Pterygoid processes of the sphenoid

The pterygoid processes of the sphenoid, one on either side, descend perpendicularly from the regions where the body and great wings unite.

Each process consists of a medial pterygoid plate and a lateral pterygoid plate, the upper parts of which are fused anteriorly; a vertical sulcus, the pterygopalatine groove, descends on the front of the line of fusion.

The plates are separated below by an angular cleft, the pterygoid fissure (or pterygoid notch), the margins of which are rough for articulation with the pyramidal process of the palatine bone.

The two plates diverge behind and enclose between them a V-shaped fossa, the pterygoid fossa, which contains pterygoideus internus and tensor veli palatini.

Above this fossa is a small, oval, shallow depression, the scaphoid fossa, which gives origin to the tensor veli palatini.

The anterior surface of the pterygoid process is broad and triangular near its root, where it forms the posterior wall of the pterygopalatine fossa and presents the anterior orifice of the pterygoid canal.

In many mammals it remains as a separate bone called the pterygoid bone.

Its name is Greek for "resembling a fin or wing", from its shape.

Additional images

References

External links

• Roche Lexicon - illustrated navigator, at Elsevier 34257.000-1

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained within it may be outdated.