS innervation to the parotid)
Venous plexus?
The pterygoid plexus forms from the maxillary vein and infra-orbital vein and inferior alveolar vein
Has emissary veins going back to the cavernous sinus
Where is the pterygopalatine fossa? boarders?
You first must cut the zygomatic arch to be able to see it.
anteriorally = maxilla
Roof = sphenoid bone (+carotid canal and therefore, ICA)
medial boarder = palatine bone
posteriorally = pterygoid plate and sphenoid bone
What enters and runs through the pterygopalatine fossa?
Sphenopalatine artery from the maxillary runs through the sphenopalatine foramen to the nasal cavity and can cause posterior epistaxis
CN V2 runs through the foramen rotundum into the pterygopalatine fossa to supply sensory info
‘there are others as well but not necessary to know’
Contents of the pterygopalatine fossa?
Maxillary artery - has 15 branches in total
- sphenopalatine artery is the most important to us
- also superior alveolar, zygomatic and infraoribtal but not necessary for us.
Neural structures - Pterygopalatine ganglion= Hay fever ganglion
- hay fever ganglion can be destroyed to stop hay fever
- greater petrosal (VII) : para-sympathetic - enters ganglion and goes to lacrimal glands and nasal cavity
- Deep petrosal nerve (superior cervical ganglion with internal carotid): sympathetic - enters ganglion and then goes to V2 area
Venous structures?
Pterygoid plexus
