Treating pain is a tricky business, but one that has become an integral component of today’s healthcare system.  As clinicians, it is a primary outcome measurement that we regularly hinge the successes and failures of our treatment on.  But is this the right measurement for all patient cases?  Is all pain the same?  Such questions quickly lead us down a rabbit hole and self-examination begging the question – Am I doing it right?

This blog will attempt to answer such questions and provide relevance to clinical practice.  In order to know if we are on the right path for treating patients with pain, we need to define pain.  An undertaking that is no easy task.

Examining the history of pain quickly elucidates our lack of understanding of the topic.  

Sullivan 2008

In 1662, Descartes describes pain based on dualism (Sullivan 2008).  He argues the forces governing our bodies are separate from the forces governing our minds.  In the above example he explains the flame would cause pores in the foot to open and tubes would drive spirits up to the brain.  Another way to view this, damage to the tissue in the foot activated neural pathways signaling the brain of the sensation of pain, eliciting a 1:1 of pain intensity and tissue damage.  Unfortunately, this remains a pervasive thought in the medical community.  

Building on Descartes original model, we can see the development of a biopsychomotor model.

Sullivan 2008

This model adds behavior to a previously dominant sensory system: communicative pain behaviors and protective behavior.  Communicative includes such things as facial expressions (grimacing) and verbal/paraverbal expressions (words such as owe, hurt, ouch and grunts/moans). The point of behavior systems is to relay pertinent information to observers about the painful experience of the sufferer in an attempt to elicit aid.  

Protective pain behaviors are any actions to mitigate further injury/damage, reduce the painful experience, and recover.  

Coupled together, the addition of communicative and protective pain behavior broadened our understanding of pain and our roles as clinicians – understand the painful experience and guide to recovery.  

However, the unfortunate flaw in this premise is pain does not always mean tissue damage or the need for escape and recovery. 

Fast forward to 2016 and a recent article by Williams and Craig proposes an updated definition of pain to again gain a new perspective on the topic.  They propose this definition: “Pain is a distressing experience associated with actual or potential tissue damage with sensory, emotional, cognitive, and social components.”  

When we synthesize down the components of their definition for pain, the desired outcome relates to survival.  

Pain and pain expression are naturally selected for to ensure the survival of our species.  Williams discusses the idea of pain expression well,

“Of necessity, vigilance to observed pain cues in others coevolved. The individual expressing pain would derive benefit if expression of pain were reliably followed by actions by observers that promoted recovery and survival; protection from danger; and aid in obtaining basic requirements (Prkachin 1997; Prkachin et al. 1983). If the person in pain might survive rather than not, and the cost to helpers is low, selection advantage follows as with other help and exchange of information – the currency of kin or reciprocal altruism.”  

Pain expression was naturally selected for.

One of our primary jobs as clinicians is to attempt to understand the expression of pain from the patient in front of us and change their painful experience.  The inherent issue with this aspect of our job, we as humans are not great communicators regarding pain and our own personal experiences and assessment of our internal environment (our bodies) is poor and often skewed.   

The expression of pain is made up of 3 components:  

  1. Subjective perception
  2. Learned response
  3. Observable expression

All of our behaviour is influenced by social context.  The patient’s reporting of their painful experience is based on their subjective perception of the issue.  We must trust what they are reporting (if they say their pain is a 10/10 then believe them).  We should also not question the observable expression of pain.  However, our influence can be best hedged at altering learned responses.  Learned responses can be derived from conscious and unconscious behavior.  Reinforcement learning explains this concept well – interaction with one’s environment through trial and error; exploitation of past experiences and exploration of new ones based on risk/reward.  In essence, we are altering the painful experience for the patient while aiding learned responses.  The experience lies within the cognition of the patient.  

Examining Williams and Craig’s definition more closely reveals cognition is composed of 3 variables – attention, memory, and language.

Naturally, a painful experience elicits an often reflexive response to escape. The desire to escape is mediated by several moderators:

Each moderator influences the intensity of the patient’s desire to escape from the painful experience.  An initial threat assessment is completed where the patient decides how threatening to survival is this issue.  Followed by drawing on past experiences.  Novelty can drive the desire for escape due to unpredictability of the situation – the unknown is scary and tends to increase our need to flee.  With a high threat value, novelty, and unpredictability comes the possibility of catastrophic thinking or the thought process of worst case scenario (webmd for pain = cancer).  Finally, the painful experience tends to increase somatic awareness or vigilance to the area of the body we are perceiving pain.

This process can perpetuate our attentional focus to the painful experience and ultimately pain will demand our attention.  However, we attempt to oscillate our attentional focus between the painful experience and a focal task while managing the aforementioned moderators for escape.  

Durnez demonstrates this concept well in a 2017 study, “Let it be? Pain control attempts critically amplify attention to somatosensory input”.  

Where does our help fit into this equation?

The function of pain is to demand attention and prioritise escape, recovery, and healing.  

Once the decision has been made to escape, we are sought out for our knowledge to aid escape and set the patient on the path to “recovery and healing.”

Once the patient is in our office, a primary directive is to change the painful experience. In order to do so the appropriate path requires assessment.  A dichotomy will be formed in order to ease the process of clinical decision making and provide a framework from which to work from.  

Two categories of pain can be developed: acute and chronic.  The determining factors of pain classification are related to the timeframe of pain chronicity and the presence of an identifiable mechanism of injury (MOI).  

A great example of acute injury resulting in acute pain is the 2008 Beijing Olympics.  An obvious traumatic injury for the weight lifter.  In the above picture, there is direct evidence of an MOI relating to tissue damage and the experience of acute pain.  

We have a fairly good understanding of the physiological process which ensues following such an acute injury. We can view this process as a bottom-up approach (Hauck 2015 and Nicolardi 2016).  

Screen Shot 2017-09-10 at 6.18.23 PM

The acute issue is driven by a stimulus – barbell eliciting tissue damage from failure to adapt to applied load → which stimulates nociception or sensation derived from nociceptors → elicits an intensity dependent (threat assessment) unintentional/automatic response (self-protective behavior to ensure survival).  An acute issue has the potential for the patient to experience pain and in this instance is necessitated to elicit escape and seek recovery in order to limit further acute tissue damage.

We will come back to this graphic in a bit.

For now, let’s address the acute issue.  Tissue was damaged, we know a normative physiological response will occur to heal the issue – so what is our job as rehabilitation professionals?

We can’t expedite the healing process but there are a few things we can do when guiding the path of an acute injury.  

  1. Reassure/Set expectations – this issue will get better (obviously there are limitations to our healing capacity and perhaps there will be conversations regarding a new “normal”)
  2. Create good environment for healing – discuss movements/activities to avoid while an area heals and then slowly reintroduce tolerable movements/activities over broad time
  3. Guide the path to goals – what area was damaged and what does the patient require of that area for activities of daily living and desired extracurricular activities
  4. Minimize dependency – this one can not be stressed enough.  A possible correlate to development of chronic pain is the idea pain control and healing comes from external sources thus perpetuating a state of learned helplessness.  

Some other areas of focus that will be required for athletic populations:

  1. Discuss programming leading up to injury – often a non-contact musculoskeletal injury is a training based injury (we’ve discussed this previously – read here)
  2. Reintroduce tolerable movement over broad time
  3. Discuss programming during rehab – here are the things we can do while that area is healing
  4. Discuss return to sport programming post-rehab.  The patient has been likely operating at subthreshold of previous baseline chronic fitness levels, strongly advised against immediately returning to training at those previous levels – read here).

And for an acute issue…….that’s it – nothing fancy, no thrills, just cold hard evidence based advice.  We are along for the ride just like the patient but while along for the ride let’s guide the path to desired outcomes.

If an acute issue can be related to tissue damage and the painful experience then what is a chronic pain issue?  

Chronic pain is often referenced in the literature as pain lasting longer than 12 weeks and likely has little to do with actual tissue damage.  Juch et al 2017 demonstrates this well with the article, Effect of Radiofrequency Denervation on Pain Intensity Among Patients with Chronic Low Back pain.  The study aimed to evaluate effectiveness of radiofrequency denervation in addition to exercise vs exercise alone.  Radiofrequency denervation attempts to prevent the conduction of nociceptive signals by utilizing an electrical current to damage nerve conduction.  The authors’ primary outcome was pain intensity.  Authors’ Conclusions:

“In 3 randomized clinical trials of participants with chronic low back pain originating in the facet joints, sacroiliac joints, or a combination of facet joints, sacroiliac joints, or intervertebral disks, radiofrequency denervation combined with a standardized exercise program resulted in either no improvement or no clinically important improvement in chronic low back pain compared with a standardized exercise program alone. The findings do not support the use of radiofrequency denervation to treat chronic low back pain from these sources.”

What does all this mean? More support that in the cases of chronic pain – it is unlikely any specific tissue is responsible as a “pain-driver”.

Screen Shot 2017-09-10 at 6.18.23 PM

Shifting back to this graphic, chronic pain can be examined from a top down approach.  Pain is interpreted in the brain and subjective to the person’s experiences and perception of the perceived issue.  Chronic pain is often task specific, meaning a painful experience becomes associated with particular movements (example would be a person bending over to pick an item up from the ground and experiences low back pain).  How chronic pain develops is not yet fully understood but strides are being made in the research field.  For an indepth look at the transition of acute pain to chronic pain, check out this article by Chapman and Viereck 2017.  

One primary issue that faces the entire field of healthcare and quite possibly has contributed heavily to the opioid epidemic is how we frame chronic pain issues to patients.  

Attempting to apply a biomedical lens to the situation places the patient in a diagnostic box that can have long lasting negative effects.

Since we know chronic pain has little to do with actual tissue damage, assigning a structural label to the issue does not make sense (albeit necessary for most insurance companies).  Applying such a label can be quite damning to the patient’s psyche. Cohen 2011 discusses the issue as a stigmatization of the patient which impedes our ability to be empathetic to the person.

Stigmatization is defined as,

“Process by which the reactions of a community to a specific personal characteristic(s) reduces a person’s identity from a whole and usual person to a tainted, discounted one, causing that person to be discredited, devalued, rejected, and socially excluded from having a voice.”

Instead of focusing our attention on the whole person, we become fixated on the scarlet letter (diagnosis) the patient bears on their chest.

All of our efforts become dedicated in mitigating the person’s pain.  Better put, we attempt to control their pain instead of viewing the whole person in front of us.

Attempting to gain control over the patient’s pain likely will lead to misguided problem solving resulting in unnecessary (possibly excessive) use of interventions and amplification of the patient’s worry about their perceived issue when improvement isn’t reached.

The intensification of the patient’s worry may perpetuate their distress and disability snowballing into a hypervigilant state of awareness to their pain.  Durnez et al comes to the conclusion –

“The reported findings thus–preliminary—suggest that interventions, designed to directed patient’s focus away from pain control and towards acceptance are a step in the right direction.”

Acceptance of pain – A novel approach that would likely diminish the need for many non-efficacious treatments aimed at simply mitigating pain.  

This approach is gaining traction as discussions have been ongoing about the removal of pain as the 5th vital sign.

Perhaps we are not asking the right questions in rehab.

Sullivan 2006 questions the efficacy of regularly asking a patient about their pain level in the article, The Influence of Communication Goals and Physical Demands on Different Dimension of Pain Behavior?

Pain demands attention, and if we are consistently polling our patients about their pain levels then we are likely reinforcing their attentional focus to pain, perpetuating a hypervigilant state and somatic awareness.  

Now that we’ve discussed framing the issue, what can be done to treat patients dealing with chronic pain issues.  

Many of the topics addressed when dealing with an acute pain issue will also be covered when treating chronic pain.  

  1. Reassure/Set expectations
  2. Violate beliefs
  3. Decrease Kinesiophobia
  4. Aid with catastrophic thinking
  5. Guide the path to the goals
  6. Minimize dependency.

As clinicians, we are tasked with setting patient’s expectations. As we discussed in acute pain issues, this can simply be the reassurance the issue they are dealing with will improve.  Improvement is specific and meaningful to the patient.  This could mean pain improvement or functional improvement.  Research is elucidating three ways in which expectations can be set to improve outcomes: verbal, imagery, and classical conditioning.  Peerdeman 2016 and 2017 discuss how each component for setting expectations can relieve pain.

Peerdeman discusses simply suggesting verbally to a patient treatment outcomes will consist of analgesia sets the expectation pain relief will be achieved and thus the expected outcome is reached. Similarly, classical conditioning (pairing of neutral stimulus with unconditioning stimulus leads to a particular response) aids with pain relief.  Peerdeman provides the example,

“..pairing a placebo treatment with reduced pain stimulation can produce expected and experienced pain relief when merely receiving the placebo treatment.”  

In other words, verbally suggesting a treatment will relieve pain and then classically conditioning the patient to the treatment increases the likelihood the expected outcome (analgesia) will occur.  This certainly calls into question the ethics of what a patient becomes classically conditioning to.

Finally, Peerdeman demonstrated mental imagery can also have an effect on pain reduction.  Mental imagery is defined as purposefully thinking about a desired outcome or future event.  

In a 2017 study, he demonstrates:

“Placebo-like expectancy effects on pain can be induced not only by instructions, direct experience, and observation of other people, but also by mental imagery of a response (simulated experience).”  

So, imagining pain reduction before an experience deemed a provocateur of pain, likely will have an analgesic effect.

Setting expectations is one of the most important, but often underutilized, aspects of our jobs as clinicians.  

Next up are kinesiophobia, fear-avoidance, and violating beliefs; these three objectives can be rolled into one.  We as clinicians often set the tone for movement parameters during rehab.  The unfortunate mistake many of us make is setting these parameters too strictly.  In doing so we can perpetuate kinesiophobia.  Kinesiophobia is defined as, “An excessive, irrational and debilitating fear of physical movement and activity resulting from a feeling of vulnerability to painful injury or re-injury.”  

Text neck is a great example of how we can be well meaning with the delivery of a poor narrative.  Sure, staring down at an iphone for 3 hours straight will likely manifest some muscular discomfort but that doesn’t mean a person should never look down but instead would be better served to change positions regularly.  Similarly is the discussion of posture (we’ve talked about this previously – see here).  We’d likely better serve our patients by providing multiple alternatives of completing a movement rather than acting as the Procrustean arbiters of movement.

The Tampa Kinesiophobia Scale is an outcome assessment that can be utilized to assess apatient’s beliefs about movement.  Bunzil et al 2015 did a qualitative analysis study on the TSK and found two beliefs that can be assessed with the form: 

  1. Painful activity will result in damage
  2. Painful activity will increase suffering and/or functional loss

The TSK can provide integral information that can allow for educational opportunities with patients in order to reframe these limiting beliefs.

Kinesiophobia directly ties into the fear avoidance model of treatment.  Vlaeyen 2016 discusses the development of fear avoidance behavior based on how a person approaches a task.  Fear is defined as,

“The anticipatory emotional response to imminent threat, and adaptive learning takes place rapidly, either through direct experience, observation, or verbal instructions.”    

The fear avoidance model states chronic pain development can be perpetuated based on how the person approaches a task: obstacle or challenge and whether they view it as a high threat or low threat.  Here is where we can begin aiding patients with task specific learned responses.  If a patient experiences a noxious stimulus interpreted as pain and that experience is viewed as a high threat then the patient will likely prioritize pain control as their primary directive.  Given the experience has been labeled a high threat, it is likely the patient will assign a negative affect (emotional association) to the task and view it as harmful to their body.  An experience attached with pain, high threat value, and perceived harm to the body will perpetuate a cascade of fear → avoidance → interference → negative affect → leading back to pain. This cycle will likely lead many patients to completely disengage from any experience previously viewed as painful.  

We can aid patients in relearning a response to a particular task by regressing a movement/task to a low threat environment.  Transitioning a patient’s response to chronic pain from high threat to low threat will require some time violating beliefs and setting expectations.  With education, exposure to the situation, and time the patient can shift their understanding and response to a low threat value; allowing the situation to be viewed as a challenge rather than an obstacle. Once the patient views the previously painful experience as low threat, they can prioritize life goals while assigning a positive emotional response to the situation.  The patient’s optimism of the situation will then allow them to adequately approach a challenge, complete the task, and recover afterwards leading to an altered learned response.  This is also a great reason why chronic pain patients, within reason, can perform rehabilitative exercise into pain.  A study by Smith et al 2017 discusses the topic of exercising chronic pain patients into pain. Their overall findings revealed a small benefit in the short term (less than 3 months) but no medium or long term effect.  Given chronic pain has little to do with biomedical problems, this is likely a result of instilling the mindset of acceptance of pain rather than being controlled by pain. Reducing the mentality “hurt equals harm”, and mitigating kinesiophobia and fear-avoidance while building self-efficacy. An easy way to assess fear avoidance behavior is with the Fear Avoidance Behavior Questionnaire (FABQ) from Waddell et al 1993.

Another component of treatment for chronic pain based issues is addressing pain catastrophizing.  Sullivan 2001 discusses pain catastrophizing and defines the issue as follows,

“Catastrophizing has been broadly conceived as an exaggerated negative ‘mental set’ brought to bear during actual or anticipated pain experience.”

Catastrophizing has been demonstrated to:

  • Heighten pain experience
  • Be predictive of future pain experiences
  • Increase pain intensity
  • Increase duration of hospital stay
  • Increase use of analgesics/OTCs
  • Increase visits to clinicians, and
  • Heighten perceived disability

Three major components of catastrophizing include magnification, rumination, and helplessness.  

Magnification means the patient’s perception of the experience will be amplified – which is more reason for us as clinicians to remain calm throughout the process and reassure while setting expectations.  Rumination implies the patient will perseverate on the topic of perceived issue and pain will often be the primary focus of daily attention. Helplessness is one of the strongest arguments for utilizing treatments designed to build an internal locus of control of the patient.  We discussed this topic earlier in the blog regarding learned helplessness.  To reiterate, the patient believes pain and their situation is not within their control and requires outside assistance.  This further demonstrates why a primary part of rehabilitative treatment for chronic pain should minimize dependency.

An easy outcome assessment to administer for catastrophizing can be found in the Pain Catastrophizing Scale User Manual.  

Now onto the nitty gritty of treating chronic pain.  Typically chronic pain will follow a standard regression to the mean presentation.  Regression to the mean has been discussed in a previous blog (read here) but is worth revisiting.  

Whitney 1992 discusses the concept of regression to the mean and demonstrates a typical timeline of chronic pain.  

Patients seeking treatment for a painful issue will usually do so when their pain exceeds their subjective tolerance level after a painful event  – think of this as the patient who comes in “throwing their back-out” a few times a year.  The patient will seek care hoping to find pain relief but based on cyclical variation of pain, their pain will likely reduce back to baseline regardless of what is done during their peak pain experience. Statistically we discuss this as regression to the mean because if a variable (pain) is at its extreme during the first measurement (initial consult) then there is high likelihood upon the second measurement the variable will be closer to average/baseline.  Regression to the mean will mask true effects of a treatment modality and demonstrate false efficacy for utilization.  

However, all is not lost.  There are plenty of things we can do as clinicians while regression is occurring, Whitney articulates this well –

“Among patient groups in whom significant regression to the mean occurs, the natural process of improvement may provide opportunities to reinforce patient self-care behaviors and enhance patient beliefs in their own abilities to control pain, rather than reinforcing patient beliefs in the efficacy of medical care for chronic pain.  If so, the phenomenon of regression to the mean may have the potential to enhance patient autonomy in managing chronic pain just as it may now contribute to the dependency of pain patients on health care providers.”

We can’t discuss treatments without bringing up placebos and nocebos.  

Testa 2016 discusses the topics of placebo and nocebo and the associated determining factors in the paper, Enhance placebo, avoid nocebo: How contextual factors affect physiotherapy outcomes.  

A placebo translates to the phrase, “I shall please” and has been previously defined as an inert substance incapable of eliciting actual effects.  However, placebo likely requires a revamping as research continues to elucidate their is a placebo effect that occurs (regardless if a population is aware the substance is placebo or not) and likely leads to analgesia. Testa states a placebo,

“….is created by a positive psychosocial context capable of influencing a patient’s brain.”

 Placebos have been prevalent throughout the history of the medical field.  As discussed by Geuter et al 2017,

“Placebos—sham medical treatments—have been used throughout the history of medicine to ‘gratify’ patients.. Egyptian patients were treated with balms as various as lizard’s blood, crocodile dung, and the teeth of swine. According to Shapiro, industrial-age Europeans administered equally colorful treatments, ranging from animal (earthworms, wood lice) to uniquely human (saliva of a fasting man, powdered mummy). Naturally, it is only with the hindsight of modern medicine that we recognize these treatments as shams; but we are not immune to using sham treatments even today. Notable sports stars regularly use so-called energy bracelets and necklaces to improve their performance. Widely used procedures like arthroscopic knee surgery and spinal steroid injections have been found to perform no better than placebo (Bicket et al. 2013, Moseley et al. 2002). And physicians still prescribe placebos regularly (Linde et al. 2014), presumably for the same reasons as they have throughout history: to provide care and convince the patient, and the world, that things will get better.”  

Placebo effects are going to occur because a patient is seeking knowledge from a position of perceived authoritarianism – the question becomes can we ethically maximize the effects without creating a dependency.  A new phrase that has began emerging in clinician narratives is neurophysiological effects.  Finniss et al’s 2010 paper makes neurophysiological effects sound a lot like placebo effects.  Again, we likely need a new definition for these two terms placebo and neurophysiological.  I’m a biased fan of this definition,

“Any primed non-threatening sensory stimuli to the nervous system affecting the patient’s psyche which elicits a desired outcome.”

Returning to ethics, any modality geared at enhancing the placebo/neurophysiological effect and increases likelihood of creating patient to clinician or patient to modality dependency should be minimized not only for financial loss but also loss of time (a commodity we can not manufacture).

On the opposite end of the spectrum are nocebo effects.  Nocebo translates to “I shall harm” and Testa states these effects occur as “….the result of negative ritual and therapeutic act on the patient’s mind and body”.  These can likely perpetuate hyperalgesia.  Utilizing a modality for chronic pain geared at pain reduction can create a false dependency and perpetuate learned helplessness likely having nocebo effects.  Nocebo effects occur from such interventions because patients develop the belief without those treatments relief will not occur and their only solution is being taken from them.  If we continue to treat chronic pain as something from the outside is required to “fix” the issue then we are perpetuating an external locus of control and unnecessary use of interventions; robbing patients of time and autonomy, equalling harm. Harm is multifaceted and not simply increasing symptomatology.  The belief a modality is needed for relief can perpetuate symptoms long term.  Our attention would be better served aiding patients in learning self-care while instilling an internal locus of control.  

As clinicians attempting to accomplish long term outcomes and patient independence, we should take great care in minimizing these unnecessary effects.  

Finally, a keystone to treating any pain based issue is our therapeutic alliance with the patient.  

Martin 2000 defines therapeutic alliance as,

“The collaborative and affective bond between clinician and patient.”  

The quality of the therapeutic alliance is more important than the type of treatment selected in predicting positive patient outcomes.

There are three components to therapeutic alliance:

  1. Affective bond between clinician and patient
  2. Patient’s and clinician’s ability to agree on treatment goals and tasks
  3. Collaborative nature of the relationship

Coupled together, these components strengthen our therapeutic alliance with the patient and allow for a team based approach to be taken towards meeting the patient’s goals.  

In summary, treating pain is a tricky business BUT we are starting to understand the complexity of the issue.  

This blog is by NO means a complete guide to pain science and we strongly encourage all readers to regularly read current best research evidence on the topic.  

If there is a primary takeaway from this blog – OUR WORDS MATTER.

Words are our most important tool in our toolbox and they will reach far into the future, well beyond any other modality.  All the more reason to ensure we are delivering the most current best research evidence on the topic at hand and minimizing the delivery of false narratives.  

As always, if you want to discuss the article with us on Twitter, or just recommend a beer for us to try you can find us at:

@DMilesPT

@MichaelRayDC

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