P35. Clinical outcome of surgical site infection after spinal fusion

Abstract

<h3>BACKGROUND CONTEXT</h3> Surgical site infections (SSIs) pose a significant burden to both patients and the health care system with recent focus on the identification and modification of applicable risk factors in spine surgery. However, there is a paucity of literature evaluating the clinical outcomes of patients treated for infection after spine surgery. <h3>PURPOSE</h3> To compare the clinical outcomes of patients who developed SSI after thoracolumbar spine surgery to an aseptic control cohort. <h3>STUDY DESIGN/SETTING</h3> Retrospective propensity matched case-control study. <h3>PATIENT SAMPLE</h3> Adult patients who underwent thoracolumbar spinal fusion between March 2014 and January 2020. <h3>OUTCOME MEASURES</h3> Oswestry Disability Index (ODI), Visual Analog Scale (VAS) Back and Leg, Physical Component (PCS) and Mental Component (MCS) of the SF-12. <h3>METHODS</h3> Structured query language query (SQL) was used to identify patients and extract patient-reported outcome measures (PROMs). Demographic data was extracted through chart review. Patients who developed an SSI were matched to a control cohort based on age, sex, body mass index (BMI), diabetes status, smoking status and race through propensity score matching. <h3>RESULTS</h3> A total of 176 patients (132 Control, 44 SSI) with a mean age of 66 years, body-mass index of 34, ASA of 2.76 were included in final analysis. Both groups demonstrated significant improvements in ODI (Control: p<0.001, SSI: p=0.006), VAS Back (Control: p<0.001, SSI: p=0.002), VAS Leg (Control and SSI:p<0.001), and PCS-12 (Control:p<0.009, SSI:p=0.01) after surgery. Despite comparable preoperative and ∆ODI scores, patients who had an SSI had significantly worse postoperative ODI scores (Control:28.5, SSI: 37.5, p=0.024). ∆VAS Leg, ∆VAS Back, ∆PCS-12, and ∆MCS-12 did not differ significantly between groups with no difference in the proportion of individuals meeting MCID for VAS Leg (60.6% vs 57.1%, p=0.899), VAS Back (Control: 63.6%, SSI: 57.1%, p=0.667), PCS-12 (Control: 22.1%, SSI: 26.1%, p=0.868) or MCS-12 (Control: 20.5%, SSI: 30.4%, p=0.427). <h3>CONCLUSIONS</h3> Despite the associated morbidity of infection after spine surgery, the results of this study demonstrate that patients who sustain SSI after lumbar fusion can ultimately expect similar clinical outcomes as those without postoperative complications and can be used by surgeons to help counsel patients. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.