Abstract Lipoma arborescens (LA) is a rare intra-articular lesion characterized by diffuse villous lipomatous proliferation of the synovium. While it predominantly affects the knee, it is often misdiagnosed due to its nonspecific presentation and overlapping features with other synovial disorders. Given its rarity, particularly in young adults, this case report highlights the importance of early recognition and appropriate management to prevent long-term joint damage. The present case is distinctive due to the unusually young age of the patient, the 6-year untreated duration, and significantly elevated inflammatory markers, all of which created a diagnostic challenge not commonly described in previous literature. A 23-year-old male presented with a 6-year history of progressive knee swelling and pain. He had undergone multiple aspirations at another center with no lasting relief. Examination revealed a diffuse swelling over the anteromedial knee with tenderness and restricted motion (0°–90°). Imaging demonstrated joint effusion, nodular synovial thickening, and fat proliferation, raising suspicion for LA. Histopathological findings confirmed the diagnosis, showing mature adipocytes with characteristic “tree-like” projections within the synovium. The patient underwent arthroscopic synovectomy using an aggressive shaver and radiofrequency ablation, resulting in significant symptom improvement. Postoperative rehabilitation was initiated to restore joint function and mobility. This case underscores the importance of considering LA in young patients with chronic knee swelling and recurrent effusions. Magnetic resonance imaging remains the diagnostic modality of choice, and arthroscopic synovectomy with adjunctive radiofrequency ablation offers an effective treatment approach. Timely intervention is crucial to prevent secondary osteoarthritis and functional impairment. This case adds to the orthopedic literature by emphasizing advanced imaging and minimally invasive surgical techniques in the management of this rare condition.
Rawal et al. (Wed,) studied this question.