AN26.1-7 | Skull osteology — Glossary

The H-shaped suture junction of frontal, parietal, temporal, and sphenoid bones; the thinnest part of the skull overlying the middle meningeal artery

A branch of the maxillary artery entering the skull through the foramen spinosum; rupture causes extradural haematoma

A lens-shaped haemorrhage between the skull and dura from middle meningeal artery rupture, classically presenting with a lucid interval

The largest foramen in the skull base transmitting the spinal cord, vertebral arteries, and spinal accessory nerve (CN XI)

The Turkish saddle on the body of the sphenoid bone housing the pituitary gland in the middle cranial fossa

The perforated plate of the ethmoid bone through which olfactory nerve fibres (CN I) pass from the nasal cavity to the anterior cranial fossa

A foramen between the temporal and occipital bones transmitting CN IX (glossopharyngeal), CN X (vagus), CN XI (accessory), and the internal jugular vein

A foramen in the greater wing of the sphenoid transmitting the mandibular nerve (CN V3)

The lower jaw bone with the mental foramen (CN V3), mandibular foramen (inferior alveolar nerve), coronoid process (temporalis), and condylar process (TMJ)

The first cervical vertebra (C1) with no body and no spinous process, supporting the skull via its lateral masses articulating with the occipital condyles

The second cervical vertebra (C2) with the dens (odontoid process) projecting upward, allowing rotational movement of the head

Openings in the transverse processes of cervical vertebrae transmitting the vertebral artery, vein, and sympathetic plexus

The 7th cervical vertebra (C7) with a long non-bifid spinous process that is the most palpable cervical spinous process

The horizontal plane from the lower orbital margin to the upper border of the external acoustic meatus defining the anatomical position of the skull

A dural venous sinus lateral to the sella turcica containing the internal carotid artery and CN III, IV, V1, V2, VI in its wall

The triangle from the bridge of the nose to the corners of the mouth where infections can spread via valveless veins to the cavernous sinus

Direct ossification of mesenchyme without a cartilage precursor, forming flat bones of the skull (frontal, parietal, occipital squamous)

Membranous gaps between skull bones in neonates; anterior (bregma) closes at 18 months, posterior (lambda) at 2-3 months

The junction of the coronal and sagittal sutures; site of the anterior fontanelle in neonates

The junction of the sagittal and lambdoid sutures; site of the posterior fontanelle in neonates

The inferior view of the skull showing the palate, all major foramina, and the three zones of the skull base

A fissure between the greater and lesser wings of the sphenoid transmitting CN III, IV, V1, VI and the ophthalmic veins