Abstract
The aim of the study was to examine the role of vaginal stretching during bladder neck opening and closure. The study group comprised 12 patients with GSI and 4 controls. The position of the bladder neck relative to the vagina was assessed in the resting, straining and ‘squeezing’ positions using video-radiological studies. Radio-opaque dye was instilled into the bladder, vagina, rectum and levator plate. Vascular clips applied to the midurethral, bladder neck and bladder base parts of the anterior vaginal wall assisted in determining differential movements of these parts of the vagina during bladder neck opening and closure. The suburethral vagina (hammock) was shown to stretch downwards and forwards during straining, and downwards and backwards during micturition. The bladder neck, upper part of the vagina and the rectum were stretched backwards and downwards in an identical manner during straining and micturition, apparently in response to backward contraction of the levator plate and downward angulation of its anterior lip. All organs were stretched upwards and forwards during ‘squeezing’. The findings support the hypothesis that, during stress and micturition, selective pelvic floor contractions stretch the vagina against intact pubourethral and uterosacral ligaments to assist opening and closure of the urethra and bladder neck.
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References
Krantz K. Anatomy and physiology of the vulva and vagina. In: Philipp EE, Barnes JB, Newton M, eds. Scientific foundations of obstetrics and gynaecology. London: Heinemann Medical, 1977:72–78
Petros PE, Ulmsten U. An integral theory of female urinary incontinence.Acta Obstet Gynecol Scand (1990) 69:1–79 (Suppl 153)
Petros PE, Ulmsten U. An integral theory and its method for the diagnosis and management of female urinary incontinence.Scand J Urol Nephrol 1993; (Suppl 153) 27:1–93
De Lancey. Structural support of the urethra as it relates to stress urinary incontinence: the hammock hypothesis.Am J Obstet Gynecol 1994;170:1713–1723
Enhorning G. Simultaneous recording of intravesical and intraurethral pressure.Acta Chir Scand 1961;27:61–68
Petros PE, Ulmsten U. Urethral pressure increase on effort originates from within the urethra, and continence from musculovaginal closure.Neurourol Urodyn 1995;14:337–350
Zacharin RF. A suspensory mechanism of the female urethra.J Anat 1963;97:423–427
Blaivas JG. The neurophysiology of micturition: a clinical study of 550 patients.J Urol 1982;127:958–962
Shafik A. The vesicocavernosus reflex: role in the act of micturition.Int Urogynecol J 1993;4:346–349
Christensen LL, Djurhuus JC, Constantinou CE. Imaging of pelvic floor contractions using MRI.Neurourol Urodyn 1995;14:209–216
Gray’s Anatomy, 31st edn. Johnson TB, Whillis J, (eds). London: Longmans Green, 1954.
Petros PE, Ulmsten U. Bladder instability in women: a premature activation of the micturition reflex.Neurourol Urodyn 1993;12:235–239
Petros PE. Symptoms of defective emptying and raised residual urine may arise from ligamentous laxity in the posterior vaginal fornix. ICS 1994, Prague, abstract 169, pp 158–159
Ulmsten U, Henriksson L, Johnson P, Varhos G. An ambulatory surgical procedure under local anesthesia for treatment of female urinary incontinence.Int Urogynecol J 1996;7:81–86
Petros PE. The intravaginal slingplasty operation, a minimally invasive technique for cure of urinary incontinence in the female.Aust NZ J Obstet Gynecol 1996;36:4:1–9
Yamada H. Mechanical properties of urogenital organs and tissues. In: Evans FG (ed) Strength of biological materials, Baltimore: Williams & Wilkins, 1970;205–218,272–280
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EDITORIAL COMMENT: The authors propose a new theory for the mechanism of micturition and continence. The new ‘Integral Theory’ describes the role of the vagina and three pelvic floor muscles, the levator plate, the anterior portion of the pubococcygeus (PCM) and the longitudinal muscles of the anus (LMA) in the opening and closing of the urethra. Unlike the ‘hammock hypothesis’, proposed by Delancey, the authors believe it is the forward movement of the vagina around its attachment to the pubourethral ligaments via contraction of the PCM that closes off the urethra, and not increased abdominal pressure transmission to the proximal urethra. Their proposed mechanism for incontinence is laxity of the vaginal hammock and decreased forward motion, and less compression of the urethra. This theory is also in contrast to Shafik’s ‘common sphincter’ concept of continence, which stresses the importance of the puborectalis and external urethral sphincter as the main mechanism for continence, with no significance given to the role of the anterior vaginal wall or its attachment and movement around the pubourethral ligament. This new integral theory is based on findings of muscle movements using cadaveric dissection, video X-ray studies, digital palpation, EMG and dynamic urethral pressure measurements. This is an interesting theory which again emphasizes the role of the pelvic floor muscles, not only in their support function but also in their role of active movements of the viscera within the bony pelvis.
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Papa Petros, P.E., Ulmsten, U. Role of the pelvic floor in Bladder neck opening and closure II: Vagina. Int Urogynecol J 8, 69–73 (1997). https://doi.org/10.1007/BF02764821
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DOI: https://doi.org/10.1007/BF02764821