3- to 11-year followup of occipitocervical fusion for rheumatoid arthritis.

The relief of myelopathy usually is unsatisfactory by a conventional Gallie type atlantoaxial fusion for patients with rheumatoid arthritis who have irreducible atlantoaxial dislocation. To accomplish a decompressive laminectomy of the atlas in the treatment of myelopathy, the authors have been performing a new surgical procedure since 1985 for occipitocervical fusion using a rectangular rod. The postoperative outcomes for 25 patients with rheumatoid arthritis were evaluated clinically and radiographically with a 3- to 11-year (mean, 6.5 years) followup. A decompressive laminectomy of the atlas accompanied the fusion in 21 of the 25 patients. The incidence of occipital or nuchal pains improved notably in most cases, and myelopathy was relieved in 12 of 18 (67%) cases, showing an improvement of more than one level based on Ranawat's criteria. No serious postoperative complications were seen, except for one case of a failed bone union. The cumulative survival in patients with myelopathy was 79.4% in the first 5 years after operation and 27.5% at 10 years. Occipitocervical fusion using a rectangular rod accompanied by a decompressive laminectomy of the atlas can contribute to the relief of a neurologic deficit in an irreducible atlantoaxial dislocation in rheumatoid arthritis.