Read Aloud the Text Content

This audio was created by Woord's Text to Speech service by content creators from all around the world.

Text Content or SSML code:

This video provides a step-by-step instruction on how to harvest the pedicled superficial inferior epigastric artery fascia (SIEF) flap to wrap it around the nerve in a rabbit peroneal nerve defect model; a validated method to revascularize nerve grafts and enhance nerve regeneration. The SIEF flap is a pedicled flap supplied by superficial inferior epigastric vessels, including both the arteries and the accompanying veins. The vessels arise from the femoral vessels in proximity of branches of the popliteal and saphenous vessels, distal from the inguinal ligament. The main trunk divides into two branches. The main lateral trunk enters the abdominal wall skin, after branching off the femoral vessels in the groin. The smaller medial branch collaterizes with the internal mammary vessel as it extends towards the medical abdominal skin. Place the rabbit on his side and prepare it for sterile surgery. Ensure the leg can be maneuvered during the surgery. First the surgical approach to the peroneal nerve. Create a 10 cm incision in the skin of the posterolateral side of the thigh parallel to the femur. In order to expose the peroneal nerve branch of the sciatic nerve, separate the biceps femoris muscle from the gluteus maximus and vastus lateralis muscle by dissecting the fascia plane between these muscles. Use a retractor to visualize and perform a blunt dissection to expose the nerve layer by layer. Ensure the fascia is released over the entire length of the nerve to create enough room for the flap. Reposition the retractor to maximize the access to the nerve when needed. Carefully, Separate the nerve from the surrounding connective tissue. Ligate the caudal femoral artery and vein for better mobility of the nerve. If necessary, place a microsurgery background sheath under the nerve for better visibility. Carefully isolate the common peroneal nerve branch of the sciatic nerve. This is usually the most ventral branch. If necessary, you can further isolate the branch under the microscope. The nerve site is prepared for reconstruction after raising of the adipofascial flap. Temporarily approximate the skin. After continue to the surgical approach to the adipofascial flap, place the rabbit in a supine position. Create a superficial 10 to 14 cm paramedian incision in the epidermis starting under the xyphoid, medial to the nipple line. Bluntly dissect the fascia from the skin and release the incision step by step to avoid harming the fascia. Ligate Place single 4-0 nylon sutures in the epidermis along each side of the incision with mosquito forceps on each suture, to delicately maneuver the skin whilst separating the skin from the subcutaneous tissues. Separate the skin from the fascia to ensure plenty of room to dissect the 14 x 10 cm flap in the ventral abdomen. Ligate small epidermal perforating branches using the bipolar as needed. Take care to avoid damage to the pedicle whilst separating the skin from the fascia. If needed, retract the skin using a retractor with four prongs to maximize visibility. Dissect the flap starting on the medial side, lateral from the linea alba, in a cephalad direction. Elevate the fascia whilst dissecting, to avoid harming the abdominal muscles. Separate the superficial- and deep membranous layers of subcutaneous tissue (Camper fascia and Scarpa fascia) from the abdominal muscles, leaving the fascia intact Anticoagulate small vessel branches using a bipolar as needed to prevent postoperative hematomas. Next continue to the transverse dissection. Further separate the skin from the fascia where needed to create more room for the dissection. Ligate the pedicle as cranial as possible. Next continue to the lateral dissection to completely elevate the flap. Raise the flap towards the level of the bifurcation of the femoral artery in both planes, taking care not to damage the SIE vessels. Tunnel the flap towards the nerve reconstruction site, Bluntly dissect a wide subcutaneous tunnel into the inguinal region, above the fascia layer. Widen the tunnel from both sides to ensure the flap will not be constricted. pass the flap through the tunnel, such that the flap is rotated approximately 100 degrees clockwise about its axis and the vessels are kept ventrally. Ensure there is no pedicle torsion or compression in the subcutaneous tunnel. After approximating the abdominal incision in layers, the nerve reconstruction site will be prepared for repositioning of the flap. Here you can appreciate the length and width of the flap, as well as the bleeding of the pedicle. Re-expose the peroneal nerve reconstruction site. Reposition the flap around the retractor. Ensure there is no compression of the flap. Elevate the nerve with a vessel loop to reposition the flap under the nerve. Ensure there is enough length of the flap to cover both anastomoses without compressing the nerve or the pedicle, with full mobility of the leg. Next, the nerve reconstruction. Reposition the microsurgery background sheath. Further separate the peroneal nerve branch if necessary. 6 cm distal to the border of the external obturator muscle, excise a 25-mm segment of the peroneal nerve by sharp transection. Reconstruct the defect with a 30 mm nerve graft, using 10-0 nylon epineural sutures on either side of anastomosis. Loosely wrap the SIEF flap around the nerve with the pedicle vessels in line with the nerve, covering the proximal and distal anastomoses, without tension on the nerve. Trim the edges as needed. Loosely place 2 4-0 absorbable sutures through the edges of the flap to secure it around the anastomoses. Approximate the hindlimb incision in layers. After watching this video, you should have a good understanding how to replicate the surgical approach for vascularizing nerve grafts using the SIEF flap in a rabbit peroneal nerve defect model.