Background: The versatility of the gastrocnemius muscle for reconstruction of defects in the knee region from the upper third of the calf to the lower third of the thigh is well known. Possible limitations of this flap include difficulties in covering multiple separate wounds in the same area as well as contour deformity because of the flap bulkiness. The findings in this study extend the versatility of the gastrocnemius muscle flap by splitting each head into two segments allowing for the closure of multiple defects.
Methods: Studied was the vascular anatomy of 15 fresh cadaveric lower extremities. Contrast material was injected into the sural artery and this showed the bifurcation of the pedicle in the upper third of the muscle. A constant intramuscular vascular pattern represented by two main longitudinal branches permitted the safe division of each head. Based on these anatomic studies, segmentation was performed of the gastrocnemius muscle flap in 29 patients. In 13 cases were used, one or two muscle segments and in 16 cases, three muscle segments were transposed.
Results: All of the flaps survived. Minor complications, such as wound dehiscence, cellulitis, or hematoma, were encountered in seven patients. Except for one patient with persistent drainage from osteomyelitic bone, all the wounds closed successfully.
Conclusions: The authors report the safe splitting of the distal gastrocnemius muscle in 29 patients based on vascular anatomic studies. The advantages of gastrocnemius segmentation include the possibility of covering multiple defects with less contour deformity.