Silva GS, Sullivan JK, Katz JN, et al. - Researchers developed parameters that would make a short-term (3-year efficacy) physical activity (PA) program a cost-effective component of long-term osteoarthritis (OA) care. They applied a validated computer microsimulation (Osteoarthritis Policy Model) to analyze the long-term clinical (eg, comorbidities averted), quality of life (QoL), and economic impacts of a 3-year PA program, based upon the Studying Physical Activity Rewards after Knee Surgery (SPARKS) Trial, for inactive knee OA patients. They ascertained the cost, efficacy, and effect of PA on QoL and medical costs that would make a PA program a cost-effective addition to OA care. In the knee OA population, a PA program with 3-year efficacy carried favorable long-term clinical and economic advantages. These favorable outcomes may help support policymakers and payers considering a PA intervention incorporated into knee OA care.