Rate of Return to Military Active Duty After Single Level Lumbar Interbody Fusion: A 5-Year Retrospective Review

BACKGROUND: Lumbar interbody fusion has been extensively studied in the civilian population; however, data regarding its efficacy in the military are lacking. OBJECTIVE: To identify the rate of return to unrestricted active military duty after single-level lumbar interbody fusion surgery. METHODS: The surgical database at a single tertiary care military treatment facility was queried for active-duty patients who underwent a single-level lumbar interbody fusion over a 5-year period. A retrospective chart review was performed with backward stepwise logistic regression analysis, and Fisher exact and Wilcoxon rank sum tests were used for statistical analysis. RESULTS: A total of 102 patients met the inclusion criteria. Mean age at surgery was 34.0 years (range, 19-51 years). Most surgeries (59%) were performed for discogenic pain secondary to degenerative disc disease; the remaining patients underwent surgery for spondylolisthesis (39%) or spinal stenosis (2%). Thirty-nine patients (38%) were treated via an anterior approach (anterior lumbar interbody fusion), whereas 63 patients (62%) underwent fusion via a posterior approach (transforaminal or posterior lumbar interbody fusion). Fifty-six patients (55%) were able to return to unrestricted full active duty, and the remaining 46 patients (45%) were separated from the military. The return to active duty rate was significantly higher in older patients and those ranking E7 (Chief Petty Officer) and above (84.8%). CONCLUSION: Fifty-five percent of the service members who underwent a single-level lumbar interbody fusion returned to unrestricted full duty. Older age and higher rank were statistically significant positive predictors of a successful return to active duty.