3-YEAR TO 11-YEAR FOLLOW-UP OF OCCIPITOCERVICAL FUSION FOR RHEUMATOID-ARTHRITIS

The relief of myelopathy usually is unsatisfactory by a conventional G allie type atlantoaxial fusion for patients with rheumatoid arthritis who have irreducible atlantoaxial dislocation. To accomplish a decompr essive laminectomy of the atlas in the treatment of myelopathy, the au thors have been performing a new surgical procedure since 1985 for occ ipitocervical fusion using a rectangular rod. The postoperative outcom es 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 improv ed notably in most cases, and myelopathy was relieved in 12 of 18 (67% ) cases, showing an improvement of more than one level based on Ranawa t's criteria, No serious postoperative complications were seen, except for one case of a failed bone union. The cumulative survival in patie nts with myelopathy was 79.4% in the first 5 years after operation and 27.5% at 10 years. Occipitocervical fusion using a rectangular rod ac companied by a decompressive laminectomy of the atlas can contribute t o the relief of a neurologic deficit in an irreducible atlantoaxial di slocation in rheumatoid arthritis.