Pelvic Floor Spasm: The missing link in chronic pelvic pain
Acute or chronic pelvic pain is often due to musculoskeletal disorders, which may go unrecognized during a traditional pelvic examination. Proper evaluation facilitates the diagnosis of spasm or trigger points, and physical therapy often achieves a major improvement in quality of life for these women.
Pelvic floor musculoskeletal disorders are common in women and too often go unrecognized during the evaluation of pelvic pain syndromes. Although well described in the literature, these disorders cause diverse symptoms that may be missed by a traditional examination of the cervix, uterus, and adnexa. Screening the inferolateral pelvic floor musculature during a routine pelvic examination is very useful for identifying spasm and trigger points contributing to, or resulting from, a patient’s pelvic pain. A brief palpation of the posterior and lateral pelvis to identify spasm in the levator ani (pubococcygeus, iliococcygeus, and puborectalis) often identifies components of pelvic pain that may be dramatically improved by physical therapy and other interventions. We present a case series and review describing the successful identification and management of these acute and chronic syndromes.
PREVALENCE AND CAUSES OF PELVIC PAIN
Pelvic pain is relatively common among women, with a prevalence of at least 3.8%. 1,2 Symptoms of pelvic pain may require frequent use of medical resources and a significant number of surgical interventions. It is estimated that 40% of diagnostic laparoscopies and 12% of hysterectomies are performed for pelvic pain. 3 Unfortunately, some of these patients have a diagnosis that is not surgically correctible or have a multifactorial etiology for their pain, which therefore persists despite surgery.
The pelvic floor musculature is well recognized as a potential cause of acute and chronic pelvic pain, but it is too often neglected during the evaluation of pelvic pain. Musculoskeletal etiologies for acute and chronic pain should be included in the initial assessment of such patients. 1 Unfortunately, criteria for diagnosing musculoskeletal pain of the pelvis have not been established or validated. 4
The pelvic floor consists of striated muscles, ligaments, and connective tissues that support the pelvic organs against gravity and intraabdominal pressure. The pelvic diaphragm is composed of the coccygeus muscle posteriorly and the levator ani anterolaterally. Although they are not fully distinct, the components of the levator ani consist of the iliococcygeus, the pubococcygeus, and the puborectalis muscle group. The pelvic floor must allow relaxation of this support at the urogenital hiatus during voiding and parturition while maintaining the anatomic position of pelvic structures. The complex mechanics of its bimodal function and frequent insults to the integrity of the pelvic diaphragm from gravity, daily activities, and vaginal birth contribute to the pelvic musculature’s vulnerability to damage and injury. Lying within the pelvic cavity are the piriformis, and obturator muscles, which are not elements of the pelvic diaphragm but may contribute to pelvic pain when injured.5
Pelvic floor hypertonus may be the primary cause of pelvic pain in some patients; in others it may simply be a response to the underlying pelvic disorder.6 Several mechanisms of injury may lead to spasm of the pelvic floor. These include, but are not limited to, traumatic vaginal delivery, pelvic surgery, positional insults such as prolonged driving or occupations that require prolonged sitting, gait disturbances, traumatic injury to the back or pelvis, and sexual abuse. Malalignment of the pelvis, especially in the sacroiliac joint, due to trauma, poor posture, pelvic floor deconditioning, muscular asymmetry, or excessive athletics also may contribute to muscular dysfunction of the pelvis.
Injury leading to myofascial pain begins with an acute phase, characterized by inflammatory and immune responses. The injury may perpetuate itself with spasm promoting further inflammation, neurotransmitter release, and central nervous system sensitization. As the injury evolves, the second stage is the musculodystrophic stage, during which fibrosis develops and the process favors a chronic syndrome.
Pelvic floor dysfunction can also arise in response to other common chronic pain syndromes, such as endometriosis, irritable bowel disease, vulvodynia, and interstitial cystitis. A prospective evaluation of patients with chronic pelvic pain of various etiologies found abnormal musculoskeletal findings in 37%, versus 5% of controls.7 For this reason, the pelvic floor should be included in any evaluation regardless of the suspected source of pelvic pain.
As the 3 cases described on page 46 demonstrate, clinicians must maintain a high index of suspicion for musculoskeletal sources of pelvic pain to determine the appropriate diagnosis. Pelvic floor myalgia and other disorders of the pelvic floor musculature, such as piriformis syndrome, are often identified by a medical history and single-digit examination of the pelvic floor. Simply inverting the examining digits to assess the posterior and lateral pelvic musculature often provides a prompt clinical diagnosis. The 3 cases in the sidebar on page 46 illustrate the diversity of presentations and the ease of diagnosis when proper attention is paid to the pelvic floor musculature.