A Case of Fixation Using Poly-L-Lactic Acid Pins for Chronic Juvenile Massive Osteochondritis Dissecans of the Knee

Introduction: Chronic juvenile massive osteochondritis dissecans (OCD) presents significant therapeutic challenges due to the lack of established treatments. We herein report a case of chronic juvenile massive OCD treated with poly-L-lactic acid pin fixation. Case Report: A 13-year-old boy presented to another hospital with right knee pain after playing football. Initially, no significant abnormalities were noted, and he was placed under observation. However, the pain later worsened, and he was referred to our hospital with a diagnosis of OCD. An X-ray revealed a defect posterior to the lateral femoral condyle and a loose body in the suprapatellar bursa. Magnetic resonance imaging indicated the presence of a lateral discoid meniscus. Three months after the onset of symptoms, osteochondral fragment fixation and saucerization of the lateral meniscus were performed. One year postoperatively, the patient showed a good outcome with no recurrence of symptoms. Conclusion: Chronic juvenile massive OCD may achieve fusion with fixation, even when bone fragments consist only of cartilage. Keywords: Juvenile, knee, osteochondritis dissecans, poly-L-lactic acid pin.