You are in: eMedicine Specialties > Plastic Surgery > TRUNK Perineal ReconstructionArticle Last Updated: Jun 18, 2006AUTHOR AND EDITOR INFORMATIONSection 1 of 10
  Author: Chet L Nastala, MD, Plastic, Reconstructive, and Microsurgical Associates of South Texas, PA Editors: Dennis P Orgill, MD, PhD, Associate Professor, Harvard Medical School; Director, Burn Center, Brigham and Women's Hospital; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Jaime R Garza, MD, DDS, FACS, Consulting Staff, Private Practice; Nicolas (Nick) G Slenkovich, MD, Practice Director, Colorado Plastic Surgery Center at Swedish Medical Center; Jorge I de la Torre, MD, FACS, Professor of Surgery and Physical Medicine and Rehabilitation, Residency Program Director, Division of Plastic Surgery, University of Alabama at Birmingham; Director, Center for Advanced Surgical Aesthetics Author and Editor Disclosure Synonyms and related keywords: perineal reconstruction, genitourinary reconstruction, rectal cancer reconstruction, urogenital reconstruction, perineal defect, pelvic tumor, pelvic irradiation INTRODUCTIONSection 2 of 10
  Perineal reconstruction may be divided into genitourinary reconstruction for acquired and congenital deformities and reconstruction for cancer. Reconstruction for congenital deformities is covered under the topic of urogenital reconstruction, while penile and vaginal reconstructions are covered separately in this journal. This article discusses perineal reconstruction related to cancer ablation in both male and female patients. The plastic surgeon encounters large defects in the perineal region most commonly in male patients following ablation of a recurrent low pelvic tumor. This is observed most often in concert with extensive irradiation of the pelvis. Preoperative consultation with the plastic surgeon is sought most often when the ablative surgeon is not confident that he or she can achieve a closed wound primarily. The oncologic team principally is concerned with separating the pelvic and abdominal cavities, protecting the small bowel from postoperative enteritis problems, preventing postoperative perineal herniation, and obtaining a healed wound primarily. Because this anatomic site is particularly prone to wound healing problems, the cancer surgeon often is concerned with bringing fresh, nonirradiated, vascularized tissue into the region. ClinicalPerform an overall nutritional assessment, including serum parameters, to determine the patient's suitability for large flap procedure. Assess the degree and nature of the expected perineal wound following cancer ablation; this can be performed most accurately in consultation with the cancer surgeon. In the female patient, this involves anticipated defect of the external genitalia, labia, minora, and majora; the extent of the perineal skin defect; and the extent of total or partial vaginectomy planned. If partial or total perineal proctectomy is performed with the surrounding skin, assess how much skin to remove. If cystectomy is planned or is possible, preoperative involvement of a urologist for planning ileal conduit is essential. INDICATIONSSection 3 of 10
Perineal reconstruction is indicated when the anticipated defect is large and cannot be enclosed primarily. The following flaps may be considered in the preoperative evaluation of the patient:
These flaps represent a partial, though not exhaustive, list of those that should be considered preoperatively. Assess whether stomas are to be created through the remaining rectus muscle and whether sacrifice may be contraindicated. Certain flaps may be favored because of positioning considerations; for example, the split gluteus myocutaneous flap can be performed with the patient in the prone position. If the defect is limited to the perianal region, these flaps are robust and may provide adequate closure. If the defect is anticipated to be superficial only, then a groin flap, pudendal flap, or posterior thigh flap may be preferred. If significant dead space requires obliteration, a rectus abdominus myocutaneous flap based vertically (VRAM) or horizontally (TRAM) may be indicated. Lower extremity flaps (eg, tensor fascia lata, vastus lateralis, rectus femoris) may be preferred if abdominal or other donor sites are unavailable. In addition, a variety of other flaps are used less commonly but may be indicated in specific instances. These include the internal oblique muscle flap, omentum, medial or anterior thigh flaps, or superficial inferior epigastric artery flap. The gracilis flap represents the "workhorse" for reconstruction of the perineal and pelvic defect. In 1976, McCraw et al described the original reconstruction with the gracilis myocutaneous flap. RELEVANT ANATOMYSection 4 of 10
The major blood supply to the gracilis myocutaneous or gracilis muscle flap is derived from the medial femoral circumflex artery. This artery enters the muscle approximately 8-10 cm below the inguinal ligament. Additional minor perforators originate proximally from the obturator artery and may supply a short gracilis flap. Occasionally one or two branches from the superficial femoral artery supplying the middle and distal portions of the muscle may be divided. The nerve supply is the anterior branch of the obturator nerve, located between the adductor longus and magnus muscles. This nerve enters from deep to superficial, 1-2 cm superior to the major vascular pedicle from the medial femoral circumflex. When the adductor longus and magnus are retracted and the pedicle is dissected to the profundus femoris artery, its length ranges from 5-7 cm. This allows for more proximal positioning of the muscle pedicle. The overlying skin paddle of the medial thigh may be elevated with the muscle. However, exercise care in elevating the skin territory distal on the medial thigh that has poor reliability. The skin island may be relocated more reliably proximally over the proximal two thirds of the muscle. Carefully elevate small musculocutaneous or septal perforators with the surrounding fascia over the sartorius laterally and the adductors medially to capture both the musculocutaneous perforators through the gracilis muscle as well as small septocutaneous perforators that may lie on either side of it. CONTRAINDICATIONSSection 5 of 10
Entertain the possibility of vascular disease in the lower extremity. Seek clinical assessment for claudication or other symptoms of vascular disease. Thorough examination of the peripheral pulses may indicate vascular disease, which may be a contraindication to gracilis reconstruction. TREATMENTSection 6 of 10
Preoperative DetailsObtain a full preoperative evaluation of the patient. This includes determination of the patient's history of the present illness with regard to status of the radiation dose and in particular, the radiation ports. Chronically indurated or erythematous tissue should be noted and potentially removed with ablation. Also explore chronic problems with fistula formation. Intraoperative DetailsGracilis FlapOperative technique
Rectus Abdominus FlapThe rectus abdominis flap, distally based in the deep inferior epigastric vessels, provides several distinct advantages over bilateral gracilis flap reconstruction. Its most obvious advantage is the robust skin paddle that can be de-epithelialized for bulk or tubed for neovaginal reconstruction. For large pelvic exenteration defects, the rectus abdominis muscle can be used alone or in combination with the de-epithelialized skin paddle. This flap is well perfused by the robust dominant pedicle and the deep inferior gastric artery and vein. In addition, this flap provides adequate muscle bulk to obliterate pelvic dead space. The skin island can be used for resurfacing the perineal region, including the vaginal wall, and provides versatility for all patterns of resection. Operative technique
Deep inferior epigastric perforator flapAlthough the deep inferior epigastric perforator (DIEP) flap has become well-established as an accepted technique for breast and trunk reconstruction, its use in the perineum as both a pedicled and free flap has become more common. An advantage of the DIEP flap over pedicled rectus myocutaneous techniques is significantly less abdominal wall morbidity. However, this advantage may be outweighed by some considerations. First, the technical difficulties in flap harvest must be overcome by the steep learning curve with difficulties in flap venous insufficiency and perforator injury. Second, limitations in flap design with the DIEP flap make its use in perineal reconstruction more challenging than pedicled vertical rectus techniques. Operative technique In summary, the DIEP flap is designed as a horizontal skin island extending from the umbilicus to the suprapubic crease. Harvest includes no rectus abdominus muscle but a large segment of lower abdominal wall subcutaneous tissue, the Scarpa fascia, and the fatty layer below the Scarpa fascia. Once the tissue is freed to the level of the deep inferior epigastric vessels, the flap may be transposed into the pelvis without free tissue transfer; care should be taken not to kink or place tension on the pedicle. Split Gluteus Maximus Myocutaneous FlapWhile many variations of gluteus maximus flaps have been described, the split gluteal flap is particularly useful in resurfacing pelvic defects. In this flap, only the superficial 1-1.5 cm of gluteal muscle is harvested, supplied by the proximal parasacral perforators. This allows elevation of the gluteal region primarily as a musculofascial cutaneous flap. Operative technique
Gluteal Thigh FlapThe gluteal thigh flap may provide a reliable, versatile reconstruction of perineal defects, with low donor site morbidity. This flap includes the inferior portion of the gluteus maximus muscle and encompasses the territory of the posterior thigh, directly supplied by the descending branch of the inferior gluteal artery. Anatomy and technique
Regional Fasciocutaneous FlapsThe use of fasciocutaneous flaps in perineal reconstruction is well described and the vascular anatomy of the perineal region is quite distinct. The super-fascial plane contains 3-5 segmental musculocutaneous perforators from the superficial vascular plexus. Venous drainage is by way of vena comitantes, thus a proximally based fascial cutaneous thigh flap can be designed with the flap base located approximately 5 cm from the perineum to preserve proximal vascular supply. This allows for primary closure of the donor site. The anterolateral thigh perforator (ATP) flap has enjoyed recent success in perineal reconstruction. Pedicled ATP island flaps can be used for reconstructing perineal defects up to 20 cm in size. Although the vascular anatomy is quite variable, it is well-described as a septocutaneous or musculocutaneous perforator (Wang, 2006). Subcutaneous and musculocutaneous perforators differ from the gracilis musculocutaneous flap. When the defect is superficial and dead space obliteration is not required, these may be appropriate flaps for perineal reconstruction. However, in the irradiated field or if postoperative radiation is planned, use caution in the design of these regional flaps. COMPLICATIONSSection 7 of 10
A common complication is ischemia of the overlying skin paddle, resulting in delayed healing or partial or complete skin paddle loss. This often is related to an imprecise location of the skin island territory over the gracilis muscle or failure to include perforators to the overlying skin. The skin paddle can be positioned accurately by carefully marking the patient prior to induction of anesthesia in a standing position, drawing a line from the pubic tubercle to the distal semitendinosus tendon. This outlines the anterior border of the skin paddle and the gracilis muscle. With the patient anesthetized and in the lithotomy position, posterior displacement of the skin paddle occurs due to gravity, allowing for inaccurate marking and malposition of the flap skin territory. Another common mistake is to inadequately harvest the septocutaneous perforators with the elevation of the muscle, causing ischemia of the overlying skin paddle. This may be prevented by dissecting the fascia widely on either side of the narrow gracilis muscle, including additional perforators with the flap. The muscle still may be used if the skin paddle is not perfused. OUTCOME AND PROGNOSISSection 8 of 10
Gracilis myocutaneous reconstruction of perineal defects has the added advantages of reliability and long-standing use. Since its original description by Dr McCraw, it has proved to be a time-honored workhorse for perineal reconstruction. Functional donor site morbidity is minimal, with the other thigh adductors serving to take over muscular function. In addition, the bulk of these flaps provides soft tissue fill where required. However, the bulk may limit the aesthetics of the reconstruction if the defect is more superficial. The rectus abdominis flap provides several advantages over bilateral gracilis flap reconstruction. The robust skin paddle can be de-epithelialized for bulk or tubed for neovaginal reconstruction. This flap is well perfused by the deep inferior gastric artery and provides adequate muscle bulk to obliterate dead space. The skin island is versatile both for resurfacing the perineal region and for reconstructing the vaginal vault. The split gluteus maximus myocutaneous flap and the gluteal thigh flap are particularly useful in resurfacing pelvic defects. They both provide a reliable, versatile reconstruction of perineal defects with low donor site morbidity. In addition, the gluteal thigh flap may remain sensate when taken with the posterior thigh sensory branch and may be de-epithelialized and tubed for distal vaginal reconstruction. "Dog ear" formation remains a problem at the medial rotation point and may require secondary revision. Regional fasciocutaneous flaps remain useful in perineal reconstruction when the defect is superficial. When dead space obliteration is not required, they may provide a more cosmetic contour than musculocutaneous flaps. However, use caution in the irradiated field or if postoperative radiation is planned. MULTIMEDIASection 9 of 10
REFERENCESSection 10 of 10
Perineal Reconstruction excerpt Article Last Updated: Jun 18, 2006 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
