Factors That Increase the Risk of Infection After Elbow Arthroscopy: Analysis of Patient Demographics, Medical Comorbidities, and Steroid Injections in 2,704 Medicare Patients

Abstract

To use a national database to determine (1) the incidence of joint infection after elbow arthroscopy, (2) identify independent patient-related risk factors for infection, and (3) determine the influence of concomitant intra-articular corticosteroid injection on infection risk. The 100% Medicare Standard Analytic Files were queried to identify patients who underwent elbow arthroscopy from 2005 to 2012. Postoperative elbow infections occurring within 6months of surgery were identified using both International Classification of Diseases, 9th Revision codes for postoperative infection and Current Procedural Terminology codes for the surgical treatment of a postoperative infection. Patients were excluded if their initial arthroscopic procedure was performed for infection. A multivariate binomial logistic regression analysis was then used to evaluate patient-related risk factors for postoperative infection. Of the 2,704 elbow arthroscopy cases identified, 42 (1.55%) developed a postoperative infection. The annual incidence of infections did not increase significantly over the course of the study (P= .374). A number of patient demographics and medical comorbidities significantly increased the risk of infection. The most notable factors included age ≥ 65years (odds ratio [OR] 2.38, P= .006), body mass index > 40 (OR 1.97, P= .024), tobacco usage (OR 1.80, P= .046), alcohol usage (OR 4.01, P < .001), diabetes mellitus (OR 2.10, P= .015), inflammatory arthritis (OR 2.81, P < .001), hypercoagulable disorder (OR 2.51, P= .015), and intra-articular corticosteroid injection at the time of arthroscopy (OR 2.79, P= .006). The annual number of elbow arthroscopies performed in the United States has increased steadily; however, the postoperative infection rate remained consistently low at 1.55%. There are a number of patient-specific risk factors that increase this risk with OR ranging from 1.97 to 4.01. Similarly, patients who receive an intra-articular corticosteroid injection at the time of surgery are nearly 3 times (OR 2.79) more likely to develop a postoperative infection. LEVELOFEVIDENCE: Level III, case-control study.