Surgical treatment of os odontoideum

Os odontoideum is a rare disease. There have been few reports of os odontoideum in the literature. In this study we retrospectively reviewed eight surgically treated patients. One patient underwent C1–2 transarticular screw fixation, five patients underwent C1–2 polyaxial screw and rod fixation and two patients with dystopic os odontoideum underwent occipito-cervical (O-C) fusion. Of the eight patients, neck pain was alleviated in seven (87.5%). Of the six patients who had neurological signs and symptoms, five (83.3%) exhibited neurological improvement. Radiologically, solid fusion was observed in seven patients (87.5%). Active surgical treatment should be considered even in patients with os odontoideum who exhibit mild symptoms. In most patients with os odontoideum, use of the C1–2 polyaxial screw and rod technique may be the most appropriate treatment. In patients with dystopic os odontoideum, O-C fusion should be considered.