Respondents to an international survey sponsored by the Academy of Pelvic Health Physical Therapy indicated that manual therapy (MT) techniques are commonly used to manage symptoms associated with persistent pelvic pain disorders.1 Different guidelines and authors use different terms to describe pelvic pain and its associated qualities2–4; for purposes of the initial survey and this article, the European Association of Urology (EAU) definition of pelvic pain is used. The EAU defines persistent pelvic pain as pain perceived in structures of the pelvis of men or women, often associated with negative psychological, behavioral, sexual, and emotional consequences. This pain may also present with urinary tract, sexual, bowel, pelvic floor, and/or gynecological dysfunction.3
Respondents to the survey used soft-tissue biased MT techniques on external (94%) and internal (76%) pelvic structures, and the viscera (44%), and joint-biased MT techniques (82%).1 Manual therapy is a systematic application of care that involves extensive critical reasoning to deliver an intervention using “skilled hand movements and skilled passive movements of joints and soft tissue.”5 A staggering variety of MT practices and philosophies exist and are used by many different professions to relieve pain. Comparisons of these philosophies of MT show small effects on pain-related outcomes; that is, all types of MT seem to be more effective than doing nothing, but no one philosophy is superior over another.6 How then do we maximize the change in MT outcomes for each person with pelvic pain who sees a physiotherapist (PT)?
Pain relief after any intervention can be attributed to 3 factors that are the focus of this article. First, we discuss effects that are unrelated to the intervention or how it is performed. Next, there are the effects specific to the chosen intervention when it is provided without context. Finally, we consider the effects of the context surrounding every intervention.
Many conditions have variations or fluctuations of symptoms over time in the absence of any intervention, and the course of many diseases is improvement.7 For someone in pain, changes in pain intensity may represent spontaneous remission of the symptoms regardless of intervention.8 The influence of natural history is stronger the sooner we see someone after the onset of pain. Analysis of studies of interventions for acute low back pain (LBP), for example, indicated that only a small amount of the variation in outcomes (3%) is explained by “treatment factors” (eg, type of intervention or type of provider), with the majority explained by natural history and “other” effects9 (discussed later).
Regression to the Mean
This is a statistical phenomenon that occurs in any repeated measurement. Very high responses on a measure are often followed by a lower response at a second measurement (or a higher response if the first one is low).10 Most people seek care when their pain intensity is high and is interfering with their life. The pain intensity is statistically likely to be lower when they return at a subsequent visit. A clinical example of this phenomenon is demonstrated in a study that compared individuals with temporomandibular joint dysfunction (TMD) seeking care with those with TMD not seeking care.11 The greatest change in pain happened for people with the highest pain at baseline, regardless of whether that person sought treatment. Thus, changes in both groups of people were directly related to regression to the mean and not due to any intervention they might have undergone.
Some commentators have suggested positive changes in outcomes unrelated to treatment ought to dissuade both patients and providers from using MT for acute pain conditions. However, a developing body of literature indicates that early intervention by PTs for pain, while not necessarily outperforming other interventions in terms of outcomes, saves health care systems thousands of dollars per patient and is protective from downstream exposure to imaging and pharmacotherapies.12,13
Individuals with pelvic pain receive opioid therapy against guideline recommendations.14,15 Cichowski et al16 examined prescribing patterns of opioids for women with chronic pelvic pain and reported immediately increased opioid use that continued for up to 5 years following a formal diagnosis of pelvic pain without meaningful changes in pain intensity. Sixty percent of participants with vulvodynia reported using opioids and other adjuvant pain medications to manage their symptoms, whereas 57% reported using a combination of opioids, adjuvant drugs, and alcohol.17 Despite this use, women reported that their pain control continued to be inadequate.
These data are concerning but support efforts to promote early access to PT including MT. Physiotherapists endorse MT as a treatment of choice for patients presenting with pelvic pain, and early involvement of PTs in pain management can reduce opioid use for pain18–20 and therefore opioid exposure. Reducing opioid exposure has the potential to limit transition from opioid use to abuse for patients in pain. Unfortunately, early access to PT for women with pelvic pain is not common, as is access to medical providers who specialize in pelvic pain. Alappattu et al21 reported that women with pelvic pain suffered symptoms for more than 5 years before presenting to a physician who specialized in management of pelvic pain. This delay may be associated with a number of factors. First, pelvic pain and its associated medical diagnoses are often diagnoses of exclusion (ie, vulvodynia, myofascial pain) that may be associated with musculoskeletal involvement; however, to rule out medical causes of this pain, early treatment of pelvic pain often consists of imaging, pain, and/or hormonal medications and, in some cases, surgery. In a qualitative study by McGowan and colleagues,22 general practitioners reported that due to the complexity of pelvic pain and difficulty identifying a medical diagnosis, they relied on comprehensive medical workups to exclude serious pathology. The general practitioners and nurses interviewed in this study reported that the most common providers to whom they referred women with pelvic pain were gynecology, gastroenterology, pain medicine, and psychological services; physical therapy was not mentioned. Many providers may be unaware that PTs with advanced postprofessional training are skilled to manage musculoskeletal pelvic pain. Consequently, despite the fact that regression to the mean and natural history influence outcomes for treatment of acute pain, early PT involvement has potential additional health benefits beyond changes in pain.
Effects related to any intervention for pain have been differentiated as specific and nonspecific.23,24 The specific effect of a medication, for example, results from the interaction between the active ingredient in the drug and the intended molecular target, whereas nonspecific effects are related to the patient's beliefs that the drug will help. While we agree with this designation in principle, labeling mechanisms of pain relief as specific and nonspecific minimizes the complexity of “nonspecific effects,” making some providers less willing to endorse an intervention that has substantial “nonspecific” mechanisms. We refer to these effects as those independent of the context and effects dependent upon the context, as we believe these terms are more accurate than “specific” and “nonspecific” effects.
Effects Independent of Context
Manual therapy has traditionally been taught with a biomechanical emphasis.25 Physiotherapists endorse the importance of biomechanics in directing the use of MT interventions.26 Evaluation of individuals presenting with pelvic pain is often driven by presumed mechanical joint and soft-tissue impairments.2 Providers spend years studying and practicing numerous MT approaches as well as assessment techniques to identify where, how, and in whom to apply these interventions. Importantly, patients value these skills in providers27 and overwhelmingly choose providers based on perceived experience and technical skills.28 Certainly, MT imparts measurable forces to the target tissues, moving tissues, and joints. Force transmission through the spine is detected during manipulation.29 Motion of spinal segments is seen using magnetic resonance imaging.30 Diagnostic ultrasound imaging shows movement in the neurovascular bundle31 and changes in muscle shape and quality.32 Fibrotic nerve and connective tissue is reduced in rats that receive a soft-tissue biased MT.33 Thus, MT causes motion and changes in tissue quality.
The challenge to this paradigm is the extent to which changes in tissue quality or mobility relate to changes in outcome. The assumption is that peripheral tissues are where the pain originates and is maintained; therefore, if we change the tissue, we must change the cause of the pain. However, such an approach is driven by a biomedical model. A refined understanding of pain suggests the importance of multidimensional approaches, particularly given the notoriously poor relationship that is observed between tissue damage and clinical presentation.34 Gifford wrote that “physiotherapists have rarely questioned this paradox and have persevered with highly skilled physical tissue analyses aimed at validating the tissues and peripheral nerve trunks and roots as definitive sources of ongoing pain in the great majority of patient presentations.”35
Subsequently, while MT interventions impart forces to tissues and joints, intervention directed completely by a biomedical model and outcomes attributed solely to such an approach ignores a more complex understanding of pelvic pain and recovery. The disconnect between a purely biomedical explanation and clinical outcomes is apparent when painful conditions such as patellofemoral pain36 or shoulder impingement37 resolve without changes in impairments targeted by interventions. Similarly, MT directed at the sacroiliac joints does not result in measurable changes in the position of these joints38 and is not superior to other treatment approaches, including exercise.39,40 Manual therapy outcomes occur independently of whether or not the technique was chosen on the basis of a thorough clinical examination versus prescriptively determined with no knowledge of the patient presentation.41 Collectively, the literature supports an influence of MT on the peripheral tissues; however, the clinical relevance of changes in tissue mobility or quality on pain, in isolation of context, is difficult to determine.
Effects Dependent on the Context
We studied hard and practiced for years to improve diagnosis and intervention skills, becoming confident in our ability to deliver an appropriate technique to the appropriate patient. But has there been an occasion when you looked at your schedule and thought, “I don't want to do this today.” How does this thought affect the outcomes for treatment? What about the person you are treating? Was there parking available where she wanted it? How long did she have to wait to get back to your room? How was traffic on the way to clinic? She read an Instagram post about pelvic pain and that painful sex shouldn't be ignored. How do these experiences shape our patients' encounters with us and our staff and influence pain-related outcomes of our interventions?
Responses to any intervention for pain are influenced by the expectations of the patient with pain, our own expectations and self-efficacy as providers, and the therapeutic context within which the intervention is applied.24,42,43 All of these aspects are strengthened by our training and practice and can be explicitly harnessed to improve MT effectiveness.
We expect many things from our health care. We have expectations about the environment where care occurs and processes related to its provision. But we also have expectations about the outcome of that care.
Among the many expectations held by a person in pain is the overall expectation for recovery. Such general expectations for recovery have been found to influence outcomes for a wide variety of interventions for pain.44–47 Waljee et al44 reviewed the impact of these patient expectations on a variety of domains after surgery and found that positive expectations for care were correlated with improved outcomes, especially for pain, disability, and mood. Our own analyses suggest that expecting to recover is associated with reported recovery in patients with lumbar45 and shoulder pain.46 Furthermore, improvements in disability in patients seeking care from various providers, including physicians, chiropractors, acupuncturists, and massage therapists, were related to the general expectation for improvement, independent of provider or intervention.47 These studies and others support the role of positive overall patient expectations for care as an important aspect of recovery from pain.
Expectations about a specific intervention have also been shown for many different interventions. Intervention-specific expectations are most influential when patients receive an intervention for which they have the greatest expectations (ie, intervention “matched” the expectations). Barrett et al48 showed this in patients with symptoms of the common cold. Illnesses were substantively shorter and less severe in participants who believed that medication would help and were randomized to receive a pill (Echinacea or placebo) compared with those who received advice.48 Similarly, in patients with pain, those who expected greater benefit from massage and received massage had better outcomes than when they received acupuncture49 and providing an intervention for which the patient has positive expectations predicts outcome after interventions for spinal pain.45,50
It is pertinent to note at this point that expectations for an intervention can be modified by the language used to describe the intervention. We have consistently observed a hypoalgesic response to spinal manipulation,51 with the exception occurring in a study in which we instructed participants that they might experience more pain.52 Subsequently, expectations may both positively and negatively influence outcomes and change during the episode of care,53 suggesting that the language we use with patients is very important.
Provider Expectations and Self-efficacy
Not only do our patients have expectations for our interaction but also we have expectations as providers. We have expectations about how the patient should respond to our care. We also have expectations about which interventions will work for which patient developed through our training and experiences. Such preconceived opinions of effectiveness influenced the pain and disability outcomes in a pragmatic trial comparing thrust with nonthrust joint-biased interventions for back pain.54 In our own work, having a preference for an intervention, any intervention, influenced subsequent pain relief, independent of which intervention was applied.55 Physicians' high expectations for a good outcome at the initial evaluation of patients in musculoskeletal pain predict better outcomes for patients, independent of the intervention delivered.23 Providers' beliefs in an intervention to help a patient are strongly associated with providers' clinical and interpersonal behavior.56 Patients choose providers based on perceived experience and technical skills.28 We interpret these combined findings as an indication that provider self-efficacy and confidence are important for outcomes.
The therapeutic context in which an intervention is delivered includes the social and physical environment where the episode of care occurs.57 Associated with this is “therapeutic alliance,” a caring bond between the patient and the provider.58 Measures of alliance are associated with improved outcomes in rehabilitation.59 The words and tone of the provider, the environment, and the perceived expertise of the provider influence therapeutic alliance and the expectations of the patient all impact recovery. The concept of “therapeutic ritual” is also intertwined with the idea of therapeutic context.
These concepts are overlapping and interdependent. Great examples of this come from “hidden administration” studies of drug efficacy in the pharmacological literature.60 In these studies, efficacy of medications is tested through “open injection” versus “hidden” injection. As the name suggests, open injection occurs when the patient or participant can watch the provider inject the medication into an intravenous line. Hidden injections are the opposite—the medication is delivered by a timer or behind a screen so that the person is unaware of when the injection occurs. These studies have established that the relief from medications as varied as buprenorphine, tramadol, and ketorolac is dramatically reduced or, in fact, eliminated as in the case of metamizol.61 In these studies, the drug efficacy is related to therapeutic context (an injection, given by a health provider, in a health care setting) and expectation (I am getting a drug for pain). The same is true for our interactions during the provision of MT.
PUTTING IT TOGETHER
How then can we use this information to improve MT outcomes for our patients with pelvic pain? First, we are not indicating that musculoskeletal examination of the patient is not relevant. Rather, we suggest an intervention based on invalid or unsupported examination methods does not solely explain the outcomes observed from MT interventions. We reiterate the point that provision of MT is a systematic application of care that involves extensive critical reasoning to deliver an appropriate intervention. Developing these skills requires extensive training and practice. Self-efficacy develops as a secondary benefit of training and practice. Enhanced self-efficacy likely manifests in therapist confidence in patient handling and intervention delivery, which influences patient outcomes.
Pragmatically, it behooves us to ask our patients with pelvic pain what they expect from our treatment. Particularly helpful may be asking about prior treatment of the same disorder, as prior treatment success influences future outcomes in response to the same treatment.62 Conversely, a past negative experience with a treatment is associated with poor outcomes.63 If a person expects MT to help his or her condition or has had a previous positive response to MT for a similar problem, then incorporation of MT into the management is recommended. A patient not expecting MT to be beneficial and/or one who has had a poor response to MT may require more extensive education to try to modify these expectations should the provider feel strongly that MT is the indicated intervention.
Another element of expectations is identifying what the patient would deem an ideal outcome versus an outcome she would consider successful or an outcome she would deem satisfactory. For example, the ideal outcome for a woman with pelvic pain may be zero pain. She would, however, consider 75% pain reduction a success and would be satisfied with a 50% reduction in pain. Setting realistic expectations for outcomes and identifying patients' markers of success with treatment are integral parts of goal setting and developing a plan of care.
Consider also shared decision-making (SDM), which is a method whereby patients and providers work together to make decisions about management. The emphasis on understanding and incorporating patient preferences and interventions for which there are high expectations64 aligns with the points made earlier; that is, asking a person what he or she expects MT to help and incorporating that into a management plan improves outcomes. We are not suggesting, nor does using SDM imply, that the patient alone decides the management plan. Rather, communication with the patient about intervention options and the potential benefits and risks of each while including the patient's values and preferences in the clinical decision-making process is prudent.
Provider preferences and management styles should also be considered. This offers an alternative to SDM that requires collaboration among providers and an awareness of our biases for interventions. A person in pain who expects MT to help would be better paired with a provider who believes strongly that MT will be the best intervention rather than with a provider who avoids performing MT. While many of us recognize this, and occasionally implement it in practice, our observation is that this is rarely an overt component of management decisions. Such an approach is complementary to SDM in allowing the patient to work with a provider with shared preferences.
We must also consider how we present information that we provide to people seeking our care. A powerful example was shown by Thomas.65 Patients presenting with “common cold” symptoms but no definite symptoms or diagnosis were assigned to a “positive” or “negative” consultation. In the positive consultation, a firm diagnosis was given and the patient was told that he would be better in a few days. In the negative consultation, the patient was told: “I cannot be certain what is the matter with you.” Two weeks later, 64% of patients in the “positive” group reported symptom resolution while only 39% were better in the “negative” group.65 There are also many examples from the placebo literature, specifically enhanced placebo. Simply using the phrase “this causes pain relief for some people” causes greater pain relief in experimental studies.66 Collectively, these suggest the manner in which interventions are presented to patients influences outcomes. While clinical trials often contain scripted interactions to avoid biasing participants, clinical care is characterized by enthusiastic providers without such restraints. Confidently providing MT while informing your patients of the potential benefits is likely to enhance effectiveness. While maximizing expectations is the goal, expectations must be truthful and realistic, as unmet expectations may result in worse outcome.67
We must also pay attention to the narratives we use. People with LBP often view persistent LBP as due to the body being a “broken machine” and that back pain was complex and negative.68 Further questioning identified that people had learned these stories from health care professionals.68 Explanations that joints are “out of place” or “misaligned” cause uncertainty and increase fear avoidance in patients.69 These narratives are persistent in pelvic health physiotherapy practice as well. The use of unreliable tests and measures, including sacroiliac joint mobility testing, pelvic alignment, innominate rotation, and postural assessments, and others that comprise advanced training in pelvic and women's health physiotherapy fuels the narrative that women with pelvic pain have “misaligned” or “out-of-place” body structures that require fixing. Physiotherapists are seen as the experts by patients, and the stories we tell are more influential than other information the person receives about the condition, persisting with them for years.69
Recommendations about avoiding false narratives are seen in the various publications aimed at helping PTs present information about the nature of pain, pain beliefs, and recovery to people in pain.70,71 However, a recent trial comparing intensive pain education with equivalent time spent talking with about any topic of the patient's choosing showed similar outcomes for people with acute back pain who were at high risk of advancing to chronicity.72 Thus, the specific content of this education may not be as important as spending quality time with the person in pain, building rapport, and validating the person's experience. This aligns nicely with other work regarding the effectiveness of simple therapeutic communication for people with chronic pain disorders.73
Identifying and practicing a systematic approach to patient management in a therapeutic environment are of paramount importance. Patients value the improved handling skills resulting from experience and advanced training in MT. Technical skills in delivery of MT result in intervention effects independent of context. However, attributing outcomes completely to non–context-related mechanisms of interventions ignores a strong body of research suggesting otherwise and prohibits the careful self-assessment of our practice needed to maximize context-related influences on our intervention outcomes. Considering patient expectations and preferences when developing the management plan is not in conflict with any systematic MT approach and has the potential to improve outcomes for people with pelvic pain. In parallel, considering our own biases and preferences is important to determine if we embark on a SDM pathway with the person with pelvic pain or if we prefer to align practitioner beliefs with patient expectations. Finally, we must also consider the words that we use and the narratives that we tell, as these profoundly influence the person to whom we tell them.
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