Research

Purpose: Prior studies have shown high pseudoarthrosis rates in three or more levels with anterior cervical fusions. We compared the fusion rates of circumferential anterior and posterior to anterior alone fusion for the treatment of cervical spondylotic disease of three or more levels.
Methods. The charts and radiographs of 53 patients were reviewed. Pseudoarthrosis was defined as lack of spanning trabecular bone across host graft interface lateral radiographs or more than 2 mm of motion on flexion/extension radiographs or revision surgery verifying the nonunion at time of surgery. Minimum follow-up for all patients was 2 years.
Results. The two treatment groups were similar with respect to age (average 49 years), percent male (38%) and length of follow-up (28 months). Overall, 68% of the patients had a three-level fusion, 28% had four-level fusion and 4% had five-level fusion; the percent of patients with three, four or five levels fused was similar in the two groups. Solid arthrodesis occurred in 92% (12/13) of AP surgeries and 66% (27/40) of anterior alone. (p=0.023). Although the sample size was limited, no significant difference in fusion rates with regards to use of instrumentation, graft material used, surgical technique, or smoking status was observed. Of the 13 patients who underwent an anterior alone fusion and developed pseudarthrosis, seven were symptomatic enough to undergo revision surgery. All seven underwent revision posterior fusion and had a solid fusion at final follow-up.
Conclusion. A concomitant anterior and posterior fusion results in significantly improved fusion rates (92%) when compared to anterior fusion alone (66%) in treating cervical spine disorders of 3 levels or more.