Volume-Outcome Relationship After 1 and 2 Level Anterior Cervical Discectomy and Fusion

Objective To investigate the effects of surgeon volume on inpatient morbidity after 1- and 2-level anterior cervical discectomy and fusion (ACDF). Methods Data from the Nationwide Inpatient Sample from 2009 were extracted. All adult patients who underwent an elective 1- or 2-level ACDF for degenerative cervical spine disease were identified. Surgeon volume was analyzed as a continuous and categorical variable: very low (<12 procedures per year), low (12–23 procedures per year), medium (24–35 procedures per year), high (36–47 procedures per year), and very high (≥48 procedures per year). A multivariate logistical regression analysis was performed to calculate the adjusted odds ratios of overall in-hospital and surgical complication occurrence in relation to surgeon volume. Results Eleven thousand two hundred forty-nine admissions were analyzed. The overall complication rate was 4.7%, and the surgical complication rate was 1.2%. Following regression analysis, increasing surgeon volume (evaluated continuously) was independently associated with lower odds of overall complication (odds ratio [OR], 0.99; 95% confidence interval [CI], 0.98–0.99; P < 0.001) and surgical complication development (OR, 0.98; 95% CI, 0.97–0.99; P = 0.004). Surgeons with very high volume (performing 48 or more procedures per year; 4 or more per month) showed a significant decrease in overall complications (OR, 0.58; 95% CI, 0.41–0.84; P = 0.003) and surgical complications (OR, 0.52; 95% CI, 0.25–0.99; P = 0.041) when compared to surgeons with very low volume. Conclusion In this study, increasing surgeon volume was independently associated with significantly lower odds of perioperative complications following 1- and 2-level ACDF. Performing 4 or more procedures per month was associated with the lowest complication rate.