[Transoral plate internal fixation for treatment of instability atlas fracture].

Objective: To evaluate the efficacy and safety of transoral plate internal fixation for instability atlas fracture.

Methods: A retrospective study was performed in eight patients with instability atlas fractures, who were treated by a transoral plate internal fixation from July 2007 to June 2011. There were 6 males and 2 females,with an average age of 39.5 years old ranging from 23 to 48 years. Among them, 5 case were falling injury, 3 cases were traffic accident injury. Three patients had bilateral fractures of the anterior arch (prehalf Jefferson fractures, Landells type I), 5 had anterior are fracture associated posterior are fracture (Half-ring Jefferson fractures, Landells type II), and 2 had anterior and posterior are fracture associated with single lateral mass fractures (Landells type III).

Results: All patients were followed up for 6 to 24 months after operation (av- eraged 13 months), and all the patients had the clinical symptoms improved to some extent. Operation time ranged from 80 to 140 min (averaged 98 min); the intra-operative blood loss was 120 to 300 ml (averaged 180 ml); and the average fluoroscopic time was 55 s. No patients happened neurological and vertebral artery injuries-related complications or other complications after operation. The followed-up X-ray and CT manifested osseous fusion in all the 8 patients,no loosening or breakage of the screws.

Conclusion: Transoral plate internal fixation for instability atlas fracture is a reliable and safety technique that allows maintenance of rotatory mobility in the C1,2 joint and restoration of congruency in the atlanto-occipital and atlanto-axial joints.