Arthroscopic Fixation of an Atraumatic Osteochondral Defect of the Knee: A Case Report.

Introduction: Osteochondral defects cause significant loss of articular cartilage and subchondral bone, often leading to osteoarthritis if untreated. Early diagnosis and intervention are crucial to prevent degenerative joint disease. This case report documents the first successful use of arthroscopic reduction internal fixation for an atraumatic osteochondral defect in a young, healthy individual, demonstrating the potential of this minimally invasive approach. Case Report: A 27-year-old Hispanic male with no significant medical history presented with restricted left knee extension and occasional locking after recreational swimming. Physical examination showed tenderness along the knee borders, a positive varus stress test, and limited extension. Imaging studies identified a large, unstable osteochondral lesion in the lateral femoral condyle. Arthroscopy confirmed the defect, measuring approximately 4.5 cm × 1.5 cm, and fixation was performed using three headless compression screws. Post-operative recovery was smooth, with the patient regaining full functionality within 3 months and excellent outcomes at the 2-year follow-up visit. Conclusion: This case highlights the importance of considering osteochondral defects in young patients with knee pain, even without trauma. The successful use of ARIF for a large, atraumatic osteochondral defect demonstrates the efficacy of minimally invasive techniques in treating such lesions. We underline the importance of maintaining a high index of clinical suspicion for this diagnosis in young patients presenting with knee pain.