| |
visualized. Flaps of up to 30 cm or more in length and 15 cm in width can be raised and closed primarily, without grafting. Flexion of the thigh and extensive undermining of the superior and inferior margins of the wound may be required to close this defect. A suction drain should be used and may drain fluid for many days. Occasionally, prolonged drainage is encountered, undoubtedly related to the transection of many lymphatics.
 B. The flap dissection is begun laterally. In slender individuals, it is often possible
to pick up the terminal cutaneous branches of T-12 entering the lateral portion of the flap,
converting this flap into a sensory cutaneous flap. In heavy individuals, this area is densely infiltrated with fat, and isolation of this cutaneous nerve is difficult. The nerve can usually be picked up about 3 to 5 cm below the posterior spine of the ilium, where it pierces the deep fascia of the lateral thigh. The nerve approaches the tip of the flap
in the subcutaneous fatty area. One should make every attempt to identify the fine cutaneous branches in between the fat lobules. One branch should be traced proximally to the junction of many other branches that join to form T-12 as it pierces the fascia. This fascia can be split for several centimeters and the nerve can be developed in a proximal direction to give greater length. Once this nerve has been isolated and cut, the flap can be elevated briskly to the anterior superior iliac spine (ASIS) without worry of injuring any key structures. One need not include the full thickness of the fat in the flank area because it is merely parasitic. The flap can be thinned down to the dermis in this area, if desired; however, if the nerve is carried with it, the tip of the flap naturally must be thicker.
|
|
 C. At the anterior spine, the groove between the tensor fascia lata and the sartorius muscle can be palpated and identified, and the lateral femoral cutaneous nerve of the thigh can be visualized as it pierces the deep fascia just below the spine. It is not unusual for a large cutaneous vessel to accompany this nerve. This vessel also communicates freely with the superficial circumflex iliac (SCI) vessels; sacrificing the nerve to preserve the blood
supply entering the flap may be necessary. Patients should be warned preoperatively about this area of numbness.
 D. The fascia over the sartorius muscle is incised over the lateral portion of the muscle and lifted with the flap to permit trapping of all cutaneous branches coming from the
iliac system. As one dissects across the sartorius muscle, one can usually visualize the superficial circumflex iliac vessels on the undersurface of the fascia, which can be confirmed with a sterile Doppler intraoperative probe. At the medial margin of the sartorius, a deeper branch pierces the fascia to enter the sartorius muscle. The fascia
next page... |
