Int Urogynecol J (2008) 19:35–40 DOI 10.1007/s00192-007-0475-9
CONTROVERSIES IN UROGYNECOLOGY
The Integral Theory of continence Peter E. P. Petros & Patrick J. Woodman
Received: 3 September 2007 / Accepted: 7 September 2007 / Published online: 30 October 2007 # International Urogynecology Journal 2007
The Integral Theory of incontinence: Editor’s introduction Steven Swift e-mail: swifts@musc.edu The Integral Theory was originally met with a great deal of skepticism, that is, until the tension-free vaginal tape (TVT) was introduced. This remarkably successful technology was born out of the observations from this theory. Following the success of the TVT, skeptics became fewer and fewer and the tenets of the Integral Theory became accepted as truth. However, this has also had a deleterious effect, hampering research into the other aspects of the Integral Theory. As often happens, once something is “understood and verified” it is inviolate and research slows down or stops.
We, researchers into pelvic floor disorders, have failed in our fiduciary responsibility to study and prove or disprove the various observations that have been proposed by the Integral Theory. The two commentaries that follow will hopefully serve to re-invigorate discussion and investigations into the Integral Theory of incontinence. Professor Petros provides an excellent short description of the Integral Theory and how various pelvic floor disorders are explained by this theory. Dr Woodman’s commentary serves as a reality check into what we can and cannot attribute to the various tenets of the Integral Theory. One thing that comes through in both is that we need more research in this area. We should not fall back on the success of the TVT but should look forward at this theory to help us improve our treatment of other pelvic floor disorders.
For: Peter E. P. Petros Controversies in Urogynecology Articles published in this category present the pro and contra positions on a topic in our specialty. The experts arguing each position are listed jointly as authors of the whole article and separately as authors of their respective positions. P. E. P. Petros (*) Royal Perth Hospital, 14A Osborne Pde, Claremont, Perth, Western Australia 6010, Australia e-mail: kvinno@highway1.com.au P. E. P. Petros University of Western Australia, Perth, Australia P. J. Woodman Female Pelvic Medicine & Reconstructive Surgery, Department of Obstetrics and Gynecology, Indiana University School of Medicine, 1633 N. Capitol Ave. #436, Indianapolis, IN 46240, USA e-mail: Patrick.Woodman@gmail.com
e-mail: kvinno@highway1.com.au
The Integral Theory The Integral Theory states that pelvic organ prolapse and abnormal pelvic symptoms are mainly caused by connective tissue laxity in the vagina or its supporting ligaments [1]. The Integral Theory system has four components, function [2], dysfunction [2], diagnosis [3], and minimally invasive day surgery [4]. Normal structure The three pelvic organs, bladder, vagina, and rectum, are suspended from the pelvic brim by three suspensory
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Normal function The urethra and anus are essentially emptying tubes, and the bladder and rectum are receptacles. The rectum and anus are mechanically closed or opened by external muscle forces (arrows, Fig. 1). The nervous system signals fullness and acts as a “motor” to accelerate opening (micturition, defecation) or closure (continence). Urethral closure The forward muscle force (arrows, Fig. 1) stretches the vagina forwards against the pubourethral ligament (PUL) to close the urethra from behind. The backward forces (arrows, Fig. 1) stretch the upper vagina and bladder base backwards and downwards in a plane around the PUL to close off the proximal urethra. Urethral opening (micturition) The forward-force PCM relaxes. The backward muscle forces (arrows) stretch the proximal vagina (PCF, Fig. 1) to open out the posterior urethral wall (broken lines). The bladder contracts and urine is expelled. The micturition reflex coordinates and accelerates this emptying process [5]. Anorectal closure
Fig. 1 The pictorial diagnostic algorithm summarizes the relationships between structural damage in the three zones and urinary and fecal symptoms. The size of the bar gives an approximate indication of the prevalence (probability) of the symptom. The same connective tissue structures in each zone (red lettering) may cause prolapse and abnormal symptoms. Arrows represent directional muscle forces. Anterior zone: external urethral meatus to bladder neck; middle zone: bladder neck to cervix; posterior zone: vaginal apex, posterior vaginal wall, and perineal body. R = rectum; RVF = rectovaginal fascia; PB = perineal body; PRM = m.puborectalis; LP = m.levator plate; LMA = m. longitudinal muscle of the anus; PCM = m.pubococcygeus; PUL = pubourethral ligament; USL = uterosacral ligament; CL = cardinal ligament; PCF = pubocervical fascia; CL-Cx ring = cardinal/cervical ring complex; ATFP = arcus tendineus fascia pelvis; EAS = external anal sphincter; N = bladder base stretch receptors
ligaments, pubourethral (PUL), cardinal/uterosacral, and arcus tendineus fascia pelvis (Fig. 1). The vaginal fascia is closely linked to the suspensory ligaments and perineal body. Collagen is their main structural component. Three directional muscle forces (arrows, Fig. 1) tension the organs to give them position, shape, and strength.
The puborectalis muscle (PRM) contracts forwards to close off the anus from behind. The backward/downward forces (arrows, Fig. 1) stretch the rectum backwards around the PRM forming the anorectal angle and closing the rectum [2]. Anorectal opening (defecation) With anorectal opening, the PRM relaxes. The backward muscle forces pull open the posterior anorectal wall (broken lines, Fig. 1), the rectum contracts, and feces are expelled. The defecation reflex coordinates and accelerates this emptying process [2]. Dysfunction Damaged collagen/elastin in the suspensory ligaments or their connecting fascia may cause organ prolapse, cystocele, rectocele, and abnormal symptoms (Fig. 1) There are three zones of connective tissue laxity and three main structures in each zone (Fig. 1). The pathogenesis of abnormal symptoms A muscle requires a firm insertion point to function optimally. All three directional muscle forces (arrows,
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Fig. 1) act against suspensory ligaments: the forward force against the PUL, the backward force against the PUL and the perineal body, and the downward force against the uterosacral ligament. If these ligaments are lax, the muscle can neither open nor close the urethral or anal tubes. This explains the paradoxical coexistence of incontinence and abnormal emptying in both the bladder and the rectum [2]. These are mechanical symptoms and are zone-specific. Urge, frequency, nocturia, and pelvic pain are neurogenic symptoms and can occur with minimal prolapse: like a trampoline, the muscle forces stretch the vaginal membrane against the ligaments (springs) to support the micturition stretch receptors “N” (Fig. 1). A lax membrane may cause “N” to fire off prematurely [6]. This is perceived by the cortex as urgency, frequency, and nocturia. Like a trampoline, even one loose spring (ligament) may prevent membrane tightening. It follows that laxity in any of the three zones may cause such symptoms.
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Fig. 2 Surgical repair of damaged ligaments. Polypropylene tapes (T) (in this case with attached soft tissue anchors) may be used to reinforce the three main suspensory ligaments, pubourethral (PUL), uterosacral (USL), cardinal (CL), and arcus tendineus fascia pelvis (ATFP)
Diagnosis Specific symptoms indicate three zones of damage (Fig. 1). Vaginal examination confirms the degree of prolapse in each zone. The anatomy precludes significant prolapse in the anterior zone. The only way to diagnose PUL defect (Fig. 1) is to ask the patient to cough and apply unilateral pressure to the midurethral part of the vagina (“simulated operation”). “Simulated operations” Simulated operations [3] support lax structures and are a direct test of the theory. Pressure is applied digitally or with a hemostat to specific connective tissue structures in each of the three zones of the vagina. Normally, it is used clinically to assess the origin of stress and urgency symptoms. However, it has been used to assess the contribution of a particular connective tissue structure to urethral pressure [7] and urethrovesical morphology [8]. This technique can be used introperatively to assess whether cystocele is caused by a central, paravaginal, or cervical ring (transverse) defect [4]. For the latter, Allis forceps are applied over the laterally displaced cardinal ligaments and approximated medially. This maneuver can be performed on the laterally displaced uterosacral ligaments, and also on the perineal body. Urodynamics Changes observed in urethral pressure [7], and even unstable detrusor patterns [9], following support of specific connective tissue structures during urodynamic studies indicate these may be secondary manifestations of connective tissue defects. Cough transmission ratio was found to
be a more sensitive measure of anterior zone laxity [7] than transperineal ultrasound. Total emptying time, a “start and stop” urodynamic urination pattern, and raised residual volume indicate middle or posterior zone laxity [2]. Surgery Surgery is minimal and usually day-care [4, 10]. The firstgeneration “tension-free” polypropylene tapes have been applied at midurethra (anterior zone, Figs. 1 and 2), for cure of stress incontinence, to the vaginal apex (posterior zone; Figs. 1 and 2), for cure of uterine/vault prolapse. Reinforcement of muscle insertion points (ligaments) restores the opening and closing muscle forces and, therefore, function. Up to 80% improvement rate in the algorithm symptoms (Fig. 1) has been reported [10–12]. Recently, large meshes attached to “tension-free” anterior and posterior tapes have been used to cure large cystocele and rectocele. Problems of dyspareunia, erosion, and even fistula have brought some controversy to this treatment. Because of these concerns, the author has applied, over the past 3 years, a second-generation technique that is sitespecific and uses far less mesh (Fig. 2). The same structural engineering principle used for domestic ceiling construction is applied. An 8-mm-wide mesh tape attached to two anchors is placed in the exact position of the damaged ligaments and tightened precisely. The tape acts like a ceiling beam to support the vagina, the vagina being analogous to a plaster board (Fig. 2). Whereas a large mesh sheet may limit posterior stretching, a transverse tape does not [14]. The mesh tape is attached superiorly by a soft tissue anchor (Fig. 2), greatly diminishing the surfacing of the tape, a major cause of erosion.
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Discussion Even today, many physicians base their management of urinary incontinence on the 1988 recommendations [13] of the International Continence Society (ICS). In 1988, the ICS stated that symptoms are unreliable and that unstable bladder symptoms are not surgically curable and require drug therapy. Only patients with “genuine stress incontinence” were considered surgically curable, and patients with “mixed” incontinence, stress and urge, should not be operated on. Rather, anticholinergic therapy was recommended. Though not apparently extant in their more recent 2002 pronouncements, the ICS has done nothing to dispel such previous recommendations. Drug therapy, with all its side-effects and noncompliance, is still the recommended treatment of choice for such conditions by authors of the last (2002) report [14], as evidenced by their writings. Surgery [4] is never mentioned as an option. In contrast, the Integral Theory system regards abnormal urodynamic findings and symptoms as secondary manifestations of connective tissue damage. “Repair the structure, and you will restore the function.” Because of their neurological component, some symptoms such as urgency, nocturia, and pelvic pain may occur with minor prolapse. This may appear controversial to some readers, but observation of symptom improvement [10–12] following posterior sling repair indicates these symptoms can be surgically addressed. Influence of dynamic anatomy observations on surgical practice Video X-ray studies [5] confirm that the organs move independently of each other and are stretched in opposite directions during opening and closure of the urethra and anorectum and, indeed, during sexual intercourse. These movements are facilitated by vesicovaginal and rectovaginal spaces. Discrete site-specific tapes (Fig. 2) do not interfere with these movements. Use of large mesh may eliminate the organ spaces and “glue” the vagina to rectum or bladder. The scar tissue created by large mesh shrinks considerably with time, so that a mesh applied between the perineal body and the uterosacral ligaments, for instance, could prevent the backward stretching of the vaginal membrane required to support the stretch receptors “N,” a key factor in controlling urgency and nocturia [9]. Conclusion The theory has expanded considerably since its first publication in 1990 and, with it, the requirement for scientific proof of its components. The validation spectrum to date is wide. For some parts of the theory, for example, stress incontinence, the level of scientific validation
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achieved has been high; for others, such as fecal incontinence and pelvic pain, there has been little besides clinical observation. It has always been the hope of the author, and indeed, the coauthor, the late Professor Ulmsten, that the theory should not be a mental block for physicians, rather an invitation to join a new direction in pelvic floor research and practice.
Against: Patrick J. Woodman
e-mail: Patrick.Woodman@gmail.com
The Integral Theory of pelvic floor dysfunction: clinical controversy or factual paradigm I would like to start by recognizing the considerable contributions of my esteemed colleague in the field of urogynecology. The Integral Theory is intuitive, simple, and logically sound. In fact, Dr. Petros’ analogy of a suspension bridge was one of the first I used to counsel my patients about pelvic organ support. It only makes sense that, if the pelvic organs are neuromuscularly intact, replacing the organs into their usual position should allow for normal pelvic floor function. Additionally, minimizing dissection should prevent further neuromuscular deterioration [1]. In addition, when a structure or organ has been removed, the Integral Theory supports compensating for its absence. For example, during a hysterectomy, the Integral Theory suggests that the cardinal–uterosacral pedicles be approximated in the midline to pull the slack out of the ligament complex and to resuspend the vaginal cuff [2]. This makes sense clinically, and it is comforting that our standard of care is supported by an established theory; however, the benefits of this surgical practice have never been established by a prospective trial, and this is the Achille’s heel of the Integral Theory (there is very little data to support its assertions). Integral Theory proponents criticize the International Continence Society-sponsored Standardization Committee for recommending therapies that do not employ the principles of the Integral Theory [4]. In particular, they assert that surgical principles of the Integral Theory should be employed when treating overactive bladder or urgeassociated incontinence (one of the more controversial tenets of the theory). There is some debate on the relative efficacy of medical management of the overactive bladder, but antichoinergic medications have been rigorously studied in both the basic science arena and in large prospective randomized trials. There is basic scientific evidence that cholinergic receptors are present in the detrusor muscle and
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that anticholinergic agents can block these receptors, and, in clinical trials, they have demonstrated efficacy beyond placebo. The same cannot be said regarding the assertions of the Integral Theory that suggest supporting the midurethra (the anterior vaginal wall along the arcus tendineous, and the vaginal cuff along the uterosacral “neoligament”) will prevent stretching of the anterior vaginal wall, which will in turn “cure” overactive bladder and/or urge incontinence symptoms. This is based on the existence of “hypothesized stretch receptors” and the idea of “point N” or the zone of critical elasticity at the proximal urethra and bladder neck [3]. Although plausible, even logical, the presence of stretch receptors that uniformly lead to irritative voiding symptoms has never been confirmed. Proponents of the theory cite data suggesting a 50–60% resolution of urge incontinence and overactive bladder symptoms in women with mixed incontinence who undergo a tensionfree vaginal tape (TVT) sling, which leaves a 40–50% persistence rate and a 9–15% de novo irritative voiding symptom rate [5]. The additional anecdotal “disappearance” of urge by supporting the bladder base with a full bladder or with a Kegel contraction, while interesting, does not supplant real evidence-based medicine confirming this aspect of the Integral Theory. The Integral Theory is an excellent compilation of previous work by researchers like Denny-Brown, Shafik, and DeLancey; much of the support for the Integral Theory itself is based on observational evidence or expert opinion. Dr. Petros admits that the Integral Theory evolved from early observations of the intravaginal slingplasty (IVS) [6], followed up by publications citing small case series with no quantifiable follow-up [7, 8]. Hampered by the challenges all clinical researches face, the Integral Theory data are based upon small numbers; retrospective or poorly controlled prospective study designs; and, where data is lacking, pure speculation. Dr. Petros is certainly a noted expert; however, most citations listed in the very few research articles on the Integral Theory cite these early articles or Dr. Petros’ own book on the subject [9]. These observations, while very interesting, have not been subjected to study using the scientific method to prove or disprove their accuracy. The Integral Theory has had it successes and it led directly to the development of the TVT sling (one of the biggest advances ever in pelvic reconstructive surgery). In contrast, it also led to the development of the posterior IVS [10]. The posterior IVS has fared worse then the TVT: disappointing success rates, numerous complications, and no long-term surgical outcome data [6, 11–16]. In the 17 years since its first publication, it is interesting that the scientific method has not been used to verify the many assertions of the Integral Theory. Since the Integral Theory started as an observational surgical study that led to the
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very successful TVT, it is even more surprising that large, prospective, long-term surgical outcome studies have not been published by its supporters. One last issue the Integral Theory certainly brings to mind is the large amount of non-peer-reviewed selfpromotion. The Integral Theory is promoted in media vehicles such as books [9], journals (Pelviperineology), websites http://www.integraltheory.org), and professional groups based on the Integral Theory, such as the Australian Association of Vaginal and Incontinence Surgeons. Although new data from research studies based on a scientific idea or theory is welcomed by most peer-reviewed journals, many articles on the Integral Theory seem to restate the same ideas, rereport the same data, and cross-reference each other in citations. As tempting as it may be to have an all-encompassing paradigm to explain everything we urogynecologists do, the evidence-based medicine supporting the Intergral Theory as an all-encompassing explanation for pelvic floor dysfunction is lacking. The Integral Theory makes predictions but scientific progress can never stand still. Its assertions must be proven, then further theories proposed. Pelvic floor dysfunction is complicated and, although the Integral Theory is a compromise between those who believe in reconstruction and those who believe in compensation, I cannot blindly follow one belief system that is not supported by rigorous, scientific proof. I look forward to seeing further studies into the mechanics of the Integral Theory and hope that one day there is a simple allencompassing set of guidelines that guide us in good clinical practice. Only time will tell if the Integral Theory fills that void.
References For 1. Petros PE (2006) Chapter 1, overview. In: Petros PE (ed) The female pelvic floor—function, dysfunction and management according to the integral theory, 2nd edn. Springer, Berlin Heidelberg New York, pp 1–12 2. Petros PE (2006) The anatomy and dynamics of pelvic floor function and dysfunction. In: Petros PE (ed) The female pelvic floor—function, dysfunction and management according to the integral theory, 2nd edn. Springer, Berlin Heidelberg New York, pp 13–50 3. Petros PE (2006) Diagnosis of connective tissue damage. In: Petros PE (ed) The female pelvic floor—function, dysfunction and management according to the integral theory, 2nd edn. Springer, Berlin Heidelberg New York, pp 51–82 4. Petros PE (2006) Reconstructive pelvic floor surgery according to the integral theory. In: Petros PE (ed) The female pelvic floor— function, dysfunction and management according to the integral theory, 2nd edn. Springer, Berlin Heidelberg New York, pp 83– 167
40 5. Petros PE, Ulmsten U (1997) Role of the pelvic floor in bladder neck opening and closure: I muscle forces; II vagina. Int Urogynecol J Pelvic Floor Dysfunct 8:69–80 6. Petros PE, Ulmsten U (1993) Bladder instability in women: a premature activation of the micturition reflex. Neurourol Urodyn 12:235–239 7. Petros PE (2003) Changes in bladder neck geometry and closure pressure following midurethral anchoring suggest a musculoelastic mechanism activates closure. Neurourol Urodyn 22:191–197 8. Petros PE, Von Konsky B (1999) Anchoring the midurethra restores bladder neck anatomy and continence. Lancet 354:9193:997–998 9. Petros PE (1999) Detrusor instability and low compliance may represent different levels of disturbance in peripheral feedback control of the micturition reflex. Neurourol Urodyn 18:81–91 10. Petros PE (1997) New ambulatory surgical methods using an anatomical classification of urinary dysfunction improve stress, urge, and abnormal emptying. Int Urogynecol J Pelvic Floor Dysfunct 8(5):270–278 11. Neuman M, Lavy Y (2007) Posterior intra-vaginal slingplasty for the treatment of vaginal apex prolapse: medium-term results of 140 operations with a novel procedure. Eur J Obstet Gynecol Reprod Biol (in press) DOI 10.1016/j.ejogrb.2006.07.035 12. Farnsworth BN (2002) Posterior intravaginal slingplasty (infracoccygeal sacropexy) for severe posthysterectomy vaginal vault prolapse, a preliminary report on efficacy and safety. Int Urogynecol J Pelvic Floor Dysfunct 13:4–8 13. Abrams P, Blaivas J, Stanton SL, Andersen JT (1988) International continence society committee on the standardization of terminology of lower urinary tract function. Scand J Urol Nephrol Suppl 114:1–19 14. Abrams P, Cardozo L, Fall M, Griffiths G, Rosier P, Ulmsten U, van Kerrebroeck P, Victor A, Wein A (2002) The standardization of terminology of lower urinary tract function: report from the Standardisation Subcommittee of the International Continence Society. Neurourol Urodyn 21:167–178
Against 1. Benson JT, Lucente V, McClelland M (1996) Vaginal versus abdominal reconstructive surgery for the treatment of pelvic support defects: A randomized study with long-term outcome evaluation. Am J Obstet Gynecol 175(6):1418–1422 2. Petros PEP (2001) Vault prolapse I: dynamic supports of the vagina. Int Urogynecol J Pelvic Floor Dysfunct 12:292–295 3. Petros PEP, Ulmsten UI (1990) An integral theory of female incontinence: experimental and clinical considerations. Acta Obstet Gynecol Scand 69(Suppl 153):7–31
Int Urogynecol J (2008) 19:35–40 4. Abrams P, Blaivas J, Stanton SI, Andersen JT (1988) International Continence Society Committee on the standardization of terminology of lower urinary tract function. Scand J Urol Nephrol Suppl 114:1–19 5. Segal JL, Vassallo B, Kleeman S, Silva WA, Karram MM (2004) Prevalence of persistent and de novo overactive bladder symptoms after the tension-free vaginal tape. Obstet Gynecol 104: 1263–1269 6. Petros P (2007) The International Continence Society and Integral Theory. Systems for management of the incontinent female. A comparative analysis. Pelviperineol 26:25–29 7. Petros PEP, Ulmsten UI (1990) An integral theory of female incontinence: experimental and clinical considerations. Acta Obstet Gynecol Scand 69(Suppl 153):7–31 8. Petros PEP, Ulmsten UI (1993) An integral theory and its method for the diagnosis and management of female urinary incontinence. Scand J Urol Nephrol Suppl 153:3–93 9. Petros PEP (2007) The female pelvic floor: function, dysfunction, and management according to the integral theory. Springer, Berlin Heidelberg New York, pp 1–222 10. Petros PEP (2001) Vault prolapse II: restoration of dynamic vaginal supports by infaracoccygeal sacropexy, an axial day-case vaginal procedure. Int Urogynecol J Pelvic Floor Dysfunct 12: 296–303 11. Meschia M, Pifarotti P, Bernasconi F, Magatti F, Vigano R, Bertozzi R, Barbacini P (2006) Tension-free vaginal tape (TVT) and intravaginal slingplasty (IVS) for stress incontinence: a multicenter randomized trial. Am J Obstet Gynecol 195:1338–1342 12. Baessler K, Hewson AD, Tunn R, Schuessler B, Maher CF (2005) Severe mesh complications following intravaginal slingplasty. Obstet Gynecol 106:713–716 13. Vardy MD, Brodman M, Dorchak JM, Dietrich ML, Olivera C, Blumenstock E, Bercik RS, Zhou H, Shobeiri SA, Finklestein K, Naughton MJ, Dunn JS, Clary BB, Flisser AJ, Francis S, Zimmerman C, Porter W (2006) Anterior IVS Tunneller device for stress incontinence and posterior IVS for apical vault prolapse— a two-year prospective multicenter study. Int Urogynecol J Pelvic Floor Dysfunct 17(Suppl 3):S400–S401 14. Luck M, Steele A, Leong F, McLennan MT (2006) Efficacy and complications of intravaginal slingplasty. Int Urogynecol J Pelvic Floor Dysfunct 17(Suppl 3):S403 15. Moore S, Mattox F (2005) Posterior vaginal sling experience in elderly patients yields poor results. J Pelvic Med Surg 11 (Suppl 1):S4 16. DeVita D, Santinelli G, Greco E, Docimo G, Schiavo M, Sirimarco F, Docimo L, D’Armiento M (2004) Conservative treatment of II and III degree utero-vaginal prolapse with transobturator suspension of bladder and uterus and with posterior IVS (triple-operation for prolapse using prosthesis). ICS/IUGA Video Abstract #347