The integral theory of female stress urinary incontinence is not scientifically sound

Abstract

The integral theory of female stress urinary incontinence is not scientifically soundDear Editor, Tension-free vaginal tape (TVT) surgery for stress urinary incontinence (SUI) has an overall failure rate of 10-20%. However, the failure rate is much higher for women with hypomobile SUI, and many women who are cured of SUI have de novo or persistent symptoms of urgency and frequency. This suggests that a problem exists.The rationale for TVT surgery is based on the integral theory (IT). Although a correct theory should be able to discriminate between appropriate and inappropriate surgery, IT cannot do this. However, instead of confronting the problems with the theory, failures are blamed on the pathophysiology of SUI, which is alleged to be too multifactorial to be rectified by a single procedure. Therefore, the rationale for IT must be challenged.The abdominal cavity is a closed entity, and the intraabdominal pressure (Pabd) persistently affects all intraabdominal organs, including the bladder and the proximal two-thirds of the urethra. This is true for both continent and incontinent women, both at rest and during stress.The abdominal cavity is similar to a water bag. All but 10-15% of its content is incompressible water with some gas. As proposed by Enhörning's theory of direct abdominal pressure transmission, 1 a change in Pabd affects the whole cavity simultaneously. However, the expression, "pressure transmission," is inappropriate because no pressure wave travels in any direction.The originators of IT rejected Enhörning's theory. They observed that during straining, many continent women had urethras that hung very low without causing leakage of urine. They also stated that "eight patients with a bladder neck in a starting position at or below the lower border of the pubic symphysis were cured of SUI without elevation of the bladder neck, which invalidates Enhörning's pressure transmission theory." 2 However, this conclusion is incorrect. A very low bladder neck position means that the bladder neck is outside the bony pelvis, but is not outside the abdominal cavity, which is delimited by the endopelvic fascia.Enhörning's pressure transmission theory is incorrect regarding the lower limit of the abdominal cavity but is otherwise correct. Suggesting that Pabd does not fully affect the proximal urethra indicates that the proximal urethra is situated outside the abdominal cavity, and this is incorrect.The significance of pressure transmission during straining was investigated using a virtual operation (VO) technique, that is, the recreation of a competent pubourethral ligament by unilateral midurethral support. 3,4 The authors showed that an equivalent Pabd during straining had different effects on the proximal urethra, depending on the absence or presence of VO-support. Without VO support, there was decreased pressure, funneling, and leakage of urine but with VO support, increased pressure, no funneling, and no leakage of urine were observed.In this experiment, VO neither elevated nor obstructed the urethra, but ...

The urethral hanging theory and how it relates to Enhörning’s theory and the integral theory

“…The development of a new theory starts with an idea. The basic-and only-new idea relating to the urethral hanging theory (UHT) [1][2][3][4][5] is that, in the case of stress urinary incontinence (SUI), the proximal urethra descends to a hanging position on a less mobile bladder neck and is funneled. The rest of the theory builds on the works of others and the laws of physics.…”

More about the urethral hanging theory (UHT) and a response to Dr. Peter Petros’ comments

“…Enhörning's direct abdominal pressure transmission theory (ET), 19 is grounded on this pressure law although ET is not correct regarding the lower limit of the AC. 2 During straining, the pressure increases concurrently throughout the entire AC. The same pressure increase occurs around/inside the bladder and around/inside the proximal urethra.…”

“…F I G U R E 2 Abbreviations: UHT, urethral hangning theory; IT, integral theory; ET, Enhörnings theory; PUL, pubo-urethral ligaments; IVP, intravesical pressure; Pdet, detrusor pressure; MUP, maximum urethral pressure at rest; UP, urethral pressure; Pabd, intraabdominal pressure; Fs, shearing force; Fd, outflow distending force; KINK, kinking/stretching/narrowing of the proximal urethra against the PUL as a fulcrum; PCM, pubococcygeus muscles (lift the vaginal hammoch and press the posterior urethra wall against its anterior wall); RS, rhabdosphincteraccording to IT, both RS and PCM have reduced effect in cases of loose and lengthened PUL; GR, guarding reflexes (RS+PCM); * = Enhörning's pressure transmission theory is incorrect regarding the lower limit of the abdominal cavity but is otherwise correct. 2 The total number of women who undergo SUI surgery are constantly increasing. A failed operation, consumes the limited resources and is a misery for the woman.…”

“…This statement indicates a major misreading of the UHT. 2 A central principle of the UHT is that a closed miniscule meatus internus (m.i.) is a perfect seal that cannot be pushed open by the intravesical pressure (IVP).…”

“…The muscle actions that explain the open out the proximal urethra are the same muscle actions which generate the acutely high intra-abdominal pressure (Pabd) during stress. During normal micturition, the combined action of the inner longitudinal smooth muscles of the detrusor and urethra opens out the proximal urethra [2].…”