To evaluate the efficacy of upper cervical spine surgery in symptomatic atlantoaxial instability due to rheumatoid arthritis (RA).
Thirty RA patients (29 women and one man) with a mean age of 56 years were studied retrospectively. Symptomatic forward slippage of the atlas on the axis with a synovial pannus surrounding the odontoid and magnetic resonance imaging evidence of spinal cord compression was present in all 30 patients; 18 patients had vertical translocation of the odontoid and 14 had basilar invagination. Surgery, performed between 1991 and 1997, consisted of occipitocervical fusion in 18 patients and atlantoaxial fusion in 12. Cotrel-Dubousset instrumentation was performed in all 30 patients.
Mean follow-up was four and a half years. All patients were satisfied with the procedure and exhibited marked functional gains and objective neurological improvement (by one class in the Ranawat scheme). Stable fusion was documented in all 30 patients.
Cervical instrumentation and bone grafting seems to provide functional and neurological gains in carefully selected RA patients with atlantoaxial instability and spinal cord compression. Long term follow-up suggests that the benefits are sustained and that morbidity is low.