Assessment of bone union in the cervical spine after the application of a spinal cage.

Background. The aim of our study was to assess interbody bone union in the cervical spine after discectomy and the use of a spinal cage. Material and methods. The clinical material consisted of 117 patients who underwent anterior cervical discectomy and fusion with a Solis cage, packed with bone graft. The subjects were operated in the Department of Neuroorthopedics at the STOCER Rehabilitation Center in 2001-2004. The follow-up ranged from one to three years. One-level fusion was performed in 50% of these cases, two-level in 48%, and three-level in 2%; thus 177 levels were examined. Radiological evaluation included bone union and stiffness of segments without bone union. In clinical examination, pain intensity was evaluated according to the ten-point VAS score. The Neck Disability Index (IND) self- assessment questionnaire was used to evaluate the patients" quality of life. Results. Union was achieved in 90% of the operated spaces. Bone fusion occurred more frequently in multi-level spondylodesis. All the operated interbody spaces in which nonunion occurred were rigid. There was no correlation between the radiological and clinical outcomes. Conclusions. The use of a Solis cage packed with autogenic bone grafts to replace a resected intervertebral disc allows union to be obtained.