Unplanned return to the operating room (UPROR) after surgery for adolescent idiopathic scoliosis

Study design Retrospective analysis of a prospectively collected multi-center database. Purpose UPROR (Unplanned Return to the Operating Room) is an inclusive metric for unexpected surgery after the index procedure. Given the many quality and safety improvements in AIS surgery over the past 20 years, it is useful for spine deformity surgeons to understand the current rate of UPROR, the etiologies, and trends over time. A report from a very large data set, including multiple surgeons and centers, with longer follow-up, would provide the clearest picture. Methods We performed a retrospective review of a prospective multi-center database of patients who had AIS deformity correction surgery to analyze all cases of UPROR, using linear regression models, survival analysis, and descriptive statistics. Results Among 3464 patients who had surgery (ASF, PSF, or ASF + PSF) for AIS from 1995 to 2017, 4.8% had an UPROR event in one of the following categories: surgical-site-related (43.3%), instrument failures (34.3%), revisions (8.4%), neurologic (5.1%), pulmonary (5.1%), medical (0.6%), and other (3.4%). The average time from initial surgery to UPROR was 734.4 days. 45.5% of UPRORs occurred within 1 year, 12.4% between 1 and 2 years, 30.9% between 2 and 5 years, and 11.2% between 5 and 10 years. In patients with at least 2-year, 5-year, and 10-year follow-up, the UPROR rates were 6.6, 7.3, and 9.2%, respectively. Between 1997 and 2013, the UPROR rate decreased by 0.46% per year (95% CI 0.25-0.68, p < 0.001). Conclusion UPROR has decreased significantly over time but as expected, increases with increased follow-up.