Intractable nerve pain to the arm caused by a cervical disc herniation is typically treated by removal of the protruding disc through an operation. Fusion of the discs follows in about 70% of cases.~Adjacent disc disease (ADD), symptomatic degenerative changes in the levels adjacent to the operated level is regarded as a late complication. Fusion at the operated level is thought to contribute to this process due to compensative increased mobility and stress on the adjacent segments.~Keeping the operated segment mobile through the use of a cervical disc prosthesis possibly prevents ADD.~We hypothesize that use of a cervical disc prosthesis preserves or restores normal mobility to the cervical spine. To test this hypothesis subjects are randomised in a group receiving a standard anterior cervical discectomy, and a group receiving a standard discectomy with placement of a cervical disc prosthesis. Digital X-ray cinematographic videos are made of a flexion/extension movement. The videos will be analyzed manually and through a newly designed automated program, to check for mobility and order of movement.
The purpose of this study is to find out if use of a cervical disc prosthesis in the treatment of a cervical disc herniation preserves or restores normal mobility and movement in the cervical spine.