179. Propensity-matched analysis of 1,062 patients following minimally invasive versus open sacroiliac joint fusion

Abstract

BACKGROUND CONTEXT The sacroiliac joint (SIJ) has been identified as a primary pain generator in a considerate proportion of low back pain (LBP) patients. Many patients turn to SIJ fusion after failure of conservative care to relieve SIJ pain. There are two surgical options for fusing the SIJ; an open or minimally invasive (MIS) approach. The open approach typically results in higher rates of postoperative complications and less improvement in patient reported pain and disability scores. PURPOSE The purpose of this study was to analyze the associated costs and postoperative complications of MIS and open approaches to SIJ fusion. STUDY DESIGN/SETTING Propensity-matched retrospective cohort study using the 2016-2017 National Readmission Database. PATIENT SAMPLE After excluding for all patients who had a prior SIJ fusion, those diagnosed with prior neoplasms or trauma of the pelvis and/or sacrum, and individuals whose primary SIJ fusion was nonelective, we identified 2,521 patients who received a SIJ fusion with an open (n=1,990) or MIS approach (n=531) for diagnosed sacrum pain, sacroiliitis, sacral instability or spondylosis. We then one-to-one propensity-matched the open (n=531) to the MIS approach (n=531) for age, sex and Charlson Comorbidity Index (CCI). OUTCOME MEASURES Costs, surgical outcomes, non-elective readmission rate, 30-, 90- and 180-day postoperative complications. METHODS We collected all of the individuals that had a non-elective readmission, separated them by surgical approach, and analyzed associated costs, surgical outcomes, non-elective readmission rate, 30-, 90- and 180-day postoperative complications. Statistical analysis was conducted in RStudio, with Welch two sample t-tests to compare complications and costs by surgical approach. RESULTS The mean cost of open SIJ fusion and was significantly higher compared to the MIS group (open $101,061.90 ±$81,136.67; MIS $83,594.78 ± $49,086.00, p CONCLUSIONS The current study found that MIS SIJ fusion was significantly less expensive than open SIJ fusion and was associated with less costly readmissions. Although no significant differences in postoperative outcomes were found, there were several notable trends specific to each surgical approach. Further investigation is required to fully characterize the potential advantages and disadvantages of the two surgical approaches. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.