Localized Development of Knee Osteoarthritis Can Be Predicted from MR Imaging Findings a Decade Earlier

Purpose: To define localized development of knee osteoarthritis (OA) that arises from anterior cruciate ligament (ACL) and meniscal injuries identified at magnetic resonance (MR) imaging performed a decade ago and the subsequent management of those findings in patients with subacute knee symptoms. Materials and Methods: The present study was approved by local medical ethics review boards, and written informed consent was obtained. Three hundred twenty-six patients (mean age, 42 years; 108 female) from a previously reported series of 855 patients were followed up with regard to the effect of MR imaging-guided treatment for subacute knee problems. The mean follow-up period was 10 years. Initial findings and treatment were compared with the follow-up radiograph and 3.0-T MR image findings. Odds ratios (ORs), with corresponding 95% confidence intervals, were used to identify the effects between variables. Results: Patients with ACL ruptures had an increased risk of developing joint space narrowing (JSN), cartilaginous defects, osteophytes, bone marrow lesions, and subchondral cysts medially or laterally (OR, 2.4-9.8). Patients with medial meniscal tears had an increased risk of developing JSN, cartilaginous defects, osteophytes, and bone marrow lesions medially (OR, 2.0-15.3). Patients with lateral meniscal tears had an increased risk of developing JSN, cartilaginous defects, osteophytes, bone marrow lesions, and subchondral cysts laterally (OR, 2.1-10.5). Meniscectomy had no effect on the risk of developing OA. Conclusion: Localized knee OA developed from risk factors identified from the findings of MR imaging performed a decade ago in patients with subacute knee symptoms and did not depend on the surgical treatment of those findings. (C) RSNA, 2010