Consists of three synovial joints. One between odontoid process and anterior arch of atlas, other two between lateral masses of bones
Apical ligament: connects apex of odontoid process to anterior margin of foramen magnum
Alar ligaments: on each side of apical ligament, connect odontoid process to medial sides of occipital condyles
Cruciate ligament: 2 parts – transverse and vertical. Transverse attached to inner aspect of lateral mass of atlas, binds odontoid process to anterior arch of atlas. Vertical from posterior surface body of axis to anterior margin of foramen magnum
Membrana tectoria: upward continuation of posterior longitudinal ligament. Attached above occipital bone within foramen magnum. Covers posterior surface of odontoid process and apical, alar and cruciate ligaments