Osteology of the Skull Practice Flashcards

Vocabulary-style flashcards covering the osteology, landmarks, and foramina of the human skull according to lecture notes.

Cranium

The skeleton of the head, consisting of the neurocranium and viscerocranium.

Neurocranium

The bony case of the brain and its membranous coverings, formed by 8 bones: frontal, ethmoidal, sphenoidal, occipital, and bilateral temporal and parietal bones.

Viscerocranium

The facial skeleton comprising 15 irregular bones, including the mandible, ethmoid, vomer, and bilateral maxillae, zygomatic, and nasal bones.

Calvaria

The dome-like roof of the neurocranium, also known as the skullcap.

Basicranium

The floor or cranial base of the neurocranium, primarily formed by irregular bones with flat portions like the sphenoid and temporal bones.

Ethmoid bone

An irregular bone that makes a minor midline contribution to the neurocranium but is primarily part of the viscerocranium.

Synchondroses

Hyaline cartilage that unites certain bones of the neurocranium, such as the sphenoid and occipital, during childhood.

Alveolar processes

The parts of the maxillae and mandible that contain tooth sockets (alveoli) for the maxillary and mandibular teeth.

Pterion

An H-shaped formation of sutures on the lateral aspect of the skull where the frontal, parietal, sphenoid (greater wing), and temporal bones unite.

External occipital protuberance

A prominent landmark on the occipital aspect of the cranium; its tip defines the craniometric point known as the inion.

Lambda

The junction of the sagittal and lambdoid sutures at the center of the occiput.

Bregma

The craniometric landmark formed by the intersection of the sagittal and coronal sutures.

Vertex

The most superior point of the calvaria, located near the midpoint of the sagittal suture.

Hard palate

Bony structure formed by the palatine processes of the maxillae anteriorly and the horizontal plates of the palatine bones posteriorly.

Incisive foramen

A depression in the midline of the bony palate posterior to the central incisor teeth where the incisive canals open.

Choanae

Two large openings known as posterior nasal apertures, separated by the vomer bone.

Sella turcica

A formation on the sphenoid bone within the middle cranial fossa, composed of the tuberculum sellae, hypophysial fossa, and dorsum sellae.

Optic canal

Opening in the sphenoid bone that transmits the optic nerve ($CN\,II$) and ophthalmic artery.

Superior orbital fissure

Opening that transmits $CN\,III, IV, V_1$ (ophthalmic branch of trigeminal), $VI$, and ophthalmic veins into the orbit.

Foramen rotundum

Opening in the middle cranial fossa that transmits the maxillary branch of the trigeminal nerve ($CN\,V_2$).

Foramen ovale

Opening in the middle cranial fossa that transmits the mandibular branch of the trigeminal nerve ($CN\,V_3$) and the accessory meningeal artery.

Foramen magnum

The large opening in the occipital bone transmitting the medulla, meninges, vertebral arteries, and spinal accessory nerve ($CN\,XI$).

Jugular foramen

Opening situated on either side of the foramen magnum that transmits $CN\,IX, X, \text{and } XI$.

Hypoglossal canal

Opening immediately superior to the anterolateral margin of the foramen magnum transmitting the hypoglossal nerve ($CN\,XII$).

Asterion

A star-shaped junction of the parietomastoid, occipitomastoid, and lambdoid sutures.

Glabella

The smooth prominence on the frontal bone superior to the root of the nose; the most anterior projecting part of the forehead.

Cribriform plate

Part of the ethmoid bone with small foramina that transmit olfactory nerve ($CN\,I$) fibers and support the olfactory bulb.

Internal acoustic meatus

An oval opening in the petrous part of the temporal bone that transmits $CN\,VII$ and $CN\,VIII$.