Fractional lengthening of hamstrings. A, Skin incision and incision in deep fascia over back of knee. B and C, Incisions in semimembranosus. D, Incisions in biceps femoris; note hemostat anterior to peroneal nerve. E, Tendon sheaths of biceps femoris and semimembranosus are sutured before wound closure. SEE TECHNIQUE 33.8.