Concomitant alar and apical ligament avulsion in atlanto-axial rotatory fixation. Case report and review of the literature.

The authors report a case of Fielding type II acute atlanto-axial rotatory fixation (AARF). The CT scan with coronal reconstruction showed an avulsion of the apical and right alar ligament. These findings are exceptionally reported in the literature, especially concerning the apical ligament which might be a stabiliser in flexion and extension of the occipitocervical joint.