The ligaments that limit skull rotation are known as what?

• A. Posterior longitudinal ligaments
• B. Alar ligaments
• C. Anterior ligaments
• D. Transverse ligaments of atlas

Answer: (B)

The ligaments that limit skull rotation are the alar ligaments. They extend from the sides of the dens (odontoid) of the axis to the occipital condyles. When the head tries to rotate, these ligaments tighten and prevent excessive rotation at the atlanto-occipital joint, also helping limit lateral bending of the head. This restraint is different from the transverse ligament of the atlas, which holds the dens against the anterior arch of the atlas to stabilize the atlas–axis relationship, and from the anterior and posterior longitudinal ligaments, which run along the front and back of the vertebral bodies to constrain general flexion and extension along the spine rather than specifically limiting skull rotation.