Duplication of the occipital condyles.

This article describes an extremely rare case, encountered in the anatomy laboratory, of a skull base found to have duplication of both occipital condyles. In addition, this specimen was noted to have a large bony excrescence near the basion, a small third occipital condyle, a left paracondylar process, elongation of the right styloid process, and a bony septation of both hypoglossal canals. The embryology and clinical implications are discussed.