Pseudoaneurysm of the Medial Genicular Artery as a Rare Cause of Recurrent Knee Swelling - A Case Report.

Introduction: Recurrent knee swelling in elderly or anticoagulated patients is commonly attributed to conditions, such as deep vein thrombosis (DVT), Baker's cyst rupture, septic arthritis, or anticoagulation-related hemarthrosis. However, vascular causes, such as genicular artery pseudoaneurysm, are rare and may be overlooked, especially when symptoms persist despite appropriate treatment. Case Report: We describe a 60-year-old male with multiple comorbidities who presented with recurrent painful swelling of the right knee. Initial evaluations identified sequential pathologies, including popliteal DVT, ruptured Baker's cyst, and septic arthritis, all treated appropriately. Despite resolution of infection and withdrawal of anticoagulation, hemarthrosis recurred. Further evaluation with Doppler ultrasonography and magnetic resonance angiography revealed a pseudoaneurysm of the superior medial genicular artery. The lesion was successfully treated using ultrasound-guided compression, resulting in complete thrombosis and resolution of symptoms without complications. Conclusion: Superior medial genicular artery pseudoaneurysm is a rare but important cause of recurrent hemarthrosis. Persistent or unexplained knee swelling should prompt early vascular imaging to avoid diagnostic delay and enable timely, minimally invasive management.