INTRODUCTIONMeniscal tears are highly prevalent, with imaging evidence of a meniscal tear observed in 35% of persons older than 50 years of age; two thirds of these tears are asymptomatic.1,2 Meniscal damage is especially prevalent among persons with osteoarthritis and is frequently treated surgically with arthroscopic partial menisectomy. 3,4 The high prevalence of meniscal tears in patients with osteoarthritis of the knee and the observation that these lesions are often asymptomatic, challenge the ability of clinicians to determine whether symptoms are caused by the tear, osteoarthritis, or both.The role of arthroscopic surgery in patients with osteoarthritis has been studied over the past decade. Studies have not shown a statistically significant or clinically important difference between the arthroscopic and non-operative groups with respect to functional improvement or pain relief over a follow upperiod.1,2 However, they did not focus on management of a symptomatic meniscal tear, which is a frequent indication for knee arthroscopy in patients with osteoarthritis of the knee. Therefore, we conducted this trial to assess the efficacy of arthroscopic partial meniscectomy as compared with a standardized physical-therapy regimen ABSTRACT Background: In patients with a meniscal tear and mild-to moderate osteoarthritis, we analyzed whether arthroscopic partial meniscectomy improve physical and functional outcomes more than physical therapy does. Methods: 52 patients had a meniscal tear as well as osteoarthritis confirmed by magnetic resonance imaging or radiography. Symptoms had persisted for more than 3 months despite conservative measures. Patients were allocated to Group A subjected to partial meniscectomy and postoperative physical therapy (n=26) or to Group B with physical therapy alone (n=26). The primary outcome measure was change on the physical-function scale of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) during the 6 months after randomization. A 12-month assessment was added to determine the stability of the result. Secondary outcomes were the pain score on the Knee Injury and Osteoarthritis Outcome Score (KOOS). Results: At 6 months, the 2 groups did not differ in mean improvement in the WOMAC physical-function score, in decreases on the KOOS pain score. The results were similar at 12 months. Conclusions: In patients with a meniscal tear and mild-tomoderate osteoarthritis, both groups showed similar outcomes between arthroscopic meniscectomy and physical therapy.