The medial superior genicular artery is a branch of the popliteal artery. It runs in front of two of the hamstring muscles, the semimembranosus and semitendinosus. It runs underneath the tendon of a third hamstring muscle, the adductor magnus. It and its branches supply the teardrop muscle (vastus medialis), the femur, and the knee-joint with oxygenated blood. The artery and its branches merge (anastomosis) with the lateral superior genicular artery, the medial inferior genicular artery, and the highest genicular artery.
One complication of knee replacement surgery is a pseudoaneurism of the medial superior genicular artery. One case reported in the medical literature is of a woman who experienced a lesion on her knee six weeks after arthroplastic surgery that was suggestive of a haematoma. Ultrasonography indicated a mass a little more than 1 centimeter in its height, width, and breadth on the medial superior genicular artery. The cystic lesion was diagnosed as a pseudoaneurism.
Administration of warfarin was stopped, and a compression dressing was applied. Five days later, angiography was showing no evidence of the pseudoaneurism in the medial superior genicular artery.