Computed tomography of the craniocervical junction in rheumatoid arthritis.

Thirty-three patients with rheumatoid arthritis had computed tomographic examination of the craniocervical junction. This demonstrated soft tissue features which have not previously been described in published reports. A low attenuation lesion between the odontoid and the transverse ligament shown in 11 patients was considered a premonitory sign of rupture of the transverse ligament or a manifestation of active disease. Computed tomography revealed spinal cord compression in 3 patients and ligamentous changes in the transverse ligament and the alar and spinal ligaments in 26 patients. Erosion of the odontoid was shown in 19 patients and subluxation in 20 patients. No relationship could be found between the clinical signs and symptoms and the radiological abnormalities except in the case of cord compression.