Transoral atlantoaxial reduction plate fixation for irreducible atlantoaxial dislocation.

OBJECTIVE: To design a clinically applicable transoralpharyngeal atlantoaxial reduction plate (TARP), introduce the operation procedure, and evaluate its preliminary clinical effects. METHODS: A novel TARP system, including butterfly titanium alloy plate, self-locking screws, atlantoaxial reductor and other operational instruments was developed. This system was applied clinically on five patients with irreducible atlantoaxial dislocation of congenital or traumatic origin. During operation, the reduction was completed by the combined action of the plate and the atlantoaxial reductor after transoral joint release and cord decompression. Bone graft granules were implanted between the bilateral atlantoaxial joints and TARP was used to immobilize subsequently the atlas and axis. RESULTS: Clinical application demonstrated that TARP could induce instant reduction and that the method was operationally feasible and its postoperational effect was satisfactory. CONCLUSIONS: The design of TARP is novel. The operational procedure is simple and easy to use. Furthermore, instant reduction can be completed during the operation and the fixation is relatively stable. TARP is an ideal alternative for irreducible atlantoaxial dislocation and may have excellent prospects for further clinical applications.