Limb-sparing surgery for bony tumors around the knee, resulting in large segmental defects, involves its replace- ment with an endoprosthesis. The viability of the overlying skin flaps is of utmost importance. Their healing with- out breakdown is essential or else leads to prosthesis exposure, infection and perhaps prosthesis removal. In this situation, gastrocnemius muscle transfer is a robust vascular option, not only providing soft padding to cover the endoprosthesis, but also supporting the vascularity of the skin flaps. Out of 16 such muscle transfers done, 15 survived completely with good wound healing. One patient developed a severe infection of the wound associated with skin flap breakdown and necrosis of part of the muscle flap. There was 1 case of wound haema- toma which was treated successfully.

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