For a long time, abdominal sacral colpopexy (ASC) has been considered as the optimal treatment for vaginal vault prolapse. In this procedure, the prolapsed vaginal vault is fixed to the anterior longitudinal ligament of the sacrum using polypropylene mesh. After the vaginal vault is dissected and isolated from the bladder and rectum, one end of the mesh is stitched to the vaginal vault, while the other end is sutured to the longitudinal ligament (Fig. 1) [5]. Because the mesh is supporting the vagina, it has greater stability resulting in a high success rate and low recurrence rate. On the other hand, ASC is associated with a relatively long operating time and hospital stay, greater blood loss, and higher risk of serious complications.

There are numerous vessels next to the sacrum, and a safe space to suture is limited. To make matters more complicated, vessel locations vary among patients, and their routes are difficult to anticipate. Injury of a vessel can be very dangerous, carrying a heavy burden to surgeons. In addition, the ureter is very close to the midsacral promontory, which is a landmark for sacrocolpopexy and its location varies among patients [6] (Fig. 2) [5].

Numerous studies have compared ASC with other procedures for vaginal vault prolapse. In 2014, Milani et al. [7] performed an observational cohort study comparing ASC (n=41) with ICG (n=36) in patients with symptomatic vaginal vault prolapse who had undergone prior hysterectomy. Both procedures achieved restoration of normal anatomy and improvement of related symptoms with similar rates of postoperative complications.

Traditionally, sacrocolpopexy has been performed via an open transverse abdominal route; however, more recently, robotic or laparoscopic sacrocolpopexy is commonly performed. In a previous prospective multicenter trial, Freeman et al compared open (n=27) and laparoscopic (n=26) sacrocolpopexy for posthysterectomy vaginal vault prolapse [8]. Point C after 1 year (the primary objective outcome) was -6.63 for open sacrocolpopexy and -6.67 for laparoscopic sacrocolpopexy, which was not significantly different. Subjective outcomes also showed equivalence between methods. Therefore, open sacrocolpopexy is no longer the only procedure for correcting vaginal apical prolapse.

Although McCall culdoplasty was not originally developed for vaginal vault prolapse, it is known to help prevent prolapse recurrence after hysterectomy. Among the various methods of suspending the vaginal apex while performing vaginal hysterectomy, the most common procedure is McCall culdoplasty. It is performed by obliterating the posterior cul-de-sac and plicating the uterosacral ligaments across the midline [9,10] (Fig. 3) [5]. In a large study conducted at the Mayo clinic, prolapse did not recur in a high percentage of patients who underwent McCall culdoplasty, and most were satisfied with the result [11]. Therefore, McCall culdoplasty seems to be efficient in preventing vaginal vault prolapse in primary repair after hysterectomy with minimal morbidity.

SSLF is a common procedure for treating apical vault prolapse via a vaginal route. Introduced in 1958 by Sederl in Germany [12], SSLF involves attaching the vault to the sacrospinous ligament, approaching through the dissected pararectal space (Figs. 4, 5) [5]. The sacrospinous ligament is located between the ischial spine and the lower part of sacrum and coccyx, lying within the coccygeus muscle, which is often referred to as the coccygeus-sacrospinous ligament complex (Fig. 4) [5]. The vaginal vault can be anchored to unilateral or bilateral ligament. If performed unilaterally, the end of the vagina is deviated to one side. There have been numerous studies on SSLF, which have revealed a low recurrence rate of 2.4% to 19% [9]. Despite the low recurrence rate, prolapse of the anterior compartment seems to recur more easily than that of the posterior compartment [13]. Several authors have suggested that this is due to deflection of the vagina toward the posterior direction, which pulls the anterior vaginal wall posteriorly, and exposes the anterior compartment to heavy weight bearing [14]. According to a previous study on postoperative complications of SSLF, neurologic symptoms, such as buttock pain, occurred immediately after surgery in up to 50% of patients. In 15% of patients, symptoms were still not resolved after 6 weeks, and 2% eventually underwent an intervention, such as pain block [15]. However, a retrospective review of 95 patients comparing both objective and subjective outcomes between ASC and SSLF reported that both procedures significantly improved patient's subjective outcomes, including sexual function and quality of life [16].

As seen in Fig. 6 [5], the anchoring point of the vaginal vault is deeper and more posterior in SSLF than in other procedures. As such, there are numerous vessels and nerves nearby, including the pudendal and sciatic nerves, resulting in a high risk of postoperative complications.

USLS is another method of apical vault fixation via a vaginal approach. However, its intraperitoneal approach is different from SSLF, which can be performed via an extraperitoneal route. USLS has become a common procedure since it was first introduced by Miller in 1957. When performing McCall culdoplasty, the uterosacral ligament is also used to suspend the vaginal vault, followed by internal McCall sutures [10].

In traditional USLS, the uterosacral ligament is plicated at or above the ischial spine level (Figs. 6, 7) [5]. Recently, a modified procedure, referred to as modified high USLS, has been developed. The suture site can be seen in Fig. 6 [5]. High USLS may involve passage of the suture through the coccygeus-sacrospinous ligament complex muscle complex, because a portion of the uterosacral ligament inserts into this structure [5].

According to a previous meta-analysis of USLS, the pooled rate for successful anatomical outcome in the apical compartments was 98.3% (95% confidence interval, 95.7% to 100%). In addition, subjective symptoms were relieved in 82% to 100% of patients, providing evidence that USLS is a highly effective procedure [17].

Recently, in the Operations and Pelvic Muscle Training in the Management of Apical Support Loss trial, Barber et al. [18] conducted a multicenter, randomized study comparing USLS and SSLF in 374 women. After 2 years of follow-up, SSLF (63.1%, 94/149) and USLS (64.5%, 100/155) showed similar success rates (adjusted odds ratio, 1.1; 95% confidence interval, 0.7 to 1.7). In addition, surgical outcomes, including functional and anatomical results, were not significantly different between the 2 procedures. Interestingly, however, incidence of neurologic symptoms was higher in SSLF (12.4%) than in USLS (6.9%) (P=0.0749). On the other hand, there were 6 cases (3.2%) of ureteral complication, such as ureter obstruction, in USLS, while there were 0 cases in SSLF. Because the ureter is located closer to the suture site in USLS than in SSLF, and there are more nerves near the sacrospinous ligament compared with the uterosacral ligament, this result is quite predictable.

With regard to complications, according to a retrospective chart review of 983 women, patients who underwent USLS had an adverse event rate of 31.2%, including urinary tract infection in 20.3%. There was no intraoperative ureteral injury, but 4.5% of patients required suture removal due to ureteral kinking [19]. Although two-thirds of those who underwent suture removal maintained unilateral USLS and did not undergo resuturing, there was no significant difference in recurrence rate.

ICG was first introduced by Inmon in 1963 [20] for patients whose uterosacral ligament was difficult to be identified or insufficient to support the vaginal vault, and was modified by Shull et al. in 1993 [21].

It also was developed to avoid the possible vessel and nerve injury associated with SSLF. The initial pararectal dissection in ICG is similar to that in SSLF, but the suture site to attach the vaginal vault is different. ICG utilizes the fascia of the iliococcygeus muscle just below the ischial spine and lateral to the rectum, where there are much fewer major vessels and nerves (Figs. 8, 9) [22].

Because of this different site of vaginal fixation, the vaginal axis is not distorted significantly and is not deviated anteriorly or posteriorly, as in SSLF. In addition, mean vaginal length is not significantly shortened after ICG surgery [23]. In reports comparing vaginal length before and after SSLF, vaginal length was significantly shortened after surgery [23,24].

According to a prior study comparing ICG and ASC, both procedures achieved restoration of normal anatomy and improvement of related symptoms [6]. However, because there are less vessels and nerves close to the operating site in ICG than in ASC, ICG might be a good alternative to ASC.

In a prospective study of ICG in 44 women, the objective cure rate was reported to be 84.1% (37/44), while the rate of successful subjective outcome was 88.6% (39/44) at a median follow-up of 68 months [25]. Therefore, according to previous studies, ICG can achieve good long-term objective and subjective results.

All the procedures described in this article, except for sacral colpopexy, aim to fix vaginal apical prolapse by using the patient's own native tissue. There is another technique to fix vaginal apex that uses mesh and a transvaginal approach. However, when using mesh, there are risks of erosion, pain, vaginal immobility, and discomfort.

In 2012, Sokol et al. [26] conducted a multicenter, double-blind, randomized controlled trial of transvaginal polypropylene mesh. They compared vaginal prolapse repair using USLS (n=33) or mesh (n=32; Prolift, Ethicon Women's Health and Urology, Somerville, NJ, USA) in 65 women with POP-Q prolapse stage 2 to 4. Twelve months after prolapse repair, significant objective and subjective improvements were seen with or without interpositional mesh. However, use of mesh resulted in exposure in 15.6% of patients (5/32 subject). Three of five exposures required surgical procedure to remove mesh and 3 patient had reoperation for prolapse, whereas no patient in the no-mesh group required a reoperation (P=0.017)

Currently, no long-term outcome data are available on vaginal mesh, and the optimal size and material have not been established. Therefore, when using mesh in vaginal apical prolapse repair, careful patient selection and counseling, including the risks and benefits, are required.