Presentation
Left knee pain.
Patient Data
Marked left knee osteoarthritis, seen as subarticular sclerosis, narrowed tibiofemoral articulation distance and marginal osteophytes. Subchondral rounded lucencies are seen at the femoral and tibial aspects of knee joint, suggestive of subchondral bone cystic changes (geodes).
Arrows point to subarticular rounded lucencies, suggestive of subchondral bone cystic changes (geodes).
Case Discussion
Plain radiograph shows features of advanced knee joint osteoarthritis. There are well-defined lucencies that refer to subchondral cysts (geodes). Causes can be osteoarthritis, rheumatoid arthritis, amyloid arthropathy and osteonecrosis. Differential diagnoses are lytic epiphyseal lesions like chondroblastoma, metastasis and others.