Individual Expectation, a Pertinent, Factor in the Treatment of Musculoskeletal Pain
Written by Editor   
Wednesday, June 28, 2017 06:24 AM

Many factors in the treatment of patients with musculoskeletal pain are considered. The current literature suggests expectation is an influential component of clinical outcomes related to musculoskeletal pain for which physical therapists frequently do not account. The purpose of the clinical perspective reported here is to highlight the potential role of expectation in the clinical outcomes associated with the rehabilitation of individuals experiencing musculoskeletal pain. 

Interventions for musculoskeletal pain conditions often address impairments with the implication that pain and function will improve in response to stretching a tight muscle or strengthening a weak muscle. Realistically, the mechanisms through which physical therapy interventions alter musculoskeletal pain are likely multifaceted and dependent upon a variety of factors. The current literature indicates factors other than the correction of physical impairments influence clinical outcomes in the conservative management of patients experiencing musculoskeletal pain.

The purpose of this perspective article is to review the influence of expectation for the treatment of individuals experiencing musculoskeletal pain. Health care expectations may be positive or negative and are defined as the general belief a clinical outcome will occur. One model conceptualizes expectation as related to patient satisfaction. The model consists of 4 categories of expectation: 

(1)   predicted expectations or what the individual believes will occur,  
(2)   ideal expectations or what the individual wants to occur,  
(3)   normative expectations or what the individual believes should occur, and  
(4)   unformed expectation or the lack of a preconceived notion regarding a situation or intervention.

Predicted expectations are what the individual believes will occur.  The literature to date supports a relationship between measures of predicted expectation and clinical outcomes related to musculoskeletal pain. 

Ideal expectations correspond to the constructs of desire and hope. Ideal expectations are what an individual wants to occur, whereas predicted expectations are what the individual thinks will occur.  

Normative expectations, or what the individual believes should occur have not been studied extensively for their influence upon clinical outcomes related to musculoskeletal pain conditions. Patient satisfaction with a given intervention is related to normative expectation and unmet normative expectations may lead to dissatisfaction. Patient satisfaction with treatment for musculoskeletal pain is influenced by factors other than relief of pain or improved function. Subsequently, normative expectations may provide a better indicator of satisfaction for individuals experiencing musculoskeletal pain than as a prognostic indicator for outcomes related to pain and disability.  

Unformed expectations are those of which an individual is unaware or is unwilling or unable to express. For example, an individual may have no prior experience with a situation upon which to form an expectation for a corresponding outcome. Additionally, some actions may be habitual and not require conscious thought or subsequent expectation. Unformed expectations, to our knowledge, have not been studied extensively for a relationship to musculoskeletal pain conditions. 

Clinical studies have demonstrated an association between predicted expectation and outcomes related to the management of musculoskeletal pain conditions. Expectation also is associated with negative outcomes. 

In summary, studies suggest an association between predicted expectation and outcomes related to musculoskeletal pain conditions. Furthermore, these studies suggest a prognostic value for expectation in the treatment of individuals experiencing musculoskeletal pain that may surpass the type of treatment provided. Specifically, the exact intervention may not be as important as the individual expectation for the intervention. Outcomes, therefore, may not depend wholly upon the type of treatment provided, but also are influenced by individual attitudes or beliefs regarding the treatment. Manipulation of expectation, as is common in the placebo literature, suggests a causative effect of expectation on pain-related outcomes that may translate to the clinical management of musculoskeletal pain conditions. 

Researchers have suggested that expectation alters musculoskeletal pain in 5 ways

(1)   promoting a physiological response,  
(2)   increasing motivation to participate in a designated program,  
(3)   conditioning an individual to focus on specific aspects of a disorder while ignoring others,  
(4)   changing a patient's understanding of the disorder, and  

(5)   mediating anxiety to decrease or alleviate pain. 

The literature does not currently support a standardized measure of expectation. Subsequently, we are unable to recommend a specific measurement tool. Expectation is associated with outcomes related to musculoskeletal pain conditions, [16, 32, 45, 48] despite the variability in measurement methods and lack of a standard definition. Considering the current lack of a validated measure of expectation, we suggest that clinicians include a simple but consistent method of measurement. Additionally, clinicians should consider that negative expectations may influence outcomes related to pain, [82, 84, 85] so a scale encompassing no change to complete improvement may not reflect the beliefs of a patient expecting his or her pain to worsen. Consequently, clinicians may want to ask their patients to categorically indicate whether they expect their pain to worsen, stay the same, or improve. A 3-item scale may be sufficient in cases where general predicted expectation is preferred. When comparing expectations for 2 or more interventions, more options may be desired, and this question could be followed up with an appropriately anchored numeric rating scale, with 0 indicating no change and 10 indicating complete improvement or worsening, or a Likert scale with greater options. However, further investigation is necessary to identify reliable and valid methods of measuring expectation.  

Although the literature does not support a specific measurement scale, certain features of a measurement scale may be more useful in predicting clinical outcomes related to musculoskeletal pain. Predicted expectations (what the patient believes will happen) currently appear more reflective of clinical outcomes related to musculoskeletal pain and should be included as prognostic indicators. Clear instructions should be provided in order to differentiate predicted expectations from ideal expectations (what the patient wants to happen). For example, the patient should be told, “We would like you to indicate what you think will occur and not what you want to occur.” The request to the patient should be specific to an outcome and a time frame, as a greater relationship between expectation and outcomes related to musculoskeletal pain has been associated with these traits of a measurement tool. [5] For example, rather than just asking patients to indicate their expectations for their low back pain, a more responsive question may be, “At the end of 4 weeks of physical therapy, what do you expect will be the pain associated with your low back condition?”  

The question also could be specific to identified functional deficits pertinent to the individual patient. For example, “At the end of 4 weeks of physical therapy, what do you expect will be your ability to play golf?” The response to each of these questions could be quantified with a numeric rating scale, with 0 indicating no worse/no better and 10 indicating completely worse/completely better. Despite the variability in measurement, a fairly consistent relationship exists between expectation and clinical outcomes related to musculoskeletal pain. We present general guidelines for the clinical measurement of expectation; however, additional studies are necessary to identify valid and more responsive constructs and measures of expectation.  

Baseline expectation may assist in directing interventions for musculoskeletal pain. Clinicians may want to include individual patient expectation for a given intervention in the clinical decision-making process when considering appropriate interventions for individuals experiencing musculoskeletal pain. 

The authors of this report suggest three specific factors must be considered, which support promoting positive expectations: 

(1)   the intention of maximizing expectation is to help the patient,  
(2)   the literature suggests analgesia related to expectation may be enhanced with a positive instructional set, and  

(3)   the statement should not be deceptive.

Clinicians also should be aware when a patient has unrealistic recovery expectations, as fulfillment of expectations is predictive of outcomes related to musculoskeletal pain. They may also want to distinguish ideal expectations from predicted expectations. These constructs could be differentiated quickly and easily using the same measurement scale, with the request to answer based upon what the individual thought would occur (predicted expectation) and what he or she wanted to occur (ideal expectations). Differentiating predicted from ideal expectations has potential value for directing educational interventions with patients regarding the most likely outcomes resulting from an intervention. The discrepancy between predicted expectations related to outcomes of treatment and ideal expectations related to outcomes may factor into continued health care use by patients with chronic pain and subsequent increased health care costs.

These authors believe several problems exist regarding the current understanding of expectation. A standardized measure of expectation does not exist, resulting in a variety of measurement tools, with many lacking validation. Additionally, the construct of expectation has not been fully defined, and measurement tools assess varying components of expectation that may or may not be valid or comparable. Subsequently, methodological variability exists in current studies of expectation, and comparison of the findings of different studies is limited.  Psychological factors such as fear, catastrophizing, and depression may influence clinical outcomes related to musculoskeletal pain conditions. Furthermore, psychological factors may interact with expectation to influence outcomes. For example, a lessening of emotional distress is related to greater expectation-related analgesia. 

Expectation is associated with outcomes related to musculoskeletal pain and is a factor for which clinicians may not adequately account. Neither a standardized definition nor a generally accepted measurement tool exists for expectation; however, an association is consistently observed in relation to outcomes for musculoskeletal pain conditions. Expectation may serve as a significant prognostic indicator for individuals with musculoskeletal pain conditions, and the literature suggests practitioners may take steps to maximize the benefit of expectation in their daily practice.