Transoral reduction and osteosynthesis C1 as a function-preserving option in the treatment of unstable Jefferson fractures.

STUDY DESIGN: Retrospective study with clinical and radiologic evaluation of transoral reduction and osteosynthesis of C1 in the treatment of unstable Jefferson fractures.

OBJECTIVE: Assessment of a new method, which preserves the function of the C1-C2 joint in young patients.

SUMMARY OF BACKGROUND DATA: Unstable Jefferson fractures with rupture of the transverse ligament and high-grade dislocation of the lateral masses of C1 are usually treated conservatively by immobilization or traction or surgical by posterior fusion C1-C2.

METHODS: Six patients with Jefferson fractures with rupture of the transverse ligament were treated by a transoral approach. Reduction was performed by direct manipulation followed by the osteosynthesis of the anterior ring and the lateral masses of C1.

RESULTS: Total average lateral displacement of the lateral masses was 13.5 mm before surgery (range, 8-19 mm) and improved to 4.3 mm after surgery (range 1-8 mm). The total average difference of the atlantal-dens interval in flexion-extension after surgery was 2.0 mm (range 1-3 mm). The average postoperative rotation in the atlantoaxial joint, evaluated by rotation MRI, was in total 39.2 degrees (range 10 degrees - 61 degrees).

CONCLUSIONS: Transoral reduction and osteosynthesis C1 is a new technique that allows maintenance of rotatory mobility in the C1-C2 joint and restoration of congruency in the atlanto-occipital and atlantoaxial joints. None of the patients had symptoms of postoperative instability of C1-C2.