Gastrocnemius muscle transposition to the femur: how high can you go?

The gastrocnemius muscle flap has gained wide acceptance as a reconstructive technique for management of wounds of the knee and proximal tibia. The use of the muscle as a pedicle flap to the distal and middle femur has not been well quantified, and the proximal rotation arc has been underestimated. We report the use of the island gastrocnemius pedicle flap to reach two femur defects 21 and 26 cm above the joint line, achieved by taking advantage of the favorable location of the vascular pedicle above the joint line and the individual length of the medial gastrocnemius muscle belly. Evaluation of standard arteriograms suggests the location of the medial sural artery pedicle is an average of 32 +/- 14.5 (SD) mm above the inferior border of the femur. All vessel origins were found above the joint line by radiograph. A common sural artery origin was noted in 32% of patients at a mean distance of 35 mm proximal to the joint line. Despite a wide range, 62% of sural artery origins were within 1 cm of an axis drawn through the widest point of the femoral condyles.