A prospective study of the progression of rheumatoid arthritis of the cervical spine

This prospective study was begun in 1974 to determine the progression of rheumatoid arthritis of the cervical spine. Of 163 patients with complaints about the cervical spine followed in the Arthritis Clinic, 106 were available for study five years later. At the start of this study, forty-six (43 per cent) of these 106 patients already had radiographic evidence of rheumatoid involvement of the cervical spine, consisting of atlanto-axial subluxation in twenty-eight (61 per cent), atlanto-axial subluxation combined with subaxial subluxation in nine (20 per cent), and subaxial subluxation alone in five (11 per cent). The remaining four patients (8 per cent) had combinations of these findings together with superior migration of the odontoid process. At the end of the study, seventy-four (70 per cent) of the patients had radiographic evidence of cervical involvement, primarily of the combined type. Twenty-one patients died during the period of follow-up. None of the known causes of death could be attributed to disease of the cervical spine. Three features of rheumatoid cervical disease were evaluated: pain, neural involvement, and radiographic abnormalities. Although all three features were progressive, radiographic deterioration was a more prominent feature than progressive neural dysfunction. At the final evaluation, the disease in twenty-seven (36 per cent) of the patients was noted to have progressed neurologically while in sixty patients (80 per cent) it had progressed radiographically. Pain was the only feature of the disease that showed any tendency to improve. The development of subaxial subluxation or superior migration of the odontoid process in a patient with pre-existing atlanto-axial subluxation was found to be a bad prognostic sign. Spontaneous apophyseal fusion occurred in four patients (3.8 per cent). In one of these there was an improvement in the neural status and in another, progressive dysfunction followed. Seven of the seventy-four patients who had radiographic involvement by the end of study underwent surgical stabilization for severe neural dysfunction. Only one of the seven had had no radiographic findings at the beginning of the study; thus, six (13 per cent) of the patients who had radiographic involvement initially ultimately came to surgical stabilization for pain and instability associated with neural dysfunction.