I — Foramen transversarium; 2 — Transverse process; 3 — Lateral atlanto-axial joint; 4 — Anterior arch; 5 — Superior articular facet; 6 — Alar ligaments; 7 — Posterior atlanto-occipital membrane; 8 — Tectorial membrane; 9 — Apical ligament of dens; 10 — Longitudinal bands;
II — Dens axis [CII]; 12 — Median atlanto-axial joint; 13 — Anterior tubercle of atlas [CI]; 14 -Vertebral body of axis [CII]; 15 — Spinosus process; 16 — Groove for vertebral artery; 17 — Joint capsule; Articular capsule; Lateral atlanto-occipital ligament; 18 — Transverse ligament
of atlas; 19 — Intertransverse ligaments; 20 — Posterior arch; 21 — Ligamentum nuchae; Nuchal ligament
