As many as 50 percent of people with chronic constipation have pelvic floor dysfunction (PFD) — impaired relaxation and coordination of pelvic floor and abdominal muscles during evacuation. Straining, hard or thin stools, and a feeling of incomplete elimination are common signs and symptoms. But because slow transit constipation and functional constipation can overlap with PFD, some patients may also present with other signs and symptoms, such as a long time between bowel movements and abdominal pain.
When mechanical, anatomic, and disease- and diet-related causes of constipation have been ruled out, clinical suspicion should be raised to the possibility that PFD is causing or contributing to constipation. A focused history and digital examination are key components in diagnosing PFD. The diagnosis can be confirmed by anorectal manometry with balloon expulsion and, in some cases, traditional proctography or dynamic magnetic resonance imaging defecography to visualize pathologic pelvic floor motion, sphincter anatomy and greater detail of surrounding structures.
Currently there is no surefire way to distinguish PFD from IC, and oftentimes patients have both conditions. Some healthcare providers examine pelvic floor muscles externally and internally to gauge their tightness (tightness indicates PFD). Other IC and PFD experts, like ICA Medical Advisory Board member, Robert Moldwin, MD, perform a lidocaine challenge. By instilling lidocaine into the bladder, Dr. Moldwin determines whether your pain is coming from your bladder, which would indicate IC.
Although many centers are familiar with retraining techniques to improve pelvic floor dysfunction, few have the multidisciplinary expertise to teach patients with constipation how to appropriately coordinate abdominal and pelvic floor muscles during defecation, and how to use bowel management techniques, along with behavior modification, to relieve symptoms. Because pelvic floor dysfunction can be associated with psychological, sexual or physical abuse and other life stressors, psychological counseling is often included in the evaluation process.
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.
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.
Nicole Davis is a writer based in Madison, WI, a personal trainer, and a group fitness instructor whose goal is to help women live stronger, healthier, happier lives. When she’s not working out with her husband or chasing around her young daughter, she’s watching crime TV shows or making sourdough bread from scratch. Find her on Instagram for fitness tidbits, #momlife and more.