The pelvic floor is a combination of multiple muscles with ligamentous attachments creating a dome-shaped diaphragm across the boney pelvic outlet. This complex of muscles spans from the pubis (anterior) to the sacrum/coccyx (posterior) and bilateral to the ischial tuberosities. The bulk of the pelvic musculature is the levator ani, composed of the puborectalis, pubococcygeus, and iliococcygeus. The puborectalis wraps as a sling around the anorectal junction accentuating the anorectal angle during contraction and is a primary contributor to fecal continence. Elevation and support of the pelvic organs are associated with the pubococcygeus and the iliococcygeus. The pubococcygeus is the most medial component which separates, fashioning the levator hiatus with openings for the urethra, vagina (females), and anus. The bulbospongiosus and ischiocavernosus muscles are the primary contributors to the superficial portion of the anterior pelvic floor. The more superficial musculature of the posterior pelvic floor constitutes the external anal sphincter. The transverse perineal muscles cross the mid-portion of the superficial aspect of the pelvic floor and coalesce with the bulbospongiosus muscles and external anal sphincter as the perineal body.
Pelvic floor dysfunction (PFD) refers to a broad constellation of symptoms and anatomic changes related to abnormal function of the pelvic floor musculature. The disordered function corresponds to either increase activity (hypertonicity) or diminished activity (hypotonicity) or inappropriate coordination of the pelvic floor muscles. Alterations regarding the support of pelvic organs are included in the discussion of PFD and are known as Pelvic Organ Prolapse (POP). The clinical aspects of PFD can be urologic, gynecologic, or colorectal and are often interrelated. Another way to compartmentalize the concerns are anterior- urethra/bladder, middle- vagina/uterus and posterior- anus/rectum.
To assess the degree of dysfunction, three measurements must be taken into account. First, an anatomic landmark known as the pubococcygeal line must be determined, which is a straight line connecting the inferior margin of the pubic symphysis at the midline with the junction of the first and second coccygeal elements on a sagittal image. After this, the location of the puborectalis muscle sling is assessed, and a perpendicular line between the pubococcygeal line and muscle sling is drawn. This provides a measurement of pelvic floor descent, with descent greater than 2 cm being considered mild, and 6 cm being considered severe. Lastly, a line from the pubic symphysis to the puborectalis muscle sling is drawn, which is a measurement of the pelvic floor hiatus. Measurements of greater than 6 cm are considered mild, and greater than 10 cm severe. The degree of organ prolapse is assessed relative to the hiatus. The grading of organ prolapse relative to the hiatus is more strict, with any descent being considered abnormal, and greater than 4 cm being considered severe.
By definition, postpartum pelvic floor dysfunction only affects women who have given birth, though pregnancy rather than birth or birth method is thought to be the cause. A study of 184 first-time mothers who delivered by Caesarean section and 100 who delivered vaginally found that there was no significant difference in the prevalence of symptoms 10 months following delivery, suggesting that pregnancy is the cause of incontinence for many women irrespective of their mode of delivery. The study also suggested that the changes which occur to the properties of collagen and other connective tissues during pregnancy may affect pelvic floor function.
Many people with interstitial cystitis (IC) have problems with the group of muscles in the lower pelvic area and develop a condition called pelvic floor dysfunction (PFD). If you have IC and a poor urine stream, feel the need to push or bear down to urinate, and have painful intercourse, you may have PFD. Treating PFD may be very helpful in reducing symptoms and pain for some IC patients—most patients see improvement after several weeks of therapy.
Mechanistically, the causes of pelvic floor dysfunction are two-fold: widening of the pelvic floor hiatus and descent of pelvic floor below the pubococcygeal line, with specific organ prolapse graded relative to the hiatus. Associations include obesity, menopause, pregnancy and childbirth. Some women may be more likely to developing pelvic floor dysfunction because of an inherited deficiency in their collagen type. Some women may have congenitally weak connective tissue and fascia and are therefore at risk of stress urinary incontinence and pelvic organ prolapse.
If you think of the pelvis as being the home to organs like the bladder, uterus (or prostate in men) and rectum, the pelvic floor muscles are the home’s foundation. These muscles act as the support structure keeping everything in place within your body. Your pelvic floor muscles add support to several of your organs by wrapping around your pelvic bone. Some of these muscles add more stability by forming a sling around the rectum.
Ultrasound uses high-frequency sound waves applied through a wand or probe on your skin to produce an internal image or to help treat pain. Real-time ultrasound can let you see your pelvic floor muscles functioning and help you learn to relax them. Therapeutic ultrasound uses sound waves to produce deep warmth that may help reduce spasm and increase blood flow or, on a nonthermal setting, may promote healing and reduce inflammation.
Electrical stimulation uses a small probe inserted into the vagina or rectum to stimulate your pelvic floor muscles, helping desensitize nerves and causing muscles to contract and relax. Stimulation through electrodes placed on your body may calm pain and spasms. Different kinds of electrical stimulation devices are available for home use, both for internal stimulation with a probe or for external stimulation, such as a transcutaneous electrical nerve stimulation (TENS) or similar unit, to ease pain.