Anterior Reduction and C1-ring Osteosynthesis With Jefferson-fracture Reduction Plate (JeRP) via Transoral Approach for Unstable Atlas Fractures

Abstract Objective:To introduce a novel transoral instrumentation in the treatment of unstable fractures of atlas.Methods: From January 2008 to May 2018, 22 patients with unstable C1 fractures were retrospective analyzed, who received Jefferson-fracture reduction plate (JeRP) via transoral approach. The case history and the radiographs before and after surgery were noted. The type of fracture, the reduction of the fracture and position of the internal fixation were assessed by preoperative and postoperative CT scans.RESULTS: All 22 patients successfully underwent anterior C1-ring osteosynthesis using JeRP system, with a follow-up of 26.84±9.23 months. Among them, 9 patients had transverse atlantal ligament (TAL) injury, including 3 in Dickman type I and 6 in type II. The preoperative lateral mass displacement (LMD) decreased from 7.13±7.08 mm to 1.02±0.65 mm after operation. Bone union was achieved in all patients without implant failure or loss of reduction. There were no surgery-related complications, such as wound infection, neurological deficit, or vertebral artery injury. However, 3 patients with Dickman type I TAL injury occured atlantoaxial dislocation 3 months postoperatively without any neurological symptoms or neck pain.CONCLUSIONS: Transoral C1-ring osteosynthesis with JeRP is an effective surgical strategy of unstable atlas fractures, achieving direct and satisfactory reduction safely. The primary indication for JeRP system is an unstable fracture (Gehweiler type I/III) or/ and TAL injury (Dickman type II).