Body Mass Index as a Risk Factor for 30-Day Postoperative Complications in Knee, Hip, and Shoulder Arthroscopy

Purpose: To use the American College of Surgeons National Surgical Quality Improvement Program database to determine whether body mass index (BMI) is associated with 30-day postoperative complications following arthroscopic surgery. Methods: Cases of elective knee, hip, and shoulder arthroscopy were identified. A retrospective comparative analysis was conducted, and the overall rates of morbidity, mortality, readmission, reoperation, and veno-thromboembolism (VTE) were compared using univariate analyses and binary logistic regressions to ascertain the adjusted effect of BMI, with and without diabetes, on morbidity, readmission, reoperation, and VTE. Results: There were 141,335 patients who met the criteria. The most common complications were deep vein thrombosis (0.27%), superficial surgical site infection (0.17%), urinary tract infection (0.13%), and pulmonary embolism (0.11%). Obesity class III with diabetes was a risk factor for morbidity (odds ratio [OR] = 1.522; 95% confidence interval [CI], 1.101-2.103) and readmission (OR = 2.342; 95% CI, 1.998-2.745) following all procedures, while obesity class I was protective toward reoperation (OR = 0.687, 95% CI, 0.485-0.973). Underweight patients were at higher risk for morbidity following shoulder arthroscopy (OR = 3.776; 95% CI, 1.605-8.883), as were the class I obese (OR = 1.421; 95% CI, 1.010-1.998) and class II obese (OR = 1.726, 95% CI, 1.159-2.569). BMI did not significantly affect morbidity following knee arthroscopy. VTE risk factors included being overweight (OR = 1.474; 95% CI, 1.088-1.996) or diabetic with class I obesity (OR = 1.469; 95% CI, 1.027-2.101). Conclusions: Arthroscopic procedures are safe with very low complication rates. However, underweight and class I and class II obese patients are at higher risk for morbidity following shoulder arthroscopy, and diabetic patients with class III obesity are at higher risk for morbidity and readmission following all arthroscopy. Because BMI is a modifiable risk factor, these patients should be evaluated carefully before being considered for outpatient arthroscopic surgery.