[Cervical spine in polyarthritis. Radiology, indications for surgery and results].

The rheumatoid changes in the spine that are of clinical importance are in the cervical part. They may cause dislocations in the cranio-vertebral region and - more uncommon - in lower levels. Most common is the horizontal dislocation between CI and CII, caused by destruction of the odontoid process and the area around it. This type can progress and give rise to the vertical dislocation caused by bone destruction in the joints between the occiput, CI and CII. The diagnosis is partly clinical and partially made by X-ray films. New radiological methods and new ways of using the old ones are discussed. Subaxial dislocations are not rare. Indications for surgery (fusion and possibly decompression) depend upon the progress of clinical symptoms and radiological findings, as do the surgical methods. The use of bone cement is increasing. Most authors advocate earlier surgical treatment. Subaxial fusion is difficult because of the poor condition of the bone.