Spontaneous recurrent hemarthrosis of the knee joint in elderly patients with osteoarthritis: an infrequent presentation of synovial lipoma arborescens

Abstract

Synovial lipoma arborescens (SLA) is a rare, benign, fat-containing synovial proliferative lesion that is typically known to affect the knee joint in adults, although it has also been described in other joints. SLA usually presents as a painless swelling and recurrent joint effusion, and the laboratory test results, including aspirated synovial fluid, are usually normal. We present here two cases of SLA of the knee, which presented as spontaneous recurrent hemarthroses in elderly patients with osteoarthritis (OA) with bloody aspirated synovial fluid. Magnetic resonance imaging (MRI) and arthroscopic synovectomy suggested the diagnosis of SLA; the histopathologic examination confirmed the diagnosis. One year later, both patients remain symptom-free and report no new episodes of hemarthrosis. We postulate that SLA should be included in the differential diagnosis of patients with recurrent joint effusions with hemarthrosis in elderly patients with OA. The clinical presentation, MRI findings, and treatment of SLA are described, and the entity is briefly reviewed.

Bilateral Knee Lipoma Arborescens Combined with Osteoarthritis in Elderly Patients

“…16 Among the published cases of LA, bilateral knee LA and LA combined with OA were both infrequent. To our knowledge, only eight cases of pure bilateral knee LA 6 -9,16 -18 and three cases of unilateral knee LA combined with OA 9,19 have been reported. The combination of bilateral LA and OA was even more infrequent.…”

“…The aspirate is typically yellow, and haemarthrosis is rare. 19 These symptoms are somewhat similar to those of OA, and the findings at physical examination (such as reduced range of motion, a positive patella rubbing test and a negative floating patella test) are not pathognomonic of LA. Routine plain radiographs are insensitive to discern soft tissue masses 17 and lucent areas 6,20 within the suprapatellar pouch.…”

Lipoma Arborescens: Review of an Uncommon Cause for Swelling of the Knee

“…MRI demonstrates a lobulated intra-articular mass with a hyperintense signal due to pooling of blood in vascular spaces. Furthermore, lipoma arborescens usually arises in the suprapatellar pouch, whereas a synovial hemangioma is primarily found in the infrapatellar pad [ 22 , 28 ].…”

Lipoma arborescens of the knee joint

“…Though it occurs in the knee joint most commonly, it may also occur in other joints. LA presents with painless, slowly progressing swelling associated with intermittent joint effusions 2. MRI is the best modality to diagnose LA.…”