Urogynaecology and pelvic floor problems
Helen Bickerstaff, Louise C Kenny in Gynaecology, 2017
Uterovaginal prolapse is caused by failure of the interaction between the levator ani muscles and the ligaments and fascia that support the pelvic organs. For a detailed description of the relationships and function of these structures, see the review by Wei & De Lancey in Further reading. The levator ani muscles are puborectalis, pubococcygeus and iliococcygeus. They are attached on each side of the pelvic side wall from the pubic ramus anteriorly (pubococcygeus), over the obturator internus fascia to the ischial spine to form a bowl-shaped muscle filling the pelvic outlet and supporting the pelvic organs (see Chapter 1, The development and anatomy of the female sexual organs and pelvis). There is a gap between the fibres of the puborectalis on each side to allow passage of the urethra, vagina and rectum, called the urogenital hiatus. The levator muscles support the pelvic organs and prevent excessive loading of the ligaments and fascia.
Biofeedback, Relaxation Training, and Cognitive Behavior Modification
Kevin W. Olden in Handbook of Functional Gastrointestinal Disorders, 2020
Proctalgia fugax is an idiopathic disorder characterized by recurring attacks of fleeting, intense anorectal pain. These attacks occur at irregular intervals—typically less than six times per year—and last several seconds to 20 minutes before ending (44). Some authors consider the disorder a variant of levator ani syndrome (45). Common precipitators are flatus or defecation for roughly a third of patients and sexual intercourse for 6% (45). Prevalence rates of 13.6% (2) to 18.4% (46) have been reported in healthy adults. The condition is approximately twice as common in females as in males, according to one survey (2) and is rarely reported before puberty (45). Among 148 clinic patients presenting with GI complaints, a 33% prevalence was found, with women outnumbering men by more than three times (51% to 12%) (47).
Fecal incontinence
Miranda A. Farage, Howard I. Maibach in The Vulva, 2017
The levator ani muscles are thought of as the pelvic diaphragm and consist of three individual muscles: the puborectalis, the iliococcygeal, and the pubococcygeal. Combined, the pelvic diaphragm encompasses a thin and broad muscle that attaches to the posterior pubic rami bilaterally and to the inner surface of the ischium posteriorly. The levator ani serves to support the pelvic viscera. The puborectalis is controlled by the somatic nervous system and serves as a major contributor to the anatomic angle that creates a barrier when at rest, and when contracted straightens out the rectum, allowing defecation. It attaches to the posterior pubic rami, then wraps posteriorly around the rectum and reinserts on the pubic rami, creating a sling (8).
Pelvic floor dysfunction in midlife women
Published in Climacteric, 2019
S. L. Johnston
Pelvic floor integrity is maintained by the coordinated actions of muscles (levator ani, urethral and anal sphincters), nerves (sacral plexus and pudendal nerve), and connective tissue (endopelvic ‘fascia’, perineal body, uterosacral and cardinal ‘ligaments’) anchored to the bony pelvis. The levator ani muscles close the urogenital hiatus, providing support by preventing protrusion of organs through that aperture. The fused posterior component of the muscles (the levator plate) offers a hammock-like support for the pelvic organs, preventing stretch and tension on the supportive connective tissue10. Endopelvic connective tissue provides additional visceral support, and is particularly important in maintaining it when the levators are weak. In the context of levator weakness, chronic tension can lead to fascial attenuation and structural failure. The levator ani muscles and endopelvic connective tissue therefore work together to provide normal pelvic support and urinary continence11. The quality of both muscle and collagen is integral to its ability to provide this dynamic support. Blood flow is essential for fibromuscular and neuromuscular tissue health, and vascularity is compromised by estrogen deficiency. It seems logical to conclude that menopause would negatively affect the pelvic floor and lead to dysfunction, especially over time and especially in the context of overall tissue aging.
Keeping the pelvic floor healthy
Published in Climacteric, 2019
C. Dumoulin, L. Pazzoto Cacciari, J. Mercier
The PFMs form a diaphragm that spans the entire pelvic cavity and provide support for the pelvic organs1. They comprise the coccygeus and the levator ani muscles with their five parts: the pubovaginal, puboperineal, and puboanal portions, which form the pubovisceral complex, and the puborectalis and iliococcygeus muscles6. These parts of the levator ani muscle form three different regions of the pelvic floor, from anterior to posterior:The pubovisceral muscle consists of muscle fibers that arise from the pubic bone on either side of the symphysis and attach to the walls of the pelvic organs and the perineal body; these help to close the urogenital hiatus.The puborectal muscle forms a sling around and behind the rectum, just cephalad to the external anal sphincter.The iliococcygeal muscle forms a relatively flat, horizontal shelf spanning the potential gap from one pelvic sidewall to the other near the sacrum6.
Female genito-pelvic reflexes: an overview
Published in Sexual and Relationship Therapy, 2019
Symen K. Spoelstra, Esther R. Nijhuis, Willibrord C. M. Weijmar Schultz, Janniko R. Georgiadis
The main somatic nerve of the perineum is the pudendal nerve, which has somatosensory and somatomotor tributaries, and which divides into three main branches (inferior rectal, perineal, dorsal penile/clitoral) at the level of the levator ani muscle. The muscles that embryonically derive from the cloacal sphincter (external anal and urethral sphincter, superficial transverse perineal muscle, bulbocavernosus muscle and ischiocavernosus muscle) are all innervated by pudendal nerve fibres originating in a specialized sacral motor neuronal pool called Onuf's nucleus (Iwata, Inoue, & Mannen, 1993; Onuf, 1899). As Onuf motoneurons innervate striated muscles but also are known to be relatively unaffected by somatic motoneuron diseases like amyotrophic lateral sclerosis (Mannen, Iwata, Toyokura, & Nagashima, 1977), they have been proposed to be of a mixed somatic/autonomic type (Kihira, Yoshida, Yoshimasu, Wakayama, & Yase, 1997). Interestingly, the pudendal nerve seems less involved in the innervation of the levator ani muscle. A separate nerve, the “levator ani nerve” (Wallner, Maas, Dabhoiwala, Lamers, & De Ruiter, 2010), arising from the ventral ramus of the third and fourth sacral nerves, is held to innervate the pelvic diaphragm. In at least 50% of cadavers studied, the pudendal nerve also contributed to innervation of the levator ani muscle, especially in regards to the medial portions (puborectal and pubococcygeal muscles) (Rock JA, 2003).
Related Knowledge Centers
- Coccygeus Muscle
- Ischium
- Muscle
- Pelvic Floor
- Vaginismus
- Pelvic Cavity
- Hip Bone
- Pelvis
- Orgasm
- Tendinous Arch of Pelvic Fascia