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.
Anatomy and Function
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.
The nerve supply to the pelvic floor structures is primarily from sacral nerves S3 and S4 as the pudendal nerve. The predominant blood supply is derived from parietal branches of the internal iliac artery.
The muscles of the pelvic floor have three functions:
A wide variety of conditions are attributed to PFD due to hypertonicity, hypotonicity, loss of pelvic support, or mixed concerns.
The causes of pelvic floor dysfunction are not well understood. No specific inciting event or factor has been generally identified as an etiology of PFD, but multiple factors have been discussed. Hypertonicity symptoms associated with voiding and defecation difficulties might be related to learning poor evacuation techniques. Habitual efforts to avoid urination or bowel movements might be lifestyle attributing factors. Dyssynergic defecation may begin in childhood. Surgical or obstetric trauma may lead to muscular pain with hypertonicity of the pelvic floor.
Sexual abuse has been associated with chronic pelvic pain. Posture, gait and skeletal asymmetry may contribute to pelvic muscular pain. Degenerative neuromuscular disease, spinal nerve injury, lower back injury, or surgery may contribute to pelvic floor dysfunction. Dyspareunia from atrophic vaginitis or vulvodynia may contribute to reinforced muscle contraction resulting in pelvic pain. Irritable bowel syndrome, endometriosis, interstitial cystitis are some visceral syndromes that might contribute to PFD pain. Again, symptoms of PFD are often interrelated between urologic, gynecologic, and colorectal concerns. “Cross-talk’ via normal regulation to the bowel, bladder, and sexual function may explain the interaction of pelvic pain syndromes. Muscle relaxants, narcotics, alpha-blocking agents, calcium-channel blockers, and methyldopa can increase smooth and skeletal muscle relaxation, possibly contributing to incontinence. Antihistamines and anticholinergics may have additive effects leading to urinary hesitancy and retention. Additional factors contributing to PFD include advancing age, obesity, childbearing, and hysterectomy.
As the symptoms and conditions of pelvic floor dysfunction span a broad spectrum of disciplines, determining the overall incidence of the amalgam of disorders is difficult. By the age of 80, about 11% of women will have one or more surgical interventions for urinary incontinence or pelvic organ prolapse. Sexual dysfunction has been identified as a common problem involving up to 40% of reproductive-age women. PFD can affect up to 50% of childbearing women. Population-based survey studies have identified a lifetime prevalence of 17% to 19% for sexual pain disorders Women with PFD concerns are more likely to report decreased arousal, infrequent orgasm, and increased dyspareunia. For women of childbearing age, PFD and POP are very common, and 65.8% of women over 40 years report at least one complaint of sexual dysfunction. Interestingly, studies have not found sexual dysfunction to be directly related to PFD complaints of POP, stress urinary incontinence, overactive bladder, obstructed defecation, and fecal incontinence.
The lifetime risk is 20.5% for women having a surgical intervention related to stress urinary incontinence. Though much attention is directed toward women with concerns and findings referable to PFD, 16% of men have been identified with PFD. POP is a growing concern as the world’s population ages.
In the United States, 10% to 20% of individuals are affected by defecation disorders accounting for 1.2 million annual physician visits. The incidence of defecatory disorders in Olmsted County, Minnesota, is 16 per 100,000 person-years. Of patients being evaluated for constipation, 40% have dyssynergic defecation.
Patients can have a complex of multiple symptoms, as noted in a study with 82% of patients with defecatory disorders having multiple urinary symptoms.
The causes and functional processes of conditions related to PFD are not fully understood. The mechanical aspects of pelvic organ prolapse are related to the widening of the levator hiatus and laxity of the pelvic floor with decent relative to the pubococcygeal line. These changes might be related to obesity, menopause, pregnancy, and childbearing. Along with obesity, POP is associated with increased intrabdominal pressure with straining to defecate. The concerns correlating childbirth to PFD apply to women following both Cesarean or vaginal deliveries. The laxity of the pelvic floor might be related to collagen abnormalities that are either inherited or acquired related to pregnancy.
Defecation is the complex coordination of increased intraabdominal pressure with the relaxation of the pelvic floor and anal sphincter complex, requiring intact anorectal sensation and proprioception. Rectal distention initiates the stimulation for relaxation of the puborectalis and anal sphincter to allow evacuation. Relaxation of the puborectalis and pelvic floor allows the angle (normally about 90 degrees) between the anus and rectum to straighten, facilitating defecation. Patients are not able to evacuate with satisfaction when relaxation does not occur.
Evaluation of patients with PFD and POP concerns are initially directed toward their presenting complaints. As noted previously, the complaints and concerns often involve multiple systems requiring multidisciplinary care. Multiple forms of evaluation are available, but none are specifically diagnostic for PFD. Various tests are incorporated to augment the physician's clinical perception.
Therapeutic interventions for patients with pelvic floor dysfunction should be tailored to their specific needs. A multidisciplinary approach is often necessary. Patients with a history of sexual, physical, or emotional abuse should have the information relayed to the entire treatment team to facilitate modifications of therapy to accommodate the patient’s needs.
Surgical procedures are indicated for anatomic prolapse concerns that do not have satisfactory symptom relief with non-operative measures.
Pelvic pain is a frequent symptom related to PFD. Other common etiologies for pelvic pain should be considered including prostatitis, prostatodynia, urinary tract infection, urolithiasis, urethral diverticula, bladder neoplasm, myofascial pelvic pain, interstitial cystitis, endometriosis, adnexal tumors, uterine leiomyomas, ovarian retention syndrome, pelvic congestion syndrome, vulvodynia, gynecologic neoplasm, chronic intermittent bowel obstruction, chronic constipation, irritable bowel syndrome, diverticular disease, inflammatory bowel disease, rectal neoplasm, pelvic abscess, pelvic hernias, spinal/sacral neoplasia, neuropathy or entrapment in the pelvis, abdominal epilepsy, and abdominal migraines. Urinary incontinence might be related to overflow incontinence due to excessive urinary volume. Similarly, fecal incontinence can be secondary to encopresis with retained stool. Hemorrhoid prolapse is often mistaken for rectal prolapse.
There are no universally curative therapies for PFD. Patients with both hypertonicity and hypotonicity symptoms can obtain some benefit from lifestyle changes, medications, and manipulative interventions, but seldom have complete resolution of symptoms. Typical for intervention for PFD, physical therapy techniques have demonstrated a 59% to 80% improvement or relief of women’s symptoms with pelvic floor hypertonicity. As an example, an abdominal rectopexy for rectal prolapse has a 3% to 9% recurrence rate. Unfortunately, the incidence of failure or recurrence increases with time. Women with POP have improvements in sexual function and dyspareunia with surgical repair of the prolapse. Surgical interventions can correct the anatomic concerns of POP.
For the varied conditions of pelvic floor dysfunction, the greatest complication is treatment failure with the persistence of symptoms such as incontinence. Lifestyle modifications and physical therapy, including biofeedback, have no major defined complication risks. Neglected pessaries have the risks of erosions, incarceration, or fistula. Sacral nerve stimulation is a safe procedure with minor complications of 12% lead dislocation and 3% infection.
Surgical revision is not uncommon for the device or lead failure or battery depletion. Postoperative morbidity for POP surgery includes the usual surgical concerns such as infection, bleeding, and medical risks along with visceral injury to adjacent structures. Indicative of these risks is the morbidity of 26% with anterior resection for rectal prolapse.
Primary care physicians (including gynecologists)are usually the first level of evaluation. They are in a position to obtain a thorough history and focused physical exam on initiating the patient’s treatment to include physical therapy. With complex and interrelated complaints, referrals to appropriate specialists are indicated. Physicians with added training for PFD include urologists, urogynecologists, and colon and rectal surgeons.
The involvement of a sex therapist is essential, particularly for dyspareunia with long-standing personal or relational distress or unresponsive to physical therapy. POP is associated with an aging population and can require the assistance of a geriatric specialist. In the management of PFD, the services of a physical therapist specially trained in pelvic floor disorders are invaluable.
Patients (men and women) are reluctant or unable to adequately discuss urinary concerns, sexual dysfunction, and bowel function difficulties. In an attempt to standardize and facilitate obtaining the patient’s sensitive information, the Pelvic Floor Disorders Consortium (PFDC) reviewed multiple symptoms, function, and quality of life questionnaires. The PFDC is composed of colorectal surgeons, urogynecologists, urologists, gynecologists, gastroenterologists, physiotherapists, and other advanced care practitioners indicative of the broad and complex concerns of PFD. The final IMPACT (Initial Measurement of Patient-Reported Pelvic Floor Complaints Tool) Long Form consists of 85 questions for men and 85 to 94 questions for women. An IMPACT Short Form reduces the questions to 34 for men and 45 for women.
Education of pelvic floor anatomy and function is important for the patient. Both pelvic floor exercises and relaxation techniques should be instructed.
Spinal cord injury patients represent a group with non-relaxing anal sphincters but from an anatomically defined etiology. These patients accomplish acceptable bowel control with training- use the Gastrocolic Reflex with increased bowel motility shortly after a meal along with rectal stimulation with either a suppository or enema for reflexive sphincter relaxation to facilitate evacuation. The author uses this training principle along with an oil-based laxative (mineral oil or Kondremul) frequently to manage patients with dyssynergic defecation.
Pelvic floor dysfunction is a prime example for healthcare professionals to provide patient-centered care. The symptoms, concerns, and findings related to pelvic floor dysfunction involve urologic, gynecologic, and colorectal issues and are often multiple and interrelated. The primary care physician is usually the initial provider the patient entrusts with these complaints. The incidence of traumatic, sexual, or personal abuse is high in this patient population. Communication and sensitivity are imperative for all healthcare workers that the patient encounters to assure confident and empathetic care is provided. The primary care physician will rely on an interprofessional team of specialists, including urologists, gynecologists, urogynecologists, and colon and rectal surgeons, to assist with the evaluation and management of these complex patients. The interprofessional team also includes the radiologists and their support technicians to perform pelvic floor imaging studies. In the care of these patients, pain management might be called upon to control symptoms. Specially trained physical therapists are key members of the interprofessional team.
Patient communication of their symptoms and concerns is very difficult. The Pelvic Floor Disorders Consortium has developed the IMPACT long and short forms for the collection of information and to provide standardization for further studies. [Level I] With these tools, patients can be evaluated and monitored in a more consistent manner.
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