Occipito-cervical fusion with the cervical Cotrel-Dubousset rod system

Diseases and conditions which cause instability of the craniocervical junction and the adjacent upper cervical spine are relatively common and potentially life-threatening. Direct internal occipitocervical fusion (OCF) is a modern means of surgical treatment in such cases, and has some advantages over simple immobilization of the affected segments. The present study was designed to evaluate surgical handling, results, and complications with a recently developed instrumentation for OCF, the Cotrel-Dubousset rod-and-hook system (CD). Fourteen consecutive patients with occipito-cervical instability due to fractures, degenerative or neoplastic disease or malformations underwent OCF with the CD system. Autologous or allogeneic bone and bone substitutes such as hydroxyapatite were used to augment the CD fusion. Patients were followed clinically and neuroradiologically for 1 to 4 years (mean 20 months). Assessments were routinely performed at 1 week, 1 month, 3 months, 1/2 year, and every year after surgery. There was no immediate surgery-related morbidity or mortality, and no major late complications due to hardware failure. A stable bony fusion according to radiological criteria was achieved in all cases. No implant breaks or loosening and dislocation of the hooks or the screws were encountered. In no case did neurological deterioration occur after surgery. Short-term evaluation at 1 week after surgery showed no difference with respect to neurological symptoms as compared with the pre-operative findings, except for a patient reporting improvement of paraesthesia on the first postoperative day. The long-term effects were, however, beneficial to most patients, as the fusion alleviated neck pain in 13 cases and improved neurological deficits in 3 of the 4 cases with pre-operative motor weakness or paraesthesia. In conclusion, internal OCF with the CD system, an implant which is easy to handle and safe for the patient, is a technique with a high rate of successful bony fusion. Since no halo placement is needed after surgery, patients have considerable gain of quality of life as compared to other standard surgical techniques.