Posterior screw-plate system for treating old fracture of the odontoid process.

Objective: To assess the efficacy of a screw-plate system for the treatment of old fracture of the odontoid process.

Methods: Twenty-six patients with old fracture of the odontoid process were treated by a posterior screw-plate system. There were 17 men and 9 women ranging in age from 17 to 58 years (mean, 32.8 years). According to the Anderson-D'Alonzo classification, 19 patients were classified as type II, and 7 as type III. According to the Frankel classification, there were 3 patients of grade C, 21 of grade D and 2 of grade E.

Results: All operations were successfully performed. The operation time was 75-120 min (mean, 90 min) and the intraoperative blood loss 50-200 ml (mean, 125 ml). There were no postoperative complications. All patients were followed up for 24-36 months. At the final follow-up, one patient had improved from grade C to grade D, two from grade C to grade E, and 15 from grade D to grade E. The other cases had remained stable. There was no breakage of nails or failure of internal fixation during follow-up. Stable bone union was observed in all cases, the average healing time being 7.8 months.

Conclusion: Posterior screw-plate system is a safe and effective method for treating old fracture of the odontoid process.