[Rheumatoid arthritis of the cervical spine: surgical management].

Cervical spine involvement in patients suffering from rheumatoid arthritis significantly increases with time. This progression results in C1-C2 instability, vertical subluxation, subaxial spine subluxation or a combination of those three types of instability. It can remain asymptomatic or present with pain and/or neurological symptoms. Surgical treatment could be indicated in the presence of C1-C2 instability greater than 6 mm or even grater than 3 mm if there is associated vertical subluxation. Surgery can be associated with significant mortality and morbidity. In the presence of myelopathy surgical results can be particularly unfavourable with a mortality as high as 50%. It seems therefore important to proceed to surgical stabilisation quite early in order to prevent the onset of neurological involvement. Primary fusion extending to the upper thoracic spine should also be considered in selected patients in order to avoid the onset of caudal instability which can present with late development of progressive myelopathy.