[Reosteosynthesis in dens pseudarthrosis. Case report and review of the literature].

According to general recommendations, unstable nonunions of the odontoid are treated by posterior fusion of the segments C1/C2 and transarticular screwosteosynthesis. The aim of the surgical procedure is to obtain secure reduction stabilization, and fusion of the nonunion. We present a case of secondary atlanto-axial instability treatment following of an odontoid nonunion. In this situation stability of C1/C2 was achieved by atlanto-axial fusion by transarticular screw fixation. The ventral parts of the broken implants were left in place. Diagnosis, treatment and complications of pseudarthrosis of the dens axis are discussed in the context of this case and of literature.