Final answer:
A cervical collar limits the movement of the cervical spine, but does not fully immobilize it.
Step-by-step explanation:
A cervical collar is a device used to provide support and immobilization to the cervical spine, which consists of the neck and upper part of the spine. While a cervical collar can help restrict the movement of the cervical spine, it does not fully immobilize it. The collar limits flexion, extension, and lateral flexion of the neck, but it does allow for some rotation.