Summary

Utilizing a national surgical database, this study confirms the 30-day overall complication (1.75%) and readmission rates (0.92%) are low for knee arthroscopy procedures, however age>60, smoking status, recent weight loss, COPD, hypertension, diabetes, chronic steroid use, ASA class >2, and operative time >45 minutes are independent risk factors for readmission.

Abstract

Purpose

The purpose of this study is to evaluate knee arthroscopy cases in a national surgical database to identify risk factors associated with readmission following this routine orthopaedic procedure.

Methods

The American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database was queried from 2012 to 2016 for current procedural terminology (CPT) billing codes related to knee arthroscopy. International Classification of Diseases, Ninth and Tenth Editions (ICD-9 and ICD-10) diagnostic codes were then used to exclude cases which involved infection. Patients were subsequently reviewed for readmission within 30 days. Univariate and multivariate analyses were then performed to identify risk factors associated with 30-day readmission.

Results

We identified 69,022 patients who had undergone knee arthroscopy. The most common primary procedures were unilateral meniscectomies (n=39,663, 57.46%) and bilateral meniscectomies (n=13,618, 19.73%). The overall 30-day complication rate was 1.75% and the most common complications following the procedure were returning to the operating room (n=317, 0.46%), deep venous thrombosis (n=257, 0.37%), and superficial infections (n=148, 0.21%). The 30-day readmission rate was 0.92%. On multivariate analysis, age >60 (odds ratio [OR], 1.29; 95% confidence interval [CI], 1.07-1.55), smoking (OR, 1.40; 95% CI, 1.15-1.70), recent weight loss (OR, 13.22; 95%CI, 5.03-34.73), history of chronic obstructive pulmonary disease (COPD) (OR, 1.98; 95%CI, 1.39-2.82), hypertension requiring medication (OR, 1.48; 95%CI, 1.23-1.78), diabetes (OR, 1.92; 95%CI, 1.40-2.64), renal failure (OR, 10.65; 95% CI, 2.90-39.07), chronic corticosteroid or immunosuppressant use for a chronic condition within 30 days prior to the procedure (OR, 1.91; 95% CI, 1.24-2.94), American Society of Anesthesiologists (ASA) class >2 (OR, 1.69; 95% CI 1.40-2.04), and operative time >45 minutes (OR, 1.68; 95% CI 1.42-2.00) were identified as independent risk factors for readmission. The mean operative time for those patients requiring readmission and not requiring readmission was 48.4 and 41.7 minutes, respectively.

Conclusion

These findings confirm that the 30-day overall complication (1.75%) and readmission rates (0.92%) are low for knee arthroscopy procedures, however age>60, smoking status, recent weight loss, COPD, hypertension, diabetes, chronic steroid use, ASA class >2, and operative time >45 minutes are independent risk factors for readmission.