FIGURE 1 Transvaginal myofascial therapy
Physical therapy of the pelvic floor is more invasive than other forms of rehabilitative therapy because of the need to perform transvaginal maneuvers.
Need for specialized training may limit number of therapists
The randomized controlled study design renders these findings fairly reliable. Therapists were unmasked and aware of the treatment arms but were trained to make the different therapy sessions appear as similar as possible.
Although investigators were enthusiastic about their initial findings, additional studies are needed to validate the results. Moreover, these findings may be difficult to generalize because women who volunteer to participate in such a study may differ from the general population.
Nevertheless, patients who suffer from chronic pelvic pain may take heart that there is a nonpharmaceutical alternative to manage their symptoms, although availability is likely limited in many areas. Given the nature of the physical therapy required for this particular location of myofascial pain, specialized training is necessary for therapists. Despite motivated patients and well-informed providers, it may be difficult to find specialized therapists within local vicinities. Referrals to centers where this type of therapy is offered may be necessary.
WHAT THIS EVIDENCE MEANS FOR PRACTICE
Pelvic myofascial therapy is an effective and acceptable intervention for the treatment of levator myalgia.
The ideal agent for trigger-point injections remains a mystery
Langford CF, Udvari Nagy S, Ghoniem G M. Levator ani trigger point injections: An underutilized treatment for chronic pelvic pain. Neurourol Urodyn. 2007;26(1):59–62.
Abbott JA, Jarvis SK, Lyons SD, Thomson A, Vancaille TG. Botulinum toxin type A for chronic pain and pelvic floor spasm in women: a randomized controlled trial. Obstet Gynecol. 2006;108(4):915–923.
Trigger points are discrete, tender areas within a ridge of contracted muscle. These points may cause focal pain or referred pain upon irritation of the muscle.2 Trigger-point injection therapy aims to anesthetize or relax these points by infiltrating the muscle with medications.
These two studies evaluated the value of trigger-point injections in the treatment of pelvic myofascial pain; they found that the injections provide relief, although the mechanism of action and the ideal agent remain to be determined.
Langford et al: Details of the study
In this prospective study, 18 women who had pelvic pain of at least 6 months’ duration and confirmed trigger points on examination underwent transvaginal injection of a solution of bupivacaine, lidocaine, and triamcinolone. They were assessed by questionnaire at baseline and 3 months after injection. Assessment included a visual analog scale for pain severity. Investigators defined success as a decrease in pain of 50% or more and global-satisfaction and global-cure visual scores of 60% or higher.
Thirteen of the 18 women (72.2%) improved after their first injection, with six women reporting a complete absence of pain. Overall, women reported significant decreases in pain and increases in the rates of satisfaction and cure, meeting the definition of success at 3 months after the injection.
Among the theories proposed to explain the mechanism of action of trigger-point injections are:
- disruption of reflex arcs within skeletal muscle
- release of endorphins
- mechanical changes in abnormally contracted muscle fibers.
This last theory highlights one of the limitations of this study—lack of a placebo arm. Could it be possible that the injection of any fluid produces the same effect?
This study was not designed to investigate the causal relationship between the injection of a particular solution and pain relief, but it does highlight the need for studies to clarify the mechanism of action, including use of a placebo. It also prompts questions about the duration of effect after a single injection.
Goal of chemodenervation is blocking of muscle activity
Botulinum toxin type A (Botox) blocks the release of acetylcholine from presynaptic neurons. The release of acetylcholine stimulates muscle contractions; therefore, blockage of its release reduces muscle activity. This type of chemodenervation has found widespread use, and botulinum toxin A now has approval from the Food and Drug Administration (FDA) for treatment of chronic migraine, limb spasticity, cervical dystonia, strabismus, hyperhidrosis, and facial cosmesis.3 Although it is not approved for pelvic floor levator spasm, its success in treating other myotonic disorders suggests that its application may be relevant.
Abbott et al: Details of the study
Abbott and colleagues performed a double-blind, randomized, controlled trial to compare injection of botulinum toxin A with injection of saline. They measured changes in the pain scale, quality of life, and vaginal pressure.
Women were eligible for the study if they had subjectively reported pelvic pain of more than 2 years’ duration and objective evidence of trigger points (on examination) and elevated vaginal resting pressure (by vaginal manometry). Neither the clinical research staff nor the patient knew the contents of the injections, but all women received a total of four—two at sites in the puborectalis muscle and two in the pubococcygeus muscle.