Magnetic resonance imaging appearance of breaststroker's knee

Breaststroker's knee is an overuse syndrome resulting from similar repetitive movements in competitive swimmers that has been described in the orthopedic literature. The typical symptoms are medial knee pain with tenderness to palpation at the tibial collateral ligament or inferomedial patella. Despite these localizing symptoms on clinical exam, arthroscopic studies have failed to demonstrate a specific structural abnormality corresponding to this syndrome, although some have reported thickened medial synovial plica, medial-predominant synovitis or patellofemoral cartilage loss in association knee pain with breaststroke swimmers. We present a case of medial knee pain in a young breaststroke swimmer with magnetic resonance imaging (MRI) findings of marrow edema in the anterior aspect of the medial femoral condyle. To our knowledge, this is the first reported case of MRI findings in breaststroker's knee.