What passive movement can be performed at the head to change tension in the ligamentum nuchae?

To change tension in the ligamentum nuchae, the passive movement that is most effective is flexion and extension of the head. The ligamentum nuchae is a fibrous structure that runs from the external occipital protuberance down to the cervical vertebrae, playing a crucial role in stabilizing the head and providing support to the neck.

When flexion occurs, the head moves forward, which exerts a different tensile force on the ligamentum nuchae compared to when the head is in an extended position, where the chin is lifted. This change in position alters the length and tension experienced by the ligament. Flexion and extension are fundamental movements of the cervical spine that directly impact the posture and mechanical strain on the structures associated with the neck, including the ligamentum nuchae.

Other movements like lateral flexion and rotation primarily affect other muscles and joints surrounding the cervical spine, but do not specifically target the tension changes in the ligamentum nuchae as flexion and extension do. Abduction and adduction are movements related to the limbs rather than the head and neck, further establishing why they would not be applicable in this context.