Sphenoid bone

Function

The keystone of the cranial base — every other cranial bone articulates with it. Its sella turcica cradles the pituitary gland, its wings form the orbit walls, and its foramina conduit the trigeminal branches and middle meningeal artery.

Landmarks

• Sella turcica (pituitary fossa)
• Greater and lesser wings
• Optic canal
• Superior orbital fissure
• Pterygoid processes
• Foramen rotundum
• Foramen ovale
• Foramen spinosum

Articulations (joints)

• Frontal bone
• Parietal bones
• Temporal bones
• Occipital bone
• Ethmoid bone
• Zygomatic bones
• Palatine bones
• Vomer
• Maxillae

Clinical relevance

Pituitary adenomas erode the sella and press on the optic chiasm causing bitemporal hemianopia. Surgeons reach the pituitary through the sphenoid sinus (transsphenoidal approach).