[Reduction of periodontoid masses following posterior arthrodesis: review of two new cases not linked to rheumatoid arthritis].

Inflamatory periodontoid pannus is quite common in patients with rheumatoid arthritis. However, the occurrence of a pannus-like periodontoid mass that is unassociated with rheumatic inflammation is less frequent. Transoral surgery associated with a posterior stabilization has long been considered one of the most efficient methods to resolve the problem of instability in patients presenting neurological deficits secondary to the pannus. We present two cases of non rheumatic etiology, in which an occipito-cervical arthrodesis was used to resolve the proliferative lesion around the odontoid apophysis. Two women (67 and 60 years old respectively) presented symptoms of pain and neurological deterioration with an antecedent of possible past odontoid fracture in one case, and a previous large anterior cervical arthrodesis to correct spondylarthrosis in the other case. Both patient's neurological condition improved after placement of an arthrodesis through a posterior approach.