DOI: https://doi.org/10.36347/sjmcr.2026.v14i05.073

Pages: 1175-1178

Differentiating Osteochondritis Dissecans (OCD) from Subchondral Insufficiency Fracture of the Knee is essential due to differences in pathophysiology, prognosis, and management [1–3]. We report two cases across different age groups highlighting the key role of MRI in this distinction. An 18-year-old patient presented with knee pain, instability, and mechanical symptoms. MRI revealed an osteochondral lesion of the medial femoral condyle with a T2 hyperintense fluid interface at the fragment–bone junction and subchondral bone marrow edema, consistent with unstable OCD (Hefti stage III). An elderly patient presented with acute-on-chronic knee pain without trauma. MRI demonstrated a linear hypointense subchondral fracture line with extensive bone marrow edema, without osteochondral fragment or fluid interface, consistent with SIFK. These cases emphasize that MRI enables reliable differentiation between OCD and SIFK based on fragment integrity, fluid interface, and fracture morphology, which is essential for appropriate management and prognosis.