Chapter 17: Rectus Abdominis Flaps and Pudendal Thigh and Related Flaps

BACKGROUND

Reconstruction of the vulvovaginal and pelvic region can be a complex and formidable undertaking. Defects from oncologic resection can be extensive and variable. The increasing use of adjuvant radiation therapy and chemotherapy further adds to the challenge of achieving uncomplicated wound healing. Trends indicate that patients are being diagnosed with gynecologic malignancies at younger ages, and with better treatments, long-term survival has increased.^1,2,3,4 Longer survival results in a higher risk of local recurrence, which can complicate reconstruction, because the operative field in such patients is often scarred and radiated. The goals of reconstructing vaginal defects are manifold: to restore normal anatomy, to facilitate primary wound healing, to fill in dead space in the pelvis with healthy tissue, to restore support of the pelvic floor, and to create a neovagina that allows for sexual activity.

Vaginal reconstruction comprises techniques designed to ameliorate defects not just from extirpative procedures but also from congenital vaginal agenesis. However, regardless of the cause of the defect, the ultimate goal is the same: to restore a vagina that maintains sexual function and body image. From the original nonoperative technique of stenting and dilatation by Frank⁵ to skin graft inlay combined with stenting by McIndoe^6,7, to some of the more established flap techniques—including the gracilis myocutaneous flap,^8,9,10,11,12 the medial thigh flap, the rectus flap, the omentum, and various fasciocutaneous flaps—there is no one ideal method for reconstruction.^{13,14,15,16,17,18,19,20} However, flaps must be able (1) to provide a reliable amount of skin and subcutaneous fat and/or muscle into the defect, to produce a functional outcome, (2) to provide a sensate flap, when needed, (3) to minimize donor site morbidity, and (4) to achieve an aesthetic outcome.

Vaginal defects can be reconstructed using a number of locoregional flaps. A detailed assessment of the wound must be performed before selection of the flap. To better visualize the range of vaginal defects, the vagina can be represented as a coned cylinder, as shown in Figure 17-1.^21,22 The opening of the cone is the introitus. The anterior wall of the vagina is adjacent to the bladder, the lateral walls are next to the pelvic musculature, and the posterior wall is in proximity to the rectum. Vaginal defects are classified, on the basis of these anatomic considerations, into 2 general categories: partial defects (type I) and circumferential defects (type II; see Figure 17-1). Type I defects are further classified as either anterior or lateral wall defects (type IA); these often result from bladder or urinary tract malignancies or from primary vaginal malignancies. Type IB defects are posterior wall defects and often are caused by colorectal cancers. Type II defects are circumferential defects and are further divided into type ...