A 59-year-old woman, had a left femoral venous thrombosis during a pregnancy 30 year ago. Her left greater saphenous vein had been stripped at age 21. She now presents with a large non healing ulceration over the medial left calf, which has continuously progressed despite bed rest, elevation, and use of a suppo stocking. Descending phlebography of the left leg demonstrates a patent deep venous system, with free flow of dye from the groin to foot. The first profunda femoris valve is competent. Appropriate management might include which of the following: