Lipoma Arborescens of the Knee: An Intraoperative Mimicker of Pigmented Villonodular Synovitis in Bilateral Knee Osteoarthritis - A Case Report.

INTRODUCTION

Lipoma arborescens (LA) is a rare benign synovial lesion characterised by villous fatty proliferation. Intraoperatively, it may mimic pigmented villonodular synovitis (PVNS) due to a similar frond-like, vascular synovial appearance.

CASE REPORT: We report a 74-year-old male with bilateral grade 4 knee osteoarthritis who underwent total knee arthroplasty. Diffuse villous synovial tissue was encountered intraoperatively, with unexpected bleeding despite tourniquet use. Histopathology confirmed LA. Intra-articular administration of tranexamic acid effectively controlled the bleeding.

CONCLUSION

The clinical outcome is favorable in most cases, unlike with PVNS.