Operative treatment of hangman's fractures of C2. Posterior direct pars screw repair or anterior plate-cage stabilization?

BACKGROUND AND PURPOSE

Feasibility study and evaluation of complications of two different C1-C2 motion-sparing surgical methods for hangman's fracture of C2.

MATERIAL AND METHODS

From 2001 till 2005, seventeen patients were operated on because of unstable type II (according to Effendi) hangman's fractures. The patients were treated either with transoral C2-C3 discectomy with plate-cage stabilization or with posterior direct pars screw repair. The plate-cage group (n=9) comprised patients with a mean age of 34 years, and the average follow-up was 42 months. The screw repair group (n=8) included patients with a mean age of 27 years, and the average follow-up was 28 months. X-rays and computed tomography of the spine were performed before the surgery. X-rays were also performed 2 or 3 days after the surgery, during the 6th week after the surgery as well as at 3, 6, 12, and 24 months thereafter. Fusion and stability of C2 were confirmed on flexion-extension X-rays 6 months after the surgery.

RESULTS

In all patients C1-C2 motion was preserved and bone fusion with good cervical spine alignment was achieved. In the plate-cage group, an extension of the head that is needed to reduce flexion types of fracture can cause technical difficulties with the correct plate-cage installation because of interference of the jaw and tongue in the operative field. One patient of the group experienced a chronic infection which was resolved by plate-cage removal. Patients in the screw repair group healed uneventfully without complications.

CONCLUSIONS

Anterior transoral plate-cage stabilization is indicated for type II fracture with extension displacement and posterior direct pars screw repair for flexion displacement. Nevertheless, posterior direct pars screw repair seems to be safer, cheaper and more technically feasible.