Variants of hemipelvectomy.

Anterior flap hemipelvectomy is used for large, fixed tumors in the area of the buttock. The anterior flap consists of skin, subcutaneous fat, fascia lata, and the mobilized femoral vessels attached to the flap. It is accomplished by dividing the profunda femoris vessels. In routine posterior flap hemipelvectomy, a long flap can be constructed, if necessary, reaching to the level of the umbilicus. The viability of the posterior flap is assured by leaving the gluteus maximus muscle attached to it.