The anatomical basis and clinical applications of the medial genicular artery flap, which is supplied mainly by the cutaneous perforator of the superior medial genicular artery, are herein described. Based on 10 cadaver dissections, the nutrient artery was found to be consistent and was seen to penetrate the deep fascia within a small triangular area bordered by the medial femoral condyle, the vastus medialis, and the adductor magnus tendon. The distal end of the flap must cover the skin over the medial femoral condyle, and the axis of the flap is along the lower half of the sartorius. The proximal end of the flap can be extended safely beyond the midpoint of the thigh. The medial genicular artery flap is thin and can nicely recontour defects around the knee, with an inconspicuous donor site on the medial aspect of the thigh.