MATERIAL and METHODS: The American College of Surgeons National Surgical Quality Improvement Program database (2012? 2014) was reviewed. We included adult patients who underwent 3CO and compared pertinent cases (SSI) to controls (no SSI) in terms of preoperative and operative characteristics. Patients with clean/contaminated, contaminated, and dirty/infected wounds were excluded. A stepwise multivariate regression was used to identify independent predictors of SSI, with results presented as odds ratios (OR) with 95% confidence intervals (CI).

RESULTS: There were 293 patients who underwent 3CO for spinal deformity, out of whom 15 (5.1%) developed a SSI during the 30- day follow-up period. Of the 15 patients with SSI, 10 underwent reoperation (66.7%) within 30 days. Compared to controls, patients in the SSI group were more likely to be obese (p=0.030), have a higher American Society of Anesthesiologists (ASA) physical status class (p=0.051) and be more likely to undergo multilevel 3CO (p=0.013). After controlling for obesity, bleeding disorder, deformity type, ASA class, preoperative anemia, and multilevel procedures, Class II obesity (OR 4.98; 95% CI, 1.24 ? 19.94; p=0.023) and multilevel 3CO (OR 4.71; 95% CI, 1.30 ? 16.94; p=0.018) were significant predictors of SSI occurrence.

CONCLUSION: Patients with Class II obesity and patients who undergo multilevel osteotomy may be at a significantly increased risk of developing a SSI within 30 days after 3CO for spine deformity. Keywords : National Surgical Quality Improvement Program, Spinal deformity, Surgical site infection, Three-column osteotomy