Chen EY, et al. - Since some patients may develop a pattern of chronic opioid use [defined as having two or more opioid prescriptions filled within any six-week period] after total joint arthroplasty (TJA) due to the addictive property of opioid medications, researchers analyzed chronic prescription opioid use before and after total hip and knee arthroplasty in patients less than 65 years old. To identify 125,019 subjects (age < 65 years) who had total knee arthroplasty (TKA) and total hip arthroplasty (THA) between 2009 and 2012, MarketScan Commercial Claims and Encounters database were used. Using the chronic use definition, overall chronic opioid use fell from 19% to 9% after TJA. Following TJA, patients were more likely to cease using chronic opioids (72%) than to become chronic users (4%). TKA and hospital stay longer than 3 days were major risk factors for persistent chronic opioid use after surgery, while age played a mixed role in predicting changes in opioid use.