Trends in lumbar interbody fusion: A study of American Board of Orthopedic Surgery (ABOS) candidate data

Abstract

Background: There has been an increase in posterior-based interbody fusions over the past two decades. Our objective was to evaluate trends in interbody fusion use among the American Board of Orthopedic Surgery (ABOS) Part II candidates. Methods: The ABOS database from 2003 to 2012 was queried for common procedural terminology (CPT) codes indicating lumbar interbody fusion (22,558 anterior lumbar interbody fusion [ALIF] and 22,630 and 22,633 posterior lumbar interbody fusion [PLIF] or transforaminal lumbar interbody fusion [TLIF]). Trends in the use of interbody fusion technique, associated complications, and geographical variation were evaluated. We also queried utilization of the anterior and posterior interbody fusions by the International Classification of Diseases-9 code. Results: 6841 interbody fusion cases were identified (2329 ALIF and 4512 PLIF/TLIF). There was a significantly higher use of PLIF/TLIF than ALIF over the study period (P < 0.001). As compared to patients in the Midwest, those in the Northwest had significantly higher odds of undergoing PLIF/TLIF (odds ratio [OR]: 4.79, 95% confidence interval [CI]: 3.61–6.35, P <0.001), and those in the Southwest had significantly lower odds of PLIF/TLIF (OR: 0.81, 95% CI: 0.69–0.95, P = 0.01). The overall complication rate was 22.2% (n = 1,519). Vascular-related complications were significantly higher among patients undergoing ALIF (31 vs. 1, P <0.001), while those undergoing TLIF/PLIF were more likely to experience unspecified medical complications. On multivariate analysis, patients undergoing PLIF/TLIF had lower odds of experiencing a complication (P = 0.03, OR 0.87, CI 95%). Conclusion: Over the 10-year study period, there has been a significantly increased rate of posterior interbody fusion among candidates taking part II ABOS examination.