Figure 6
From: Atlanto-axial rotatory fixation in a girl with Spondylocarpotarsal synostosis syndrome
Sagittal CT image reveals anterior displacement of the odontoid process (O) to the posterior aspect of the anterior arch of C1. Note the Wachenheim clivus line* (a), which is drawn along the posterior aspect of the clivus toward the odontoid process-in our patient – the line does not intersect and is not tangential to the odontoid process-this confirms the abnormality and indicates the existence of occipito-atlas subluxation. The Chamberlain's line **(b) showed no associated basilar invagination.