A hypertonic pelvic floor occurs when the muscles in the pelvic floor become too tense and are unable to relax. Many people with a tense and non-relaxing pelvic floor experience pelvic health concerns such as constipation, painful sex, urgency and pelvic pain. A hypertonic pelvic floor may also be accompanied by tension in surrounding hip and pelvic muscles such as the piriformis, obturator internus, coccygeus and hamstrings.
Chronic pelvic pain affects 15% of women, resulting in considerable psychological, physical and economic burden and is difficult to treat. Tenderness or hypertonicity of the pelvic floor muscles can be a hyperalgesic muscular response in women with chronic pelvic pain. Pelvic floor hypertonicity is not routinely evaluated by physicians3 and is therefore likely underdiagnosed. This form of myofascial pain can represent a primary problem or a secondary adaptation to an acute or chronic injury to one or more of the musculoskeletal components within the pelvic floor and surrounding structures. Chronic pelvic diseases such as endometriosis or interstitial cystitis can cause persistent hypertonic pelvic floor during or long after treatment for the disease and are often associated with sensitization of the central nervous system. Because of the deep location of these muscles and the proximity of many visceral, neural and vascular structures, patients often cannot identify the source of their problem as musculoskeletal and present with a myriad of other symptoms, ranging from dyspareunia to slow urinary stream, constipation and vaginal pressure.
There is no one defining cause of a hypertonic pelvic floor; however, there are several activities that can lead to the muscles tightening up. As an example, many people who spend a lot of time working out and holding onto their core muscles can develop tension in their pelvic floor because they keep these muscles switched ‘on’ without giving the muscles time to relax and let go.
People who have a history of holding on to their bladder and/or bowels can also develop tension in their pelvic floor muscles. For instance, some people feel uncomfortable using public toilets so may hold on to their bladders for hours until they come back home from school, work or social activities. The act of holding on means the pelvic floor muscles are tightening to prevent the loss of control.
As high levels of stress, fear or anxiety can cause muscles to reflexively tighten, these factors can lead to a hypertonic pelvic floor.
Pelvic health and abdominal health conditions can also result in hypertonicity of the pelvic floor.
The most commonly implicated mechanism for these symptoms is dysfunctional voiding or defecation, which either was never learned correctly or was acquired in adulthood through the voluntary holding of urine or stool. This voluntary holding might be attributable to habit, lifestyle, occupation, or constant recruitment of muscles used to avoid bowel or bladder incontinence. Conditions that result in dyspareunia (eg, atrophic vaginitis, vulvodynia) may trigger involuntary muscle contraction of the pelvic floor. This pattern is reinforced over time, particularly if intercourse is continued despite the pain, and can potentially lead to persistent contraction of the pelvic floor and symptoms of non-relaxing pelvic floor dysfunction.
Injury to the pelvic floor from surgery or trauma can result in painful, hypertonic muscles. Pelvic surgical procedures such as mesh placement or permanent sutures in the muscles, as well as obstetric injury, have been reported to result in muscular pain and hypertonicity of the pelvic floor.
Visceral pain syndromes associated with chronic pelvic pain include irritable bowel syndrome, endometriosis, and interstitial cystitis or painful bladder syndrome. These may be associated with non-relaxing pelvic floor muscles through central and peripheral sensitization and lowering of nociceptive thresholds, resulting in neuropathic up-regulation, hypersensitivity, and allodynia. Pain may be referred from visceral organs to muscles and vice versa.
Postural or gait abnormalities, skeletal asymmetry, and prolonged sitting may trigger symptoms in some individuals. Because the lower extremity, hip, abdomen, pelvis, and spine are a connected kinetic chain, any dysfunction along this chain may cause overcompensation and dysfunction of other associated muscles.
Often, the specific cause or inciting event that leads to non-relaxing pelvic floor dysfunction is never identified. A series of events or a combination of factors may contribute to the development of the problem. Perpetuating factors include those that commonly complicate chronic pain such as sleep disturbance, depression, and anxiety.
The pelvic floor is a dome-shaped muscle complex with contraction occurring in 3 planes. Its complex actions include tightening, lifting, squeezing, and relaxing. Pelvic floor muscles support organs within the pelvis and lower abdomen, maintain continence, allow for bladder and bowel emptying, and contribute to sexual arousal and orgasmic function. Although there is no single standard for assessing the function of the pelvic floor, a focused approach to the physical examination, including an assessment of the patient’s ability to contract and relax the pelvic floor muscles, is useful.
Assessment begins with a visual inspection of the vulva, perineum, and anus. The patient is asked to perform a pelvic floor contraction (ie, to contract the muscles that are used for stopping urinating). When effective, contraction results in an upward lift of the perineum. Some women may inappropriately strain instead of contracting the pelvic floor muscles, resulting in the descent of the perineum.
Digital palpation of pelvic floor muscles
Digital palpation of the pelvic floor muscles is used to assess contraction and relaxation and to evaluate pain. External palpation of the urogenital triangle includes the ischiocavernosus, bulbospongiosus, transverse perineal muscles and the perineal body. Assessment of muscle tension and tenderness of the urogenital triangle is especially important in women with dyspareunia. The deeper muscles include the pubococcygeus, puborectalis, and iliococcygeus, known together as the levator ani, and the obturator internus on the lateral pelvic wall. Pelvic floor muscles are assessed for tenderness, tone, contraction, and relaxation through vaginal and rectal digital palpation. Pelvic floor muscles are assessed for tenderness, tone, contraction, and relaxation through vaginal and rectal digital palpation. The strength of a pelvic floor contraction can be classified subjectively as absent, weak, normal, or strong after asking the woman to squeeze around the palpating finger. A rectal examination is important, not only to assess the anal sphincter but also to evaluate the coccygeus, levator ani muscles, sacrococcygeal ligaments, and attachments to the sacrum and coccyx.
Diagnostic evaluation might include anorectal manometry with balloon expulsion, anal endosonography, defecography, urodynamic testing, cystoscopy, electromyography, ultrasonography, and static or dynamic magnetic resonance imaging. Anorectal manometry and rectal balloon expulsion studies can help confirm the diagnosis of defecatory disorders by documenting inadequate intra-abdominal pressure during straining, incomplete evacuation of the rectum, and inadequate relaxation of anal canal pressures. These tests are usually undertaken by the specialist colorectal, gynaecological, neurological, or urological teams rather than the Pain specialists.
This would include:
Other methods to treat refractory non-relaxing pelvic floor dysfunction may include trigger point injections using a local anaesthetic and corticosteroid; botox trigger point injections; acupuncture; and neuromodulation with sacral, pudendal, and posterior tibial nerve stimulation. Pudendal nerve blocks can also help in relaxing the pelvic floor muscles. These treatments are associated with varying degrees of success.
Providing education about the anatomy and function of the pelvic floor is important and should be a routine part of women’s health care, particularly around the times of childbirth and menopause, when changes in the pelvic floor are common. Women are frequently unfamiliar with pelvic floor muscles and their function. Pelvic floor strengthening exercises (Kegel exercises) originally were developed to treat urinary incontinence and are commonly taught today, but it is important to remember that the pelvic floor has many other functions beyond maintaining urinary continence. Thus, instruction on relaxation and the integrated function of the pelvic floor muscles is equally important.
Pelvic floor rehabilitation with neuromuscular education is the cornerstone of therapy for women with nonrelaxing pelvic floor dysfunction. Therapy is ideally provided by a physical therapist with training in pelvic floor dysfunction. The specific therapy used is guided by symptoms and usually includes strategies to optimize lumbopelvic and spinal function and to improve bowel, bladder, and sexual function. Manual techniques may include trigger point massage, myofascial release, strain-counter strain, and joint mobilization, among others. In addition, exercises to strengthen and stabilize the core muscles usually are included with pelvic floor physical therapy.
Biofeedback is a neuromuscular training approach in which patients learn how to appropriately contract or relax muscles; efforts are aided by visual or auditory feedback of muscle activity. Controlled clinical trials demonstrate that biofeedback therapy to improve anal and pelvic floor relaxation improves symptoms in defecatory disorders.
Women with deep dyspareunia associated with nonrelaxing pelvic floor dysfunction generally should be counselled to avoid penetrative sexual activity until pelvic floor muscles are rehabilitated. Referral to a sex therapist is also important, particularly if the dyspareunia is long-standing, associated with personal or relational distress, or unresponsive to initial physical therapy of the pelvic floor. If a woman has experienced physical, sexual, or emotional abuse, her treatment plan needs to take into consideration the nature of the abuse and the status of her recovery.
Neuropathic pain modulators, including amitriptyline, nortriptyline, gabapentin, and pregabalin, are frequently used for managing other conditions of chronic pain, but tricyclic antidepressants may aggravate bowel and bladder symptoms and should not be the first-line therapy for non-relaxing pelvic floor dysfunction.
Injecting botulinum toxin type A (Botox) into hypertonic pelvic floor muscles may aid the relaxation of pelvic floor musculature. The muscles that are injected in chronic pelvic pain treatment include the obturator internus, levator ani (pubococcygeus, iliococcygeus, and puborectalis), and coccygeus. Other muscles including the transverse perineal, obturator internus and piriformis muscle may be injected. Generally, injections can be performed tolerably under local anaesthesia alone. Side effects of Botox injection in chronic pelvic pain are rare and self-limiting. Because of the reversible nature of Botox, reinjection appears to be necessary. Increasing proof points out that Botox is a promising treatment option for chronic pelvic pain in women.
Nesbitt-Hawes et al reported that clinical outcomes for single and subsequent Botox injections for recurrent pelvic pain are similar. In the subsequent injection, there is a cumulative effect with lower vaginal and maximal contraction pressures. Long-term treatment with Botox is generally tolerable and efficient; nevertheless, following an initial positive therapeutic effect, symptoms may fail to respond to upcoming treatments. Attributing factors considered for secondary nonresponse may include the development of neutralizing antibodies, missed injection of the target muscles, disease progression, and architectural changes following repeated injection. There is limited knowledge on the long-term implications, so further studies are required. Women who have benefitted from a single Botox injection can be informed that, if symptoms reoccur, repeated injections can be expected to be equally efficacious.
Side effects are rare and include pain at the injection site, hematoma, and infection. The prevalence of side effects is similar to traditional trigger point injection therapy when used for myofascial pain. Adverse events associated with the neuromuscular effects of Botox have been rare and are dose-dependent. Faecal incontinence has occurred in less than 5% of patients after perianal injections of BTX/A and is also dose-related.
Botox injections at Pain Spa
At Pain Spa, Dr Krishna is very experienced in performing injection treatment for patients with various pelvic floor disorders. He has excellent knowledge of the pelvic floor anatomy, which is paramount for accurate identification and subsequent injection of botox into these muscles.