First, the good news: We have numerous techniques to choose from to repair prolapse of the vaginal vault, which affects as many as 50% of parous women.1 The bad news: Most of the data on these techniques are anecdotal or retrospective, not the result of randomized, controlled trials. Few investigators have compared the vaginal and abdominal approaches.
So how should we decide on a procedure? It is a judgment call, ultimately. After taking into account the patient’s age, functional status, comorbidities, desire for coitus, and surgical history, the surgeon must weigh the risks and benefits of the procedures that seem most appropriate. Part 1 of this 2-part article reviews what is known about the most widely used and newest vaginal techniques:
- sacrospinous ligament fixation,
- iliococcygeal fixation,
- modified McCall culdoplasty,
- high uterosacral ligament suspension with fascial reconstruction, and
- posterior intravaginal slingplasty (infracoccygeal sacropexy).
In Part 2, next month, we focus on the abdominal approach, and survey the data comparing vaginal and abdominal repairs.
Unfortunately, success and failure rates are still poorly defined because of a lack of standardization, and because techniques and materials continually change. This underscores the need for better understanding of the pathophysiology of genital prolapse, improved preoperative assessment, and more effective and durable repair techniques.
Why prolapse occurs
Pelvic support involves a complex interplay of anatomic, histologic, genetic, and electrophysiologic factors that, although incompletely understood, are frequently disrupted. For example, MacLennan et al2 reported that 46.2% of women aged 15 to 97 years experience pelvic floor dysfunction; a large retrospective study by Olsen and colleagues3 found that 11.1% of women undergo surgery for prolapse by the age of 80, and 29.2% of these women require repeat surgery.
Here’s what we know about the anatomy of pelvic support:
Ligaments serve as secondary supports
The uterus and upper third of the vagina are held in place over the levator plate by the fibers of the parametrium (cardinal and uterosacral ligaments) and paracolpium. These fibers arise from a broad area on the pelvic sidewall overlying the fascia of the piriformis muscle, the sacroiliac joint, and lateral sacrum. The fibers represent condensations of the endopelvic fascia of the pelvis, acting as suspensory ligaments that run in a predominantly vertical direction to insert into the lateral upper third of the vagina and lateral and posterolateral aspect of the cervical portion of the uterus.
In the normal, healthy pelvis, these suspensory ligaments represent secondary support mechanisms and are not routinely under tension.
Pelvic-floor muscles play leading role
Gosling4 argued that pelvic floor muscle tone is more crucial to normal positioning of the pelvic viscera than are the fascial and ligamentous supports of the pelvic organs. Specifically, the pubococcygeus, iliococcygeus, and puborectalis muscles collectively define the levator ani of the pelvic floor. Fusion of the right and left bellies of the levator ani, behind the rectum and anterior to the coccyx, creates a muscular platform known as the levator plate. This plate provides indirect support for the upper genital tract by acting as a platform against which the upper vagina and other pelvic viscera are compressed during increases in intra-abdominal pressure.
Contraction of the levator ani pulls the levator plate toward the posterior symphysis pubis, minimizing the size of the urogenital hiatus through which the rectum, vagina, and urethra exit the pelvis on their way to the perineum. Weakness in the muscular pelvic floor—whether caused by disuse, pudendal nerve damage, or muscular trauma—increases the size of the urogenital hiatus, and the pelvic organs begin to prolapse through it.
Ultimately, constant tension on the ligamentous supports of the pelvic organs exceeds their tensile strength, and pelvic organ prolapse results.
Goals of surgery
Successful surgery achieves effective and sustained vault support, obliterates any enterocele sac, and repairs the cystocele and rectocele that occur in approximately two thirds of women with vault prolapse.
The broader goals: anatomic and functional restoration of the lower female genital tract and improvement in quality of life.
Surgery can be reconstructive or obliterative. Reconstructive surgery can be performed vaginally, abdominally, or a combination of both.