What motion does the ligamentum nuchae primarily restrict?

The ligamentum nuchae is a fibrous structure that extends from the external occipital protuberance at the base of the skull down to the spinous processes of the cervical vertebrae. Its primary function is to support the head and neck and to limit excessive motion.

The ligamentum nuchae primarily restricts flexion. When an individual flexes the neck forward, this structure provides resistance, ensuring stability and preventing hyperflexion. By limiting this forward bending motion, the ligamentum nuchae helps maintain proper alignment and function of the cervical spine, contributing to postural balance and the prevention of injury.

In the context of the other options, while the ligamentum nuchae can play a role in limiting excessive rotation, extension, and lateral bending, its main focus is on restricting flexion due to its anatomical location and orientation. Therefore, the correct understanding of the ligamentum nuchae's role emphasizes its primary function in limiting flexion of the cervical spine.