Treatment of Unstable Lower Cervical Spine Injuries by Anterior Instrumented Fusion Alone

Abstract

STUDY DESIGN: Retrospective study of a prospectively followed cohort. OBJECTIVE: To summarize the complications after instrumented stabilization of cervical spine injuries in a single-institution series, and to discuss management of unstable injuries with respect to the complication rate between the 2 approaches (anterior and posterior). SUMMARY OF BACKGROUND DATA: The anterior approach to the cervical spine has been criticized for destruction of the anterior elements in the presence of posterior instability. The data came mainly from biomechanical studies and older clinical studies with earlier implants. However, there has been growing evidence ever since, that anterior decompression and instrumented fusion alone is an adequate form of treatment for unstable cervical spine injuries. METHODS: Over a 16-year period (1989 to 2005), 112 patients were treated in our institution for unstable cervical spine injuries using either anterior, posterior stabilization, or both. A patient was considered to have an unstable injury if he had 5 points or more in the White and Panjabi instability checklist. At least 1-year follow-up was necessary for a patient to be included in the study, which yielded a total of 97 patients. Seventy-four patients underwent anterior stabilization (group A) and 23 patients underwent posterior stabilization (group B). Three patients in the posterior surgery group required supplemental anterior cervical stabilization. RESULTS: Clinically significant complications occurred in 9/74 (12.2%) patients of group A. Three of 74 patients (4%) were reoperated owing to significant screw backout causing dysphagia, no purchase of the screws being completely in the adjacent disc and screw breakage, respectively. In group B, clinically significant complications were recorded in 4 (17.4%) patients, with an overall reoperation rate of 4% (1/23). Statistical analysis did not reveal significant differences between the 2 groups. CONCLUSIONS: Anterior instrumented fusion is at least as efficient as the posterior procedure in the management of cervical spine injuries and it also has several advantages. Most of such injuries, including the dislocations, can be managed with anterior instrumented fusion alone. Simple means of immobilization such as the hard collar suffice, and secondary posterior fixation is rarely, if ever, necessary.