Synovial Lipomatosis in the Knee Joint: A Report of a Rare Condition

Synovial lipomatosis is an uncommon, benign intra-articular lesion that resembles a lipoma and typically affects the synovial lining of the knee joint. It can cause swelling and pain in the joint, as well as restrict movement. Mature fat, proliferating and infiltrating the hypertrophic synovial villi, primarily causes the lesion. Although the hip, glenohumeral, wrist, and ankle joints have also been reported to be affected, the knee joint is a common site of the condition. This benign condition has an unknown cause. This case report describes a 47-year-old male with right knee pain, swelling, and mechanical symptoms. Treatment options include conservative or surgical treatment, depending on the patient's symptom severity. In this case, we opted for surgical management, which included arthroscopic debridement and synovectomy. The occurrence of synovial lipomatosis in the knee is rare, so the treating surgeon must maintain a high level of suspicion.