INTRODUCTION — Stress urinary incontinence (SUI) affects 4 to 35 percent of women [1,2]. SUI occurs when an increase in intraabdominal pressure exceeds urethral closure pressure, resulting in the involuntary leakage of urine. This may occur with exertion, sneezing, or coughing [3].
Management options for SUI include conservative and surgical treatments. Midurethral slings are a relatively new treatment option, but have become the procedure of choice for many women. The first midurethral sling, introduced in 1996, was placed by passing trocars with mesh through the retropubic space [4]. Retropubic midurethral slings are still commonly used, but transobturator slings were introduced in 2001 with the goal of avoiding some of the complications of retropubic insertion (eg, bladder perforation, vascular injury, bowel injury) [5]. Transobturator slings are placed by passing trocars with mesh through obturator canal and avoiding the retropubic space completely.
Transobturator midurethral sling procedures are reviewed here. Retropubic midurethral slings and the approach to choosing a procedure for SUI in women are discussed separately.
●(See "Surgical management of stress urinary incontinence in females: Retropubic midurethral slings".)
●(See "Surgical management of stress urinary incontinence in women: Choosing a type of midurethral sling".)
●(See "Female stress urinary incontinence: Choosing a primary surgical procedure".)
In this topic, when discussing study results, we will use the terms "woman/en" or "patient(s)" as they are used in the studies presented. However, we encourage the reader to consider the specific counseling and treatment needs of transgender and gender diverse individuals.
TERMINOLOGY — There are several types of sling procedures for treatment of SUI in women (table 1). These procedures vary by the location of the sling and by the sling material. Collectively, these slings are referred to as suburethral slings, which is a sling that is inserted through a small vaginal incision and attached to another structure in the pelvis for the purpose of supporting the urethra. Suburethral slings may be either bladder neck and midurethral slings.
●Midurethral sling – A suburethral sling that is placed at the level of the midurethra in a tension-free manner. These slings are made of synthetic mesh.
•Retropubic midurethral slings (eg, tension-free vaginal tape [TVT]) are inserted through the retropubic space and exit through the abdominal wall in the suprapubic area (figure 1).
•Transobturator midurethral slings are inserted through the two obturator foramens and exit through the skin of the groin area (figure 2).
•Single incision midurethral slings differ from full-length retropubic and transobturator slings in two ways: they are shorter (approximately 8 cm rather than 40 cm), and they require only a vaginal incision, not an abdominal incision. Different types of these slings may be placed in a retropubic (anchored to the urogenital diaphragm) or transobturator fashion (anchored to the obturator internus muscle).
●Bladder neck sling – A suburethral sling that is placed at the level of the proximal urethra and bladder neck (figure 3). This procedure is usually performed using both vaginal and abdominal incisions. These slings can be made of either biologic materials (including the patient's own tissue) or synthetic mesh.
Bladder neck slings are also referred to as proximal urethral slings. Alternatively, they are referred to as pubovaginal slings when the arms of the sling material are affixed to the anterior rectus fascia rather than the pubic bone or Cooper's ligament [6].
MECHANISM OF ACTION — Midurethral slings involve the introduction of a polypropylene tape (approximately 1 cm in width) covered in a plastic sheath beneath the midportion of the urethra. Transobturator slings, similar to their retropubic counterpart, function as a backboard, which offers resistance beneath the urethra during increases in intraabdominal pressure, but not at rest. Ultrasound data suggest that continence is achieved by compression of the urethra between the sling and the pubic symphysis [7,8].
In transobturator procedures, the sling traverses the skin in the groin, the obturator foramen, posterior to the adductor longus tendon, and a midurethral vaginal incision (figure 2). The sling lies under the midportion of the urethra at a less acute angle than the retropubic technique and is, therefore, thought to be less likely to cause obstruction [9]. Once the plastic sheaths are removed, the tape is held in place without suture by its interface with the patient’s tissue. The friction which initially secures the mesh is eventually reinforced with tissue fibrosis into the mesh. Porcine models demonstrate that 74 percent of the final strength has already been achieved by two weeks postoperatively and maximum strength of tissue in-growth into polypropylene mesh occurs at three months [10].
SURGICAL CANDIDATES
Indications and special considerations — Indications and special considerations are the same for transobturator as for retropubic midurethral slings. Indications for midurethral sling placement are:
●Symptomatic SUI
●Women who are planning repair of prolapse of the vaginal apex and who have known or suspected occult SUI
Evaluating whether a woman with SUI is an appropriate candidate for surgical treatment, and a midurethral sling in particular, may depend upon additional factors (eg, intrinsic sphincter deficiency, age, obesity). The choice of anti-incontinence surgery in women with additional urinary function issues, obesity, and advanced age are discussed in detail separately.
Indications and special considerations for women planning anti-incontinence surgery are discussed in detail separately. (See "Surgical management of stress urinary incontinence in females: Retropubic midurethral slings", section on 'Surgical candidates' and "Female stress urinary incontinence: Choosing a primary surgical procedure", section on 'Special populations' and "Female stress urinary incontinence: Choosing a primary surgical procedure", section on 'Coexistent anatomic or functional abnormality'.)
Contraindications — Contraindications to midurethral transobturator sling placement include:
●Current urinary tract infection
●Current pregnancy
●Anticoagulation (relative)
Current pregnancy is an absolute contraindication to midurethral sling placement. Plans for future pregnancy are a relative contraindication. Since pelvic support may be disrupted during pregnancy, and particularly following a vaginal birth, most clinicians recommend delaying surgical management of SUI until childbearing has been completed. (See "Female stress urinary incontinence: Choosing a primary surgical procedure", section on 'Women finished with childbearing'.)
Midurethral sling placement involves passing trocars through several tissue layers and may result in hematoma formation or hemorrhage. The risk of hematoma formation is probably more with retropubic approaches than with transobturator approaches, so women with bleeding diatheses (eg, Von Willebrand’s) may be better served with administration of preoperative control measures (eg, desmopressin) and a transobturator approach.
Preexisting synthetic mesh in the path of trocar placement may result in difficulty with proper sling placement, but a previous midurethral sling is not a contraindication to placement of another midurethral sling [11]. Treatment of recurrent SUI is discussed separately. (See "Stress urinary incontinence in females: Persistent/recurrent symptoms after surgical treatment", section on 'Midurethral sling'.)
CHOOSING A TYPE OF TRANSOBTURATOR SLING — There are two variations of transobturator midurethral sling procedures, which vary by direction of trocar insertion:
●Inside-out – The trocars are passed from a midurethral vaginal incision to exit through bilateral groin incisions (TVT Transobturator, often abbreviated as TVT-O).
●Outside-in – The trocars are passed from bilateral groin incisions to exit through a midurethral vaginal incision (Monarc, often abbreviated as TOT).
The two types of transobturator procedures appear to be equally effective up to 10 years from surgery [12], and have similar complication rates. A meta-analysis of four randomized trials comparing the inside-out with the outside-in approach found no significant differences in subjective SUI cure rate (OR 1.37, 95% CI 0.93-2.00); objective cure rate (OR 1.06, 95% CI 0.65-1.73); voiding difficulty (OR 1.23, 95% CI 0.27-5.69); and de novo urgency symptoms (OR 0.98, 95% CI 0.42-2.31) [13]. However, this analysis was limited by insufficient statistical power.
One disadvantage of the outside-in approach is that it results in a larger vaginal incision and has a higher rate of vaginal perforation (in a trial of 341 women, 17 versus 3 [14]), based upon data from randomized trials [15]. On the other hand, some data suggest that the inside-out approach is more likely to cause groin pain, but this finding has varied across studies [14-16]. One possible explanation for a higher incidence of postoperative pain with the inside-out approach is based upon a cadaveric study, which found that the trocars of the TVT-O device were passed closer to nerves and vessels than the TOT [17].
In our practice, we perform the inside-out procedure, because it requires small incisions and is also easier to teach to trainees. However, the evidence is insufficient to recommend either the inside-out or outside-in approach.
Choosing between retropubic, transobturator, and single incision midurethral slings is discussed separately. (See "Surgical management of stress urinary incontinence in women: Choosing a type of midurethral sling".)
PREOPERATIVE EVALUATION AND PREPARATION — Women who are planning primary midurethral transobturator sling placement should undergo preoperative evaluation to confirm the diagnosis of SUI, exclude other etiologies of urinary incontinence, and assess surgical risk.
Preoperative evaluation and preparation of women for midurethral sling placement and general gynecologic preoperative issues are discussed in detail separately.
●(See "Overview of preoperative evaluation and preparation for gynecologic surgery".)
PROCEDURE
Operative setting — Midurethral sling placement is typically performed in an operating room as an outpatient procedure. Consistent with others, we recommend antibiotic prophylaxis for surgical site infection for midurethral sling placement (table 2). (See "Antimicrobial prophylaxis for prevention of surgical site infection in adults".)
Anesthesia — Midurethral sling placement may be performed under local, regional, or general anesthesia. We suggest use of local or regional anesthesia rather than general anesthesia, since general anesthesia has been associated with lower SUI cure rates in prospective studies [18,19]. Local anesthesia may be combined with conscious sedation. In addition, if local anesthesia is used, it should be administered to the vaginal incision site as well as the groin areas where the trocar and mesh will exit.
Use of anesthesia for midurethral sling placement is discussed in detail separately. (See "Surgical management of stress urinary incontinence in females: Retropubic midurethral slings", section on 'Anesthesia'.)
Instrumentation
●Transobturator tape system – A polypropylene mesh tape (typically 40 cm long and 1 cm wide) covered by a plastic sheath and fixed to the helical trocars.
●Bladder (Foley) catheter (size 16 French)
●Cystoscope
Patient preparation
●Patient set-up – Position the patient in dorsal lithotomy with careful attention to avoid nerve compression. (See "Nerve injury associated with pelvic surgery" and "Nerve injury associated with pelvic surgery", section on 'Prevention of nerve injury'.)
Sterilely prepare and drape the patient. Insert the bladder catheter. The bladder should be completely drained prior to insertion of the trocars.
●Marking groin incisions - Mark the two planned groin exit points at the level of the clitoris, 2 cm lateral to the genitofemoral folds.
●Hydrodissection – Some surgeons hydrodissect the vaginal incision site and/or the path of the trocars. Either local anesthetic (with or without epinephrine) or sterile saline may be used. Fluid may be injected into the vaginal wall sub- and paraurethrally. Injection in the vaginal sulci through the vagina is another adaptation that has been reported; some surgeons aggressively hydrodissect the anterior vaginal sulci to displace the sulci posteriorly to theoretically reduce the risk of vaginal perforation.
Sling placement
Inside-out — There are multiple different products on the market that utilize similar techniques. The procedure described here is for the TVT Transobturator [20]. The mean operative time for this procedure is 25 minutes [21]. A video of the procedure is included (movie 1).
●Midurethral vaginal incision - Make a vaginal incision, 1 cm proximal to the urethral meatus and 1 to 1.5 cm in length to accommodate the width of the sling in the appropriate location. Place Allis clamps on the lateral edges of the incision to provide exposure by retracting the vaginal mucosa laterally.
The inside-out technique may be performed with smaller incisions, since a finger does not need to be introduced into the tract, as it does for an outside-in technique.
●Dissecting the tract for the trocar and mesh – Use the Metzenbaum scissors to perform a minimal dissection lateral to the midurethra, between the vaginal mucosa and the pubocervical fascia. The scissors are aimed towards the obturator foramen behind the inferior pubic ramus.
A winged guide (provided in the TVT Transobturator kit) can then be introduced into the tract to guide the trocars into the obturator region. Many surgeons use the winged guide to perforate the obturator membrane.
●Inserting the trocars – Insert the trocars through the obturator foramen, posterior and medial to the obturator vessels. The trocars traverse the periurethral endopelvic fascia, obturator internus muscle, obturator membrane, obturator externus muscle, and exit out through the skin. The trocar should pass just posterior to the adductor longus tendon.
Trocars should be passed while hugging the pubic rami. The obturator canal (obturator nerve and vessels) is located at the opposite, anterolateral margin of the obturator foramen, approximately 3.5 to 4.0 cm lateral to the zone of safe needle passage [5].
Exit through the marked groin incisions, 2 cm lateral to the genitofemoral folds at the level of the clitoris. The vaginal sulci are inspected to ensure that they have not been compromised.
●Cystourethroscopy – We suggest cystourethroscopy after both trocars have been placed. Although the risk of bladder perforation is lower than in retropubic sling procedures, bladder and urethral perforations have been reported for transobturator procedures. The morbidity of the urinary tract injury is reduced with intraoperative recognition and appropriate repositioning of the trocar. (See 'Bladder or urethral injury' below.)
A 70 degree cystoscope should be used and the bladder filled adequately to allow complete examination of the urethra and bladder surface [4].
●Adjusting sling tension – The sling functions by preventing descent of the midurethra during intraabdominal pressure events and it should not compress the urethra at rest. In the authors' opinion, there should be a small visible gap between the sling and the urethra at rest when adjustment is final.
There are several approaches to ensure that the sling is tension-free and does not compress the urethra while the patient is at rest. No single approach has been proven superior to another and selection depends on surgeon preference.
•Sling elevation – Many surgeons insert an instrument (eg, Kelly clamp, needle driver, Mayo scissors, number 8 Hegar dilator) between the sling and the urethra while adjusting the sling tension.
•Sling pinch – Others have used a Babcock clamp to pinch a segment of the mesh under the urethra during insertion that then ensures some laxity in the sling when this clamp is released after adjustment. The important concept is that the sling functions by preventing descent of the midurethra during intraabdominal pressure events and it should not compress the urethra at rest. In the authors' opinion, there should be a small visible gap between the sling and the urethra at rest when adjustment is final.
An intraoperative urinary (cough) stress test may be performed at this time if the patient is under local anesthesia. If leakage occurs, the sling is tightened slightly. Performing the urinary stress test during sling placement is discussed separately. (See "Surgical management of stress urinary incontinence in females: Retropubic midurethral slings", section on 'Anesthesia'.)
With the spacer in place, remove the plastic sheaths; this prevents excess tightening of the mesh. The surgeon should assess the entire plastic sheath to confirm that it has been completely removed.
Trim the mesh at the groin incisions. Mesh protrusion and irritation at the skin surface can be prevented by depressing the skin slightly to trim the mesh just below the skin surface. The authors keep the spacer in place during mesh trimming to prevent further tightening during mesh elevation for trimming. The mesh does not require suturing since it is held in by friction and then fibrosis [4].
●Closure of incisions
•Vaginal incision – At our institution, we close the vaginal mucosa with a horizontal mattress configuration to evert the incisional edges and theoretically reduce the risk of mesh exposure. We use an absorbable suture [22].
•Groin incisions – This can be performed in a variety of ways (suture, adhesive strips, surgical glue, no closure), based upon surgeon preference.
Outside-in — The unique steps of the outside-in are described in this section [5].
●Midurethral vaginal incision – Make a vaginal incision, 1 cm proximal to the urethral meatus and 1 to 1.5 cm in length to accommodate the width of the sling and the surgeon’s finger in the appropriate location. Place Allis clamps on the lateral edges of the incision to provide exposure by retracting the vaginal mucosa laterally.
●Dissecting the tract for the trocar and mesh – Use the Metzenbaum scissors to perform a dissection lateral to the midurethra, between the vaginal mucosa and the pubocervical fascia. The tract should be large enough that a finger can be introduced into it. The scissors are aimed towards the obturator foramen behind the inferior pubic ramus.
The operator’s finger is then placed into the tract created by the Metzenbaum scissors to the obturator foramen.
●Making groin incisions and inserting the trocars – Make incisions bilaterally, 2 cm lateral to the genitofemoral folds at the level of the clitoris.
Pass the trocars through the groin incisions and rotate the trocars through the obturator membrane. The trocars traverse the skin, obturator externus muscle, obturator membrane, obturator internus muscle, periurethral endopelvic fascia, and out through the vaginal incision. The trocar should pass just posterior to the adductor longus tendon.
A finger is placed via the vaginal incision through the tract to guide the trocars and avoid injury of the vaginal sulci. The trocars exit at the vaginal incision.
The mesh is attached to the tips of the trocars and the trocars are backed out, bringing the mesh out through the level of the skin in the groin region.
The vaginal sulci are inspected to ensure that they have not been compromised.
●Continue as for inside-out placement – Perform cystourethroscopy, and then continue with the subsequent steps of inside-out placement. (See 'Inside-out' above.)
Postoperative voiding trial — A voiding trial is performed prior to patient discharge. A voiding trial can be performed in two different ways: retrograde or spontaneous filling of the bladder. A discussion of the two types of bladder filling can be found separately.
●(See "Perioperative patient care issues in female pelvic reconstructive surgery".)
Of note, at least one small study has reported an increase in unsuccessful voiding trials after transobturator sling placement in women who received preoperative transdermal scopolamine (TDS) patches to prevent postoperative nausea and vomiting compared with those who did not (54 versus 7 percent) [23]. It is not known if TDS patches are more likely to cause urinary retention after transobturator slings compared with retropubic slings.
COMPLICATIONS — Transobturator insertion of midurethral slings was developed to avoid some of the complications of retropubic slings (eg, bladder perforation, vascular injury, bowel injury). This appears to have been largely successful, and few serious or long-term complications have been reported following transobturator midurethral sling procedures [24-27]. In a large retrospective cohort study based in the United States that included 17,030 patients who underwent synthetic midurethral sling, the rate of reoperation for sling revision or removal was 1.1 percent over nine years and was not different among sling types [28]. The rate of reoperation for recurrent SUI was 4.6 percent in the transobturator approach compared with 3.7 percent in those who underwent the retropubic approach, but this did not meet statistical significance.
Similar to retropubic slings, transobturator slings may result in voiding dysfunction, although the overall rate of this is lower. In addition, women who have undergone transobturator sling placement may experience groin pain, a complication that is not commonly found with retropubic placement.
Choosing between retropubic and transobturator midurethral sling procedures is discussed separately. (See "Surgical management of stress urinary incontinence in women: Choosing a type of midurethral sling", section on 'Retropubic versus transobturator midurethral slings'.)
Urinary tract complications
Persistent stress incontinence — The midurethra is considered the continence zone of the urethra and careful positioning of the sling beneath this portion of the urethra has been shown to achieve the highest rates of continence. For patients who present with persistent SUI, surgeons should assess the position of the sling. This may be assessed with physical examination and/or imaging studies.
On examination, the examiner should palpate along the urethra. Urethral hypermobility should also be assessed. (See "Surgical management of stress urinary incontinence in females: Preoperative evaluation for a primary procedure", section on 'Assessing urethral mobility'.)
There is emerging research using 3-D transperineal, translabial, and endovaginal ultrasound that correlate the position of the sling with surgical outcomes [29]. Ultrasound can also differentiate between transobturator and retropubic slings, provide information on mesh type, and locate mesh and mesh position, which can often be difficult to find on physical examination [30]. As an example, a case control study evaluated 100 women who underwent transobturator sling surgery with 3-D transperineal ultrasound [31]. The study found that a transobturator sling that moved concordantly with the urethra during dynamic testing, was located in the mid urethra, and deformed appropriately with stress maneuvers was associated with the best success rates. Failed slings were often positioned too proximally.
When a midurethral sling is too proximal, continence can be achieved by placing a repeat midurethral sling properly under the midurethra without removing the non-functioning sling.
The best ways to prevent a midurethral sling from being too proximal is to start the vaginal incision for the midurethral sling 1 cm from the urethral meatus as recommended in the original tension-free vaginal tape publication, and to never use an anterior repair incision to place the midurethral sling. (See "Surgical management of stress urinary incontinence in females: Retropubic midurethral slings", section on 'Sling placement'.)
Voiding dysfunction — Voiding dysfunction is commonly reported after midurethral sling placement [32]. The reported rate of voiding dysfunction following transobturator sling procedures is 4 to 11 percent [33,34]. The diagnostic criteria for voiding dysfunction vary across studies and institutions. In our practice, we define incomplete bladder emptying as a postvoid residual volume of >150 ml.
Postoperative voiding dysfunction is typically managed initially with bladder catheterization. Urinary retention that persists for four to six weeks may require a release of the sling. In one study of 205 women who underwent transobturator sling placement, for example, 1.5 percent required sling release or urethrolysis [35].
Evaluation and management of voiding dysfunction associated with midurethral sling procedures are discussed separately. (See "Surgical management of stress urinary incontinence in females: Retropubic midurethral slings", section on 'Voiding dysfunction'.)
Urinary urgency — A systematic review of 32 studies (5 trials and 27 observational studies) that evaluated the incidence of de novo OAB reported de novo OAB rates of 8.7 percent for the inside-to-outside approach and 11.2 percent for outside-to-inside [36]. The de novo OAB rate was not found to be different between types of slings (mini slings or retropubic approaches).
Evaluation and management of urinary urgency symptoms are discussed separately. (See "Female urinary incontinence: Evaluation".)
Urinary tract infection — Recurrent urinary tract infection has been reported in some patients after midurethral sling placement (6.4 percent in one series of 117 women who underwent transobturator sling placement [37]) [35,38]. Urinary tract infection should be treated, as appropriate.
Bladder or urethral injury — Bladder injury has been reported in 0 to 1 percent of women following transobturator sling placement [27,34,39,40]. A meta-analysis of 55 trials reported that bladder injury rate is much lower after transobturator sling placement than retropubic (0.6 versus 4.5 percent; relative risk 0.13, 95% CI 0.08-0.20; 40 trials, 6372 women) [41].Urethral injury is a rare, but potentially morbid, complication. Urethral perforation was reported in 2 of 2543 transobturator procedures in a voluntary registry study [40]. Evaluation and management of bladder or urethral injury associated with midurethral sling procedures are discussed separately. (See "Surgical management of stress urinary incontinence in females: Retropubic midurethral slings", section on 'Bladder injury'.)
Other urinary tract complications — Urinary tract fistula is a rare, but serious, complication of midurethral sling placement [42,43].
Evaluation and management of urinary tract fistulas are discussed separately. (See "Urogenital tract fistulas in females".)
Postoperative pain
Groin pain — Groin pain occurs in approximately 12 to 16 percent of women following a transobturator sling procedure [34,38,44]. The pain is usually described as in the groin area as the patient abducts or adducts her legs. Usually the pain is deep within the muscle rather than superficial at the skin. The patient can usually feel this pain immediately after surgery and typically it improves over time. Some studies suggest that groin pain is more likely following inside-out placement of the sling. (See 'Choosing a type of transobturator sling' above.)
Some data suggest that obesity may be protective against postoperative groin pain. In one study of 226 women who underwent transobturator sling procedures, hip/proximal lower extremity pain was 2.5 times more likely to develop in women with a normal body mass index (18.5 to 24.9) than in obese women (≥30) [44].
In most cases, postoperative groin pain resolves within a few days to weeks, and pain can be managed with application of ice to the site, nonsteroidal anti-inflammatory medications, short-term oral narcotics, or gabapentin.
Persistent pain occurs in some women and may warrant additional measures. Local injection with steroids and anesthetic agents has been proposed [45]. In patients in whom groin pain persists for six or more weeks, sling release may be required. Sometimes, removal of substantial portions of the sling are required to resolve groin pain. This can usually be performed transvaginally, but thigh exploration and removal of sling has also been described [46]. Patients should be counseled that removal of all or part of the mesh will most likely result in recurrent SUI. (See "Surgical management of stress urinary incontinence in females: Retropubic midurethral slings", section on 'Loosening'.)
Sexual function — While vaginal surgery can lead to dyspareunia in some, reduction of urinary incontinence symptoms leads to improved sexual function in other patients.
●Dyspareunia – Dyspareunia has been reported in 1 to 9 percent of women following transobturator sling placement [27,47]. In a prospective trial of 300 women who underwent transobturator sling placement, 4 (1.3 percent) reported dyspareunia; all 4 were managed with sling release and had complete resolution of their complaints and no recurrence of incontinence [47].
●Improved sexual function – A combined secondary analysis including several large trials (total 220 women) reported a clinically important improvement in sexual function as assessed by the validated PISQ-12 questionnaire after treatment with midurethral sling [48].
Vaginal injury
Vaginal mesh exposure — Mesh exposure, also known as erosion, is a common complication when synthetic mesh is used for surgery [49-51]. In a meta-analysis of 55 trials, the mesh exposure rates did not differ for transobturator and retropubic midurethral slings (24 of 1000 versus 21 of 1000, relative risk 1.13, 95% CI 0.78-1.63, 31 trials, 4743 women) [41]. The diagnosis of mesh erosion is made with visual inspection of the vagina.
Issues surrounding the use of transvaginal mesh in incontinence surgery and management of mesh exposure are addressed in the following topics:
●(See "Transvaginal synthetic mesh: Use in stress urinary incontinence (SUI)".)
●(See "Transvaginal synthetic mesh: Management of exposure and pain following pelvic surgery".)
Evaluation and management of synthetic mesh erosion into the bladder or urethra are discussed in the following locations.
Vaginal perforation — Vaginal perforation has been reported in 0.4 to 1.3 percent of women in studies of 500 or more transobturator procedures [40,52]. There is an increased risk of vaginal perforation with the transobturator slings compared to retropubic slings because the course of the sling is flatter and closer to the anterior vaginal fornices. In the Trial of Midurethral Slings (TOMUS) (n = 597; the largest randomized trial comparing retropubic and midurethral slings to-date), more vaginal perforations occurred in the transobturator sling group (4 versus 2 percent) [21]. In women undergoing transobturator sling placement, the outside-in procedure appears to be associated with a greater risk of vaginal perforation. (See 'Choosing a type of transobturator sling' above.)
The vaginal sulci should be inspected and palpated after insertion of the trocars. If a perforation is identified, we remove the trocar and replace the trocar in the appropriate position; sometimes this requires closure of the vaginal perforation defect.
Vascular injury — Vascular injury is uncommon during transobturator sling placement. Injury to the obturator, external iliac, femoral, or inferior epigastric vessels may occur. Vascular injury may result in hematoma formation (1 of 2543 women required reoperation for a retropubic hematoma in a registry study [40]) [53-56] or hemorrhage (0 to 3 percent of procedures) [40,57]. Rarely, a vascular injury is associated with nerve injury [53].
Evaluation and management of vascular injury during midurethral sling procedures are discussed separately. (See "Surgical management of stress urinary incontinence in females: Retropubic midurethral slings", section on 'Vascular injury'.)
Other complications — Rare complications that have been described include necrotizing fasciitis, abscess, and myositis [58-62].
FOLLOW-UP
Postoperative care and instructions — Women may experience vaginal, periurethral, or lower abdominal discomfort and pain at incision sites for up to two weeks following the procedure. These symptoms are typically well controlled with oral narcotics and non-steroidal anti-inflammatory drugs. Many women also have vaginal spotting for up to two weeks.
We counsel patients to call their surgeon if they experience symptoms that may be associated with a serious complication, including:
●Fever
●Heavy vaginal bleeding
●Light-headedness
●Severe or persistent abdominal pain
●Vomiting or persistent nausea
●Discharge of clear fluid or blood from the incision sites that is copious or persistent or any amount of purulent or feculent discharge
Patients who present with these symptoms should be promptly evaluated.
Urinary retention may occur even after a successful postoperative voiding trial. Patients who feel a persistent sense of urinary retention or incomplete bladder emptying should have postvoid residual volume measured and may require catheterization. (See "Surgical management of stress urinary incontinence in females: Retropubic midurethral slings", section on 'Postoperative catheter management'.)
The sling is initially held in place by solely frictional tissue forces, and patients must allow adequate time for tissue in-growth to occur before significant intraabdominal pressure is applied to the mesh. Patients are advised to avoid heavy lifting, actions that increase intraabdominal pressure (eg, straining with constipation), or exercise for at least two to four weeks. Ambulation, however, is encouraged. Sexual activity should be avoided until the vaginal epithelium is healed, which takes approximately four to six weeks.
The patient may return to work when she feels sufficiently comfortable.
We see patients for a routine follow-up visit at four to six weeks. We perform abdominal and vaginal examinations to ensure that the incisions have adequately healed and to check for vaginal mesh erosion. The vaginal sulci are visualized and palpated to confirm that there are no occult extrusions of mesh. We check a postvoid residual volume to assess whether the patient has been adequately emptying her bladder. This can be measured with a bladder ultrasound or catheterization.
Patient information regarding care after pelvic surgery can be found separately. (See "Patient education: Care after gynecologic surgery (Beyond the Basics)".)
Subsequent pregnancy — Since pelvic support may be disrupted during pregnancy, and particularly following a vaginal birth, most clinicians recommend delaying midurethral sling placement until childbearing has been completed, when possible. Pregnancy following midurethral sling placement is discussed separately. (See "Surgical management of stress urinary incontinence in females: Retropubic midurethral slings", section on 'Subsequent pregnancy'.)
OUTCOME — While most patients do well following midurethral sling surgery, a few will have persistent symptoms and undergo repeat surgical treatment.
●Surgical success – Cochrane review of 55 trials evaluating the transobturator route versus the retropubic route for midurethral sling noted short term (<12 months) subjective cure rates of the transobturator approach ranged from 62 to 98 percent, and long term (>5 years) subjective cure rates ranged from 43 to 92 percent [41]. In the Trial of Midurethral Slings (TOMUS) (n = 597; the largest randomized trial comparing retropubic and transobturator slings to-date), for retropubic slings, the 12-month subjective success rate was 62 percent and the objective cure rate 81 percent [21].
●Reoperation rates– Several large studies have confirmed low overall long-term reoperation rates (approximately 6 percent) for the midurethral slings, including reoperations for recurrent SUI or mesh revision/removal [28,63-65].
SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Incontinence surgery in women" and "Society guideline links: Urinary incontinence in adults" and "Society guideline links: Gynecologic surgery".)
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Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)
●Basics topic (see "Patient education: Urinary incontinence in females (The Basics)")
●Beyond the Basics topic (see "Patient education: Urinary incontinence treatments for women (Beyond the Basics)")
SUMMARY AND RECOMMENDATIONS
●Stress urinary incontinence (SUI) is the involuntary leakage of urine with increased intraabdominal pressure. Midurethral sling placement is the procedure of choice for treatment of SUI in many women. Midurethral sling can be placed either through the retropubic or transobturator spaces. (See 'Introduction' above.)
●Contraindications for transobturator midurethral sling placement include current pregnancy or urinary tract infection. Plans for a future pregnancy are a relative contraindication. (See 'Contraindications' above.)
●There are two variations of transobturator midurethral sling procedures: inside-out (trocars are passed from a midurethral vaginal incision to exit through bilateral groin incisions) and outside-in (trocars are passed from bilateral groin incisions to exit through a midurethral vaginal incision). The evidence is insufficient to recommend the choice of one of these procedures rather than the other, and surgeons should use the procedure with which they are most comfortable. (See 'Choosing a type of transobturator sling' above.)
●Women who are planning primary midurethral transobturator sling placement should undergo preoperative evaluation to confirm the diagnosis of SUI, exclude other etiologies of urinary incontinence, and assess surgical risk. (See 'Preoperative evaluation and preparation' above and "Surgical management of stress urinary incontinence in females: Preoperative evaluation for a primary procedure".)
●We recommend antibiotic prophylaxis for surgical site infection for midurethral sling placement (Grade 1B). (See "Surgical management of stress urinary incontinence in females: Retropubic midurethral slings", section on 'Antibiotic prophylaxis'.)
●We suggest use of local anesthesia with conscious sedation or regional anesthesia rather than general anesthesia for midurethral sling placement (Grade 2C). General anesthesia may be used if it is strongly preferred by the patient or if it is required for a concomitant procedure. (See 'Preoperative evaluation and preparation' above and "Surgical management of stress urinary incontinence in females: Retropubic midurethral slings", section on 'Anesthesia'.)
●Common complications of midurethral transobturator sling placement include voiding dysfunction, mesh erosion, or groin pain. (See 'Complications' above.)
●Voiding dysfunction following sling placement may be treated initially with bladder catheterization. Persistent symptoms may require sling loosening or sling release, which may result in recurrent SUI. (See "Surgical management of stress urinary incontinence in females: Retropubic midurethral slings", section on 'Postoperative catheter management' and "Surgical management of stress urinary incontinence in females: Retropubic midurethral slings", section on 'Loosening'.)
●Long-term data show an SUI cure rate of approximately 73 percent following transobturator midurethral sling placement and long-term overall reoperation rates of 5.6 percent. (See 'Outcome' above.)
