Tiam Mana Saffari

58 CHAPTER 3 raised to the level of the bifurcation of the femoral artery and then kept moist in gauze until the nerve reconstruction was finished. The sciatic nerve was fully exposed proximally from the inferior margin of the piriformis muscle to approximately 5 mm distal to the bifurcation, under an operating microscope (Zeiss OpMi 6, Carl Zeiss Surgica, Oberkochen, Germany). A 10-mm segment of the sciatic nerve was excised by sharp transection with microsurgical scissors and bridged with a 10-mm nerve allograft with six 10-0 nylon (10-0 Ethilon, Ethicon Inc., Sommerville, NJ, USA), epineural interrupted sutures on either side of anastomosis. A 2 cm linear incision was made from the patella toward the pelvis to develop a wide subcutaneous tunnel from the distal aspect of the nerve reconstruction toward the femoral artery. A hemostat was passed through the distal incision into the inguinal region, and the flap was delivered through the tunnel, with approximate 100° rotation clockwise about its original axis (Figure 4). Caution was taken to prevent vascular twisting. The 4 x 3 cm SIEF flap contained subcutaneous fat, inguinal fat, femoral vasculature and SIE vessels and was tunneled subcutaneously toward the nerve reconstruction without torsion of the pedicle (Figure 5A). Figure 4. Schematic drawing of flap rotation (A) and tunneling (B). The vessels were kept ventrally and the flap was tunneled without vascular twisting of the epigastric trunk. With permission of the Mayo Foundation, Copyright Mayo Foundation 2019. The flap was wrapped around the nerve allograft with the SIE vessels in line with the nerve and reaching both the proximal and distal anastomoses, as shown in Figure