Platybasia

**Definition:** A developmental deformity of the occipital bone and upper end of the cervical spine, in which the latter appears to have pushed the floor of the occipital bone upward. (Dorland, 27th ed)

**Tree numbers:** - C05.116.099.742 - C05.116.900.540 - C05.660.207.720 - C16.131.621.207.720

**Synonyms:** - Basilar Impression