Sphenoid bone

The sphenoid bone (os sphenoidale, pna, bna; os sphenoides, jna) is an unpaired bone of the base of the skull, located in its middle part. It has a complex shape and consists of a body and processes extending from it.

The body of the bone has the shape of an irregular cube with edges facing anteriorly, posteriorly, upwardly and downwardly. Two pterygoid processes extend from the anterior surface of the body, limiting the lateral fossa of the sphenoid bone. The basilar part, which participates in the formation of the base of the skull, extends from the posterior surface. Large wings extend from above the body and participate in the formation of the cranial cavity. Below are two small wings and two sphenoid processes, which take part in the formation of the pterygopalatine and sphenoid fossae.

The sphenoid bone connects to other bones of the skull, forming its base and participating in the formation of the base and vault of the skull. Nerves and vessels pass through the holes and crevices of the bone, connecting the cranial cavity with the facial part of the head. Bone plays an important role in transmitting pressure from the brain to the base of the skull.