What are the parts of the ethmoid bone?

What are the parts of the ethmoid bone?

The ethmoid bone is made up of three parts – the cribriform plate, the perpendicular plate, and the ethmoidal labyrinth. The cribriform plate forms the roof of the nasal cavity. It is pierced by numerous olfactory nerve fibres, which gives it a sieve-like structure.

What is the function of ethmoid bone?

The ethmoid bone is a singular porous bone that makes up the middle area of the viscerocranium and forms the midfacial region of the skull. It contributes to the moulding of the orbit, nasal cavity, nasal septum and the floor of the anterior cranial fossa.

What is the perpendicular plate of the ethmoid bone?

The perpendicular plate of the ethmoid bone (vertical plate) is a thin, flattened lamina, polygonal in form, which descends from the under surface of the cribriform plate, and assists in forming the septum of the nose; it is generally deflected a little to one or other side.

What is the purpose of the Cribriform plate?

The cribriform plate is the portion of the ethmoid bone that forms the roof of the nasal cavity. This narrow bony structure contains deep grooves known as olfactory fossa, which supports the olfactory bulb.

What is the space between your nostrils called?


Which areas of the skull are formed in part by the ethmoid bone?

Which areas of the skull are formed in the part by the ethmoid bone? Anteromedial floor of cranium, roof of the nasal cavity, part of the medial wall of each orbit, and part of the nasal septum.

What is the strongest part of the skull?


Which part of the skull is the hardest?

temporal bones

Which bone is not considered to be part of the cranium?

lacrimal bone

Is the ethmoid bone is a facial bone?

The facial bones of the skull form the upper and lower jaws, the nose, nasal cavity and nasal septum, and the orbit. Although classified with the brain-case bones, the ethmoid bone also contributes to the nasal septum and the walls of the nasal cavity and orbit.

Which facial bones form the roof of the mouth quizlet?

The maxillary bone makes up about 3/4 of the hard palate, or the bony roof of the mouth.

Which foramen convey a branch of the trigeminal nerve?

Foramen Rotundum. The foramen rotundum is located at the base of the greater wing of the sphenoid, inferior to the superior orbital fissure. It provides a connection between the middle cranial fossa and the pterygopalatine fossa. The maxillary nerve (branch of the trigeminal nerve, CN V) passes through this foramen.

Which is the largest branch of the trigeminal nerve?

mandibular nerve

What nerve passes through the Stylomastoid foramen?

The facial nerve then exits the facial canal (and the cranium) via the stylomastoid foramen. This is an exit located just posterior to the styloid process of the temporal bone. Fig 2 – Schematic of the course and branches of the facial nerve.

What nerve passes through the jugular foramen?

The glossopharyngeal, vagus, and accessory nerves pass through the jugular foramen on the medial side of the jugular bulb.

What is directly lateral to the jugular foramen?

Closely medial to the jugular foramen sits the hypoglossal canal, which itself is directly lateral to the foramen magnum bilaterally. Superior to the groove of the sigmoid sinus sits the superior margin of the petrous, in which the superior petrous sinus lies.

What is jugular foramen syndrome?

The jugular foramen syndrome (JFS) (Vernet syndrome) refers to paralysis of the IX, X, and XI cranial nerves traversing the jugular foramen. Safe resection is the treatment of choice in benign tumors.

What does the jugular foramen transmit?

The jugular foramen (JF) is a bony channel that transmits vessels and cranial nerves IX, X, and XI (CNIX, CNX, and CNXI) through the skull base into the carotid space.

What goes through the foramen Lacerum?

Function. The artery of pterygoid canal, the nerve of pterygoid canal and some venous drainage pass through the foramen lacerum. Furthermore, one of the terminal branches of the ascending pharyngeal artery (itself a branch of the external carotid artery) passes through the foramen lacerum.

Is the jugular foramen larger than the foramen magnum?

Foramina, canals, and fissures serve as passageways for blood vessels and nerves. The jugular foramen is larger than the foramen magnum.

How do you memorize the skull foramen?

A mnemonic phrase that I’ve used to help remind us of the anatomical locations and names of the paired foramina in the cranial floor is this: Old Rotund Owls Spin Lazily Across Jugs.

What is the largest foramen in the skull?

The foramen magnum is the largest foramen of the skull. It is located in the most inferior portion of the cranial fossa as a part of the occipital bone.

Which bone is the most posterior skull bone?

occipital bone

Does spinal cord pass through foramen magnum?

It is one of the several oval or circular openings (foramina) in the base of the skull. The spinal cord, an extension of the medulla oblongata, passes through the foramen magnum as it exits the cranial cavity.

What is the hole in the back of your skull called?

There is a large opening, called the foramen magnum, located in the back of the occipital bone. This is where the medulla ends and projects out of the skull. Smaller holes in the skull, called foramina, allow nerves and blood vessels to enter and leave the cranium.

What is the hole at the bottom of the skull called?

On the bottom of your skull, there is a distinctive hole. The technical name for the opening is the foramen magnum – the “great hole” that the spinal cord and other critical soft tissues run through.

What is a foramen magnum decompression?

Foramen magnum decompression involves removing a small part of the base of the skull and sometimes parts of the top of the spine to take the pressure off the cerebellum. Before the surgery, your surgeon will take a look at your medical history and walk you through the surgery and the associated risks.

Is Chiari progressive?

In some people, Chiari malformation can become a progressive disorder and lead to serious complications. In others, there may be no associated symptoms, and no intervention is necessary. The complications associated with this condition include: Hydrocephalus.

Is Chiari a disability?

If you have Arnold-Chiari Malformation that has resulted in severe symptoms that have made you unable to work, you may be eligible to receive Social Security disability benefits. A chiari malformation (CM) is a defect in the brain structure.

Does Chiari 1 malformation get worse?

If you have been diagnosed with Chiari malformation, one of the first questions you may have is, “Can Chiari malformation get worse?” The simple answer is, yes, it can, which is why many (though not all) patients will require treatment.


Andrey is a coach, sports writer and editor. He is mainly involved in weightlifting. He also edits and writes articles for the IronSet blog where he shares his experiences. Andrey knows everything from warm-up to hard workout.