Changes in cervical spine curvature and range of motion following a single anterior discectomy without fusion.

Aim. The purpose of the study is to determine the interference of the anterior cervical discectomy without interbody fusion on the long-term curvature of the cervical spine and of its range of motion. Methods. Data obtained from 28 radiographically pre- and post-operatively examined patients were reviewed and statistically elaborated. Participants were selected on the basis of the following criteria: a) a period of at least 3 years between the operation and the radiological study; b) completeness of the radiological study (neutral, flexion and extension views of the cervical spine) before and following surgery; c) absence of any radiological dubious sign of postoperative pseudoarthrosis and/or instability of the operative space. The cervical curvature measurements were carried out according to a modified Cobb method. Results. At the follow-up there was a clear and significant reduction of the lordotic values related to the standard (P<0.01) and extension (P<0.0001) views. On the contrary, mean values of the extreme flexion resulted significantly (P<0.03) reduced, since the increase of the flexion range does not counterbalance the reduction of the extreme extension. Conclusion. Anterior cervical discectomy without fusion was found to reduce the cervical lordotic alignment and the range of motion at a minimum 3-year follow-up. Nevertheless, the authors emphasize that this surgical technique is more successful in safeguarding the cervical curvature and the range of motion than other surgical techniques with both anterior or posterior approaches.