Coverage of difficult wounds around the knee joint with prefabricated, distally based sartorius muscle flaps

The coverage of soft-tissue defects around the knee joint presents a difficult challenge to the reconstructive surgeon. Various reconstructive choices are available depending on the location, size, and depth of the defect relative to the knee joint. However, the knee joint frequently accompanies injuries to the lower leg that may limit the use of muscle flaps, especially the gastrocnemius muscle. The use of a free flap is preferred for reconstruction involving obliteration of large-cavity defects, but the isolation of recipient pedicle can be difficult because of the extent of injury zone and in cases of chronic infection around the knee. To provide muscle bulk with a reliable vascular supply, the distally based, prefabricated sartorius muscle flap was used as a last resort to reconstruct difficult wounds with chronic osteomyelitis around the knee joint in 6 patients from June 1995 to May 2001. This method is a two-stage procedure. First, the sartorius muscle is prefabricated by denervation and vascular delay. Silicone sheets are used to increase the vascularity and dimension of the flap. Second, after 3 weeks, the muscle is transposed based on a distal pedicle to reconstruct the soft-tissue defect around the knee. The prefabricated sartorius muscle can provide efficient bulk to obliterate the dead space and to cover moderate-size soft-tissue defects around the knee joint. This method can be considered to reconstruct the soft tissue around the knee joint when local muscle flaps and free flaps are not feasible.