The temporal fossa represents the wide area of the lateral skull above the zygomatic arch. The superior and posterior margins of the fossa are formed by the superior temporal line. Inferiorly, the temporal fossa is bordered by the zygomatic arch and the infratemporal crest of the greater wing of the sphenoid bone.
Which structure is the anterior boundary of the temporal fossa?
The bony part of the temporal fossa is formed anteriorly by the zygomatic bone, somewhat more posteriorly by the greater wing of the sphenoid, and still farther posteriorly by the temporal squama.
Which type of skull has 2 temporal Fossae on either side of it?
In diapsid skull of reptiles, the two temporal fossae are separated by these bones to form the upper temporal bar.
What attaches to temporal fossa?
Temporalis MuscleThe temporalis muscle attaches above to the bone and fascia in the temporal fossa, superior to the zygomatic arch, and below to the coronoid process of the mandible and along the mandibular ramus (Figure 6-17).
What are the two fossae of the temporal?
Anterior: Posterior surface of the frontal process of the zygomatic bone and the posterior surface of the zygomatic process of the frontal bone. Inferior: Zygomatic arch laterally and by the infratemporal crest of the greater wing of the sphenoid medially.
Which of the following does not have temporal Fenestra in the skull?
Anapsids lack temporal fenestrae. Diapsids have two fenestrae on each side and evolved from ancestors that had none.
What structure marks the boundary between the temporal and infratemporal fossa?
Bony framework Bones that contribute significantly to the boundaries of the temporal and infratemporal fossae include the temporal, zygomatic, and sphenoid bones, and the maxilla and mandible. Parts of the frontal and parietal bones are also involved.
Which muscle originates on the temporal fossa?
The temporalis muscleThe temporalis muscle originates from the floor of the temporal fossa and inserts onto the coronoid process of the mandible.
What is the origin and insertion of the temporalis?
Attachments of Temporalis Muscle: Origin & Insertion Origin: (proximal attachments): Temporal lines, temporal fossa, and temporal fascia. Insertion: (distal attachments): Tip and medial surface of coronoid process of mandible.
What are the 3 cranial fossae and the bones that form the floor of each?
The bones of the anterior cranial fossa floor are the: frontal and ethmoid bones. The bones of the middle cranial fossa floor are the: temporal and sphenoid bones. The bones of the posterior cranial fossa floor is the: occipital bone.
Is temporal bone in middle cranial fossa?
The middle cranial fossa is bounded anteriorly by the sphenoid ridge, medially by the lateral wall of the cavernous sinus and Meckel's cave, posteriorly by the sphenoid wing and petrous bone, and laterally by the greater wing of sphenoid and squamous temporal bone.
What sits in the middle cranial fossae?
The middle cranial fossa is a butterfly-shaped depression of the skull base, which is narrow in the middle and wider laterally. It houses the temporal lobes of the cerebrum.
How many Fossas are in skull?
There are three distinct cranial fossae: Anterior cranial fossa (fossa cranii anterior), housing the projecting frontal lobes of the brain. Middle cranial fossa (fossa cranii media), separated from the posterior fossa by the clivus and the petrous crest housing the temporal lobe.
Which bone is the middle cranial fossa?
The superior orbital fissure which is bounded by the greater and lesser wings of the sphenoid bone contains the trochlear nerve, abducens nerve, oculomotor nerve and ophthalmic nerve. The sella turcica is a depression in the sphenoid bone. In the center of the middle cranial fossa it forms the pituitary fossa in which the pituitary gland sits.
How many regions are there in the lateral aspect of the skull?
The lateral aspect of the skull can be divided into three regions:
How many bones are in the occipital bone?
It is formed by four bones; the frontal bone, the two parietal bones, and the occipital bone. These bones articulate through three sutures: The coronal suture: between the frontal and parietal bones. The lambdoid suture: between the occipital and parietal bones. The sagittal suture: between the two parietal bones.
What is the skull base?
The skull base is the inferior portion of the neurocranium. Looking at it from the inside it can be subdivided into the anterior, middle and posterior cranial fossae. The skull base comprises parts of the frontal, ethmoid, sphenoid, occipital and temporal bones.
What are the components of the brain?
Components and features. The braincase consists of the skullcap ( calvarium) and the skull base. The skull cap is made up of the pairs of parietal bones and parts of the frontal bone as well as the occipital bone. The most important sutures in the human skull are:
What is the facial skeleton?
The facial skeleton is referred to as all skull bones anteroinferior to the cranial cavity. Prominent representatives are the maxilla (upper jaw) and the mandible (lower jaw). The orbita and the nasal cavity are formed by the zygomatic, nasal, palatine, lacrimal bones, the vomer and the inferior nasal concha (lower turbinate).
How many bones are there in the skull?
The human skull consists of 22 bones (or 29, including the inner ear bones and hyoid bone) which are mostly connected together by ossified joints, so called sutures. The skull is divided into the braincase ( neurocr anium) and the facial skeleton ( viscerocranium ).
What are the structures of the infratemporal fossa?
The infratemporal fossa contains several vascular structures: 1 Maxillary artery – the terminal branch of the external carotid artery. It travels through the infratemporal fossa.#N#Within the fossa, it gives rise to the middle meningeal artery, which passes through the superior border via the foramen spinosum. 2 Pterygoid venous plexus – drains the eye and is directly connected to the cavernous sinus.#N#It provides a potential route by which infections of the face can spread intracranially. 3 Maxillary vein 4 Middle meningeal vein
Where is the infratemporal fossa located?
The infratemporal fossa is a complex area located at the base of the skull, deep to the masseter muscle. It is closely associated with both the temporal and pterygopalatine fossae and acts as a conduit for neurovascular structures entering and leaving the cranial cavity.
What muscles are associated with the infratemporal fossa?
The infratemporal fossa is associated with the muscles of mastication. The medial and lateral pterygoids are located within the fossa itself, whilst the masseter and temporalis muscles insert and originate into the borders of the fossa.
What is the fossa?
The fossa is closely associated with both the pterygopalatine fossa, via the pterygomaxillary fissure, and also communicates with the temporal fossa, which lies superiorly (figure 1.0). The boundaries of this complex structure consists of both bone and muscle: Lateral - condylar process and ramus of the mandible bone.
What is the effect of extradural haematoma on the brain?
An extradural haematoma causes a dangerous increase in intra-cranial pressure, which can lead to herniation of brain tissue and ischaemia.
Where are the medial and lateral pterygoids located?
The medial and lateral pterygoids are located within the fossa itself, whilst the masseter and temporalis muscles insert and originate into the borders of the fossa. [caption id="attachment_8575" align="aligncenter" width="512"] Fig 2 - The medial and lateral pterygoids. caption] Nerves. The infratemporal fossa forms an important passage ...
Which pterygoid splits the fossa contents in half?
In fact, the lateral pterygoid splits the fossa contents in half - the branches of the mandibular nerve lay deep to the muscle, while the maxillary artery is superficial to it. Muscles. The infratemporal fossa is associated with the muscles of mastication. The medial and lateral pterygoids are located within the fossa itself, ...
Which part of the anterior cranial fossa is most likely to fracture?
The cribriform plate of the ethmoid is the thinnest part of the anterior cranial fossa, and therefore most likely to fracture. There are two major consequences of cribriform plate fracture: Anosmia - the olfactory nerve fibres run through the cribriform plate, and can be 'sheared', resulting in loss of sense of smell.
What is the frontal bone?
There are several bony landmarks present in the anterior cranial fossa. The frontal bone is marked in the midline by a body ridge , known as the frontal crest. It projects upwards, and acts as a site of attachment for the falx cerebri (a sheet of dura mater that divides the two cerebral hemispheres).
What is the fossa?
The fossa accommodates the anteroinferior portions of the frontal lobes of the brain. In this article, we shall look at the borders, contents and clinical correlations of the anterior cranial fossa. The anterior cranial fossa consists of three bones: the frontal bone, ethmoid bone and sphenoid bone.
What bone is the anterior border of the prechiasmatic sulcus?
Posteriorly and medially it is bounded by the limbus of the sphenoid bone. The limbus is a bony ridge that forms the anterior border of the prechiasmatic sulcus (a groove running between the right and left optic canals).
What are the three depressions in the cranial cavity?
The floor of the cranial cavity is divided into three distinct depressions. They are known as the anterior cranial fossa, middle cranial fossa and posterior cranial fossa. Each fossa accommodates a different part of the brain.
What is the floor of the cranial cavity called?
The Anterior Cranial Fossa. The floor of the cranial cavity is divided into three distinct depressions. They are known as the anterior cranial fossa, middle cranial fossa and posterior c ranial fossa. Each fossa accommodates a different part of the brain.
Which bone contains the main foramina?
The ethmoid bone in particular contains the main foramina (openings that transmit vessels and nerves) of the anterior cranial fossa. The cribriform plate is a sheet of bone seen either side of the crista galli which contains numerous small foramina – these transmit olfactory nerve fibres (CN I) into the nasal cavity.