In rodents? ICSS

A behavior test is the best ways to assess pain in an awake animal. Some assessments are based on a withdrawal reflex (foot, tail) to heat or mechanical stimulation, others, on pain-related behavior (crouching, grimaces, vocalization, etc.).

There is a strong difference between pain sensation ( measured by objective assessment - vas, nrs, behavioural scale ) and pain perception and elaboration by association subcortical areas ,that have the properties of prolonging pain sensation and explaning pain chronicitation , sufference and catastrophing style , all assested by psicological tests

The best way to assess pain is to ask the patients about his or her experience of pain. Self-report is the gold standard of measuring this symptom. You can use tools such as the 0-10 numeric rating scale to assess pain intensity. A number of different questionnaires measures different dimensions of the pain experience, such as pain interference with function (physical and affective functions), pain descriptors or qualities (affective and cognitive dimensions), time pattern of pain, factors that relieves or exacerbate pain, and so on. In fact, we do have more tools to assess the pain experience. Nociception - that is activity in the nervous system that may lead to a pain experience - is really hard to assess! Microneurography can measure activity in peripheral nociceptors, but this method is complicated and very time consuming. In the clinic we only assess pain - never nociception.

I appreciate all the answers - and more are still welcome.

I think it is important to assess both. It is not an either / or issue. Nociception is the data of pain, and the initiation of the great majority of instances of pain. Nociception is the primary baseline sensation whereas pain is the conscious experience of nociception. Some pains are almost entirely nociceptive and other pains persist long after nociception has ceased i.e. the pain becomes neuropathic as a primary central nervous system anomaly. Knowing the nociceptive origin of pain will tell you where to direct therapeutic care to stop the initiating stimulus for pain. Knowing the neuropathology of pain will tell you where to direct care to alleviate conscious suffering. You cannot stop suffering while nociception persists unabated, and you cannot stop suffering if the nervous system and the consciousness persists in inappropriately magnifying and distorting the nociceptive input.

Good pain therapy consists of learning what component of the overall complaint is nociceptive and how much is central nervous system dysfunction. In most simple cases, dealing with the nociceptive input is sufficient to achieve excellent long lasting pain relief. Pain can become persistent for basically two reasons 1. the nociceptive input persists through repeated tissue damage or because the nature of the pathology is that it does not spontaneously resolve 2. The central nervous system and consciousness develops a pathological pattern of processing nociception.

In persistent nociceptive activity, a proper history and physical exam, augmented by imaging and other physiological testing as needed, and is usually sufficient to determine the source and cause of pain. If a therapy exists, then treatment follows logically enough.

In persistent pain which is not primarily nociceptive there are many different possible aspects to consider, and this has given rise to the whole pain therapy industry. There are the central nervous system aspects that operate below the level of consciousness , such as cases like phantom limb pain and CRPS. These are primarily pathologies of the subconscious CNS. However the CNS and consciousness are obviously intimately related and so pathologies of consciousness often play an important part in maintaining the pain experience. Fear avoidance, cognitive errors, erroneous beliefs about the meaning of pain, incorrect habituated responses to pain, cultural beliefs etc, may all need to be evaluated. Those aspects that reflect pathologies of consciousness may be assessed using standardized and validated questionnaires, and appropriate interviewing techniques. The CNS pathologies are assessed through history taking and physical examination. There is a neuropathic pain questionnaire that I know of but have not used much and I can share if desired.

I reiterate my initial statement. It is important to consider both nociception AND the pain experience. If you treat only nociception you will have successes where this is the primary concern, but fail, even if you correct the causative pathology, when the CNS and consciousness issues play an important role. The reverse is true as well. A patient with a persistent nociceptive type of pain will not thank you for your deep and meaningful discussions on the psychological and cognitive aspects of pain. There is a continuum here which on the one hand is almost entirely nociceptive in character, and on the other hand is almost entirely neuropathic and psycho-emotional. An individual patient may be classified as existing anywhere along this continuum and this position on the continuum does not necessarily remain stable. Also all cases of pain are not evenly spread along the continuum. In primary care and ordinary life, most cases of pain are towards the nociceptive end of the continuum. In tertiary care clinics, especially pain clinics, maybe a majority are towards the neuropathic / psycho-emotional end. I would also recommend that duration of symptoms is not a reliable guide to where on the continuum the patient is likely to be. There are acute cases of CRPS for example, and there are many patients with years of persistent pain that remains almost completely nociceptive in character. There is an association between symptom duration and the CNS / psycho/emotional end of the continuum, but we much continually remind ourselves that an association - even a 1 to 1 association - is not the same as a causal relationship.

Once again thanks for all your qualified answers. I would like to expand my question a bit. Say pain is a first-person experience. Is nociception/sensitisation then always the equivalent third-person perspective?

One example is "heart ache", which to my best knowledge does not have any nociceptive component albeit no person who has lost love would say that sorrow does not hurt. Luckily these pains seem be acute in their nature...

A completely different example is torture, which in some cases can be caused without any known tissue damage or nociceptive origin. However these pains tend to be long lasting and highly disabling.

Although these two examples have no apparent similarities it could be argued that they both are created in the social domain as opposed to the sensory.

This is not to say that there is no biopsychosocial interaction but to highlight the lack of knowledge (as I see it) regarding pain of no obvious nociceptive origin.

If we can test for pain and eliminate the nociceptive role or visaversa it would be interesting to do so in such cases to shed some light on the social role of pain.

I appreciate any comments. Thanks!

@Morten

I think it is very important to separate out clear instances of emotional distress from pain. What I mean is that 'pain' in the case of 'heartache' is clearly an emotional state whereas toothache from an infection is almost entirely nociceptive. Whilst the word 'pain' of the heartache kind can have somatic elements (a hollow feeling in the chest or stomach), it seems to be generated directly from consciousness in the form of (in this case) an experienced threat to something regarded as extremely valuable (a cognitive assessment) i.e. the relationship with the object of one's romantic desire. Conversely the toothache pain is almost entirely nociceptive, but can have psycho-emotional element e.g. worry about the cost of the dentist, or the spread of infection etc.

The big difference between somatic pain and emotional pain is that somatic pain is expressed in terms of spatial orientation i.e. a toothache is in the tooth and jaw, backache is in the back. These pains have a nociceptive element, at least initially. The 'heart'ache you refer to usually refers to the sufferer's object of romantic desire, not to the physical structure - the heart. An ache in the heart (as an organ) - has a special word - 'angina' - which has a very specific clinical pattern of presentation. To re-iterate, the pain I was referring to in my previous post is the one that is most usually expressed as having a specific location in the sufferer's body, whereas emotional pains such as 'heartache', grief, worry, anxiety etc are not so expressed.

To confuse these two senses in which pain may be used linguistically is to equivocate.

Does this help?

Dear Morten,

Where exactly do you want to go to? The social role of pain? That would not be the (subjective) experience of pain, but the social detectable expression of the experience.

First I would like to argue that the experience of pain is ALWAYS constructed of bio-psycho and social aspects. You never can leave one out. In the example of the heart ache, assumably some proprioceptive information will be labelled as pain. So there's a bio aspect also. For some reason what we always do is want to find out which aspect is most important. We should not do that. It is like in a car saying that the wheels are more important that the engine. Lose one of both and you can't drive.

It always is the interaction that creates pain. And yes maybe in some cases some aspect may be predominant. Why do we need this? For example to figure out how to act to diminish the pain.

If we talk about the social role of pain this is a different territory. For example: Animals respond to nociceptive input. It can be questionned whether they have the same emotional experience (or should I say labelling) to pain as we have. I won't go into this discussion. Nevertheless, the behaviour of the animal because of the nociceptive input is observed by other animals: the relatives may be warned for danger, predators may become more agressive because of the potential meal.

These same social responses will be found in humans.

On the other hand there is the experience of the subject on the social response on his/her pain behaviour. (do you still follow?) Here much learning processes take place:

Example: positive responses to pain behaviour depending on the situation can be either enforcing or damping the behaviour: A child in pain beeing caressed by his parents may learn that the pain is not severe and feels comforted. Next time the pain response will be less. However if the child for some reased needs more comforting (beeing insecure or so) it may enhance the pain behaviour as a tool to get more attention. These are two opposite learning effects based on social repsonse to pain.

So Morten, where did you want to go with the social role of pain?

Dear Mark and Jan-Paul (and everyone else on this thread)

Once again a huge thanks for your comments which I find very interesting. Let me try to answer the question you ask, Jan-Paul: Where do I want to go?

I find pain to be an intriguing phenomena, and I´m not sure I share the fundamental idea that you, Mark, put forth by distinguishing emotional pain from somatic pain although I admit it does seem to be the most used paradigm within the field.

I believe pain to be a universal but individual experience. By this I mean that the same stimuli will never be able to cause the same pain again and again, however, a pain can be experienced in the same way more than once relatively independent of the stimuli. Obviously this argument should be broken down and explained piece by piece but I´ll rather not go there for now.

Assuming that to some extend pain is individual yet universal it would be plausible to assume that - all things equal - a person could experience pain without any nociceptive stimuli. This is not the same as discarding "bio" in the biopsychosocial model.

Most pain researchers and specialists would agree that the "bio" and "psycho" are fairly well understood, but that the role of "social" is either a part of the psychological/behavioural construct or neglected.

So my first question was ment as a way to find out if anyone uses less traditional methods to investigate, document or assess pain.

To answer your question, Jan-Paul, I´m curious to learn if there is a potential in understanding the social aspects of pain which can help clinical scientists to address pain rather than nociception in patients? And could this potentially enhance not only our understanding but the effectiveness of our practice.

Dear Morten,

I think we agree that pain is a subjective emotional experience. Making the leap to social implies that we talk about communication. As part of communication the subjective emotion of pain can be expressed. How pain will be expressed depends on numerous (bio-psycho-social) factors. Furthermore this expression of pain is part of a learning process driven bij Interactive social responses. I think therapeutic aproaches like graded activity use these principles.

Although I agree with you that changing the social behaviour (communication) around pain could alter the experience in itself, the pain experience remains the subjective emotional experience. So what I would suggest is that you use regular measuring methods for the subjective pain experience (like the VAS) but try to combine this with determinants of social interaction.

Final example: compare pain to hunger: you can express the fact that you are hungry. People will respond (agree, give food, tell you to stop whining etc) this may alter the perception of your hunger, but it remains your interpretation of what you feel inside. Hunger communication is very distinct from the emotion hunger!

Dear Jan-Paul

I´m intrigued by the idea that social interactions occur via communication. It´s not how I´ve thought of it before. I´ll give it some more thought! Thanks for your supportive ideas.

Kind regards,

Morten

Dear morton

How else would social interaction take place??????

Dear Jan-Paul,

I´ve not thought of social interaction as communication although it to some extend make it much more "handleable". Depending on how wide the definition of communication is taken I believe that any social interaction will affect us. Most people consider isolation a penalty which is likely to affect us in many ways (molecular to personality and meta-cognition).

Social interaction could include much more that mere verbal communication and body language. The role of sensory stimulus i.e. touch is one example and culture and cultural paradigms another.

Obviously pain science can learn a lot from sociology, anthropology and philosophy in the sense that pain (the first-person perspective) is very difficult to study with natural sciences alone. I believe we need to move forward using new methods as suggested by Varela and Thacker (First-person neuroscience).

Hi Morten,

I don't want to be annoying but isn't touch another form of non-verbal communication? And how do we become aware of cultural paradigms. It occurs to me that this has to be in any form of communication.

Indeed you have a point that it is difficult to capture the experience of pain in 'objective' parameters. It is in a way the same thing as knowing colours. We talk about blue and point at the same coloured items, but what exacly do we experience? This is a very challenging (and very philisophical) issue.

Endeed! How would you go on about it? Communication or not - I think we should be focused on assessing pain - not only nociception. But we need tools to do so. If communication is one way - then how do we assess or measure the value or effectiveness of communication (valid and reliably)?

It´s a very interesting subject - but not easy to put into science or clinical evidensbased practice...

Dear Morten, I think communication IS the problem. You know the saying: 'lost in translation' ? That is what I am thinking of. The moment a subject tries to value, label, express or explain the sensation there will be loss of information. In my previous example on colour: we can agree on what we call a certain colour, but how can we be sure we experience the same?

The question is what exactly you want to achieve? A mother doesn't need exacly to know her childs pain to know it needs comforting.

On the other hand, considering the almost spiritual aspect of you question (what is it that has the experience, the soul?) I really wonder if this path is practical for daily use.

Dear Jan-Paul,

Clinically chronic pain is a huge problem as you already are aware of. The better we understand "pain" the more direct I suppose we can interact with the patient. Say communication gets lost in translation we might need to learn how to address this from a professional point of view - not "just" as an intervention but also in terms of measures that can provide data for research.

Hi Morten,

I understand what you want to achieve, but I still don't understand why.

Could you explain what we could improve if we almost feel the same thing the subject is feeling (I think it would get down to that if you want to go to the first person experience...) For now it seems to me like a path you can follow in a technical sense (is it possible to...) but you have to tell us some more about what the therapeutic consequence could be? Can we prescribe better medication? Can we do better exercises?

What I just realize: if we succeed in what you are trying to achieve wouldn't that mean that you would feel the same thing the patient is experiencing. In other words, their pain? I think I would have to end my therapeutic carreer really quickly...too much pain.....

Finally, what we now do is 'measuring' a patients pain experience by using for example the VAS scale. In doing so we accept the fact that this is only a subjective and abstract reflexion of what the person is feeling. (and we cannot even tell if it is true) Both therapeutically and scientifically this seems fairly acceptable. It would be nice if we could measure a level of or location in brain activity and say that corresponds with a level x of pain. Untill now that brain spot has not been found. Neither has the location of our soul.....

True :-) And we will not fint that spot ever if you ask me. I also don't believe it is or ever will be possible to experience someone elses pain.

However, to understand the difference between 'pain is always caused by nociception' and 'nociception may or may not play a role in pain' will make a huge therapeutic and scientific difference. So part of my question is to address this issue as well because pain much too often is only associated with pain.

The other issue of which I'm very interested is for professionals to understand the patients. Take communication as an example: It sometimes seems provocative to question the patients experiences i.e. VAS 80/100 when they don't appear to the HCP to be in pain. Therefore I believe many clinicians don't go into this but conclude on data that does not make any sense.

Wouldn't be preferable if we were able to dig into and understand the patient?

In order for this to happen on a broader scale i.e. a paradigme shift we will have to understand if it's worth the effort. And to do so we need to be able to collect data and document any significance it i.e. communication or social interaction may have.

I don't believe VAS is sensitive to this and neither is any other tool that I know of.

Dear Morten,

Not easy, but I think I am getting closer. Back to the egg:

1. Pain is a subjective emotional experience.

2. The emotion pain is the result of complex interaction of 'ception', not necessarily nociception, the neural responses, level of awareness and cognitive labelling.

3. The relative contribution of the under 2 mentionned aspects can differ.

4. Communicating pain is difficult because we have to deal with a subjective first person experience that can hardly be transferred.

5. We find discrepancies in patient behaviour and how they score their pain level.

(scoring 80 of 100 but smiling and seemingly happy)

6. We conclude that subjective experience, and the patients communication are not (always?) 1:1.

7. What you want to explore is what is causing this non-relation.

My first thought is: they are (deliberately or not-deliberately) lying. Or in more therapeutic words: they feel reasons to score their pain on another level than they actually perceive. But I realize, this is to easy. Could it be that there are patients that experience pain on a high level, but on the same time keep smiling and be active? And don't forget the opposite: patients with low pain scores but with severe physical impairments.

In this perspective you raise a difficult question. What you need is to find ways to quantify the under 2 mentionned aspects and correlate them with subjective representations of pain (like VAS). I can imagine under laboratory circumstances applied noci input, measuring stress levels, and the subjects ideas on the test (how dangerous/harmful is it)?

Another way could be to see if or how a patients communcation changes when other interests are at stake. It could well be that some studies have been performed in this field.

One additional note:

I disagree that VAS scores are not sensitive to extra intentions of the subject.

First: a VAS (pain) score is no more than the communication of the patient how he/she wants the world to know (!) how he/she feels the pain.

Interestingly, if we also ask a minimal and maximal painscore we get extra information: the VAS (now) should be somewhere in between of the VAS min and VAS max. It would be very coincidental if at the moment of scoring the VAS now equals or even is less than the VAS min. Likewise if the VAS now is equal or even higher than the VAS Max. In these cases it is the assumption that patients are telling us something about their pain experience: in the first case it can be assumed that the patients has problems to face the actual pain. These patients easily overburden themselves. At the high pain levels patients feel the urge to convince the world that they are really in pain and really need help.

These ar crude indications that always need testing, but is adresses you goal Morten....understanding more on how the patient communicates his pain.

There is literature on this, but from a long time gone. Maybe some other reader can help us out here.....

Dear Jan-Paul, thanks for an interesting and inspiring dialog. No doubt we could keep this going for a long time... But I´m keen to see if anyone else have comments on this?

@ jan-Paul

I agree with you comments on the VAS. It is a good measure of a single dimension of pain - pain intensity as perceived by the sufferer. I also agree that the use of VAS's for different times is important and I use three: a 100mm VAS for 'pain at its best in the last 48 hours, pain on average in the last 48 hours, and pain at its worst in the last 48 hours. I agree and also use a VAS for pain intensity as it is now - which is a measure of the exact current status when the patient has the opportunity to describe their experience to a clinician. Sometimes the discrepancies are very revealing. For example the patient might say the the pain is 80/100 at best, on average , and at worst, i.e. is unvarying, yet they will also claim that the pain is worse sitting and better standing. There is a contradiction here but I have had many patients who are not aware of it. his might be considered a 'yellow flag'. The relationships between the VAS scales and other data is what counts I think

What do you think of variations of the Patient Specific Functional Scale? Depending on how VAS is used (what the dichotomy of the scale represents) it may not reveal anything but the intensity of distress?

However, disability which I consider a major part of chronic pain is not specifically measured by VAS or any other Likert-scale-variation. Do you think a combination of a Likert-scale and patient´s perceived disability represents a valid 'pain' description?

The PSFS is a good measure of function - it measures another dimension entirely of course, though there is always overlap between different measures. Some aspects of the VAS will inform about function and some aspects of the PSFS will inform about pain and how it affects function. The PSFS is reliable and valid with respect to what it supposed to measure - Paul Straford and his team have done a good job in building this measure.

Hello Morten. Another variable is the influence of the COMT gene, defects in which run the gamut from causing a person to experience no sense of pain (which can lead to fatal consequences) to causing someone else to feel abnormally intense pain from the slightest touch (which can possible lead to depressive episodes) . I am trying to find a lnik between this latter defect (genetically low pain threshhold) and chronic akathisia, ADD / ADHD and a few other emotional disorders. Shouldn't any scoring of perceived pain take into consideration a subject's innate ability to withstand pain by looking at this gene so that your comparisons start with the same genetic baseline?

Hi Morten. I just read through other answers to your question and I would like to add one more comment. When people suffer chronic pain in their daily lives, many emotions can intensify or mitigate it. Any dopamine boosting activity can, as I'm sure you know, alleviate pain to some degree. The mere act of having someone giving them a test to score their pain could generate a huge dopamine surge that might have a temporary placebo effect. So any test or scoring that is conducted away from that person's usual setting by someone they perceive to be helping them is not going to reflect that person's usual state. In such a situation, if the person is feeling better but wants to provide answers reflecting their usual state, their answers will be based on their memory of their pain rather than how they feel right then. This exaggerating may make them seem to be lying. When answers seem contradictory, as suggested by other responders to your question, I think it is because of their poor memory of how the pain feels at "regular" times. Intense pain interferes with memory formation. Some people also dissociate during moments of intense pain. I think any type of subjective scoring is going to have these types of built-in problems in addition to the issues cited by the other responders. Are there questionnaires that are given to subjects to take home and complete over a period of time while they are doing their regular routines?

Hi Julie,

Thanks for adding a bit of genetics to the discussion. The role of genetics in nociception and pain is not new and by now means brought to an end. I assume there is recent evidence that I´m unaware of regarding the role of paroxysmal pain sensations and COMT as you describe.

Is it your belief that we can account for these genetic differences in humans (clinically) at present? If to - to what degree can or should it be used in your opinion?

Cheers

Morten

Sorry Morten, but I have to respond. In your last reply you say you consider disability a major part of chronic pain. You have to be very carefull what definitions you use. Disability or limitation of daily activity can be part of the whole problem a chronic pain patient is dealing with. However it is NOT part of chronic pain. They are two very different aspects that can even be contradictory in a patient: there are patients with much pain that are hardly limited in daily activity and vice versa. There are study's that show that other {psychosocial} factors may determine this relation. So I shouldn't consider disability PART OF chronic pain. For example I refer to a very recent {yesterday} dissertation of dr. Haitze de Vries, Working with pain. In this dissertation he compared people who still work despite the pain with patients who couldn't work because of the pain.

So as you already suggested, if you want to know something on limitation i daily activity you might need a Quebec disability scale, or a Roland morris scale. But you have to realize these are, like the VAS subjective scales. Therefore it would be wise to also have some objective measures of physical functions. Beware here: any physical capacity test is also affected by the subjects believes of how he can perform. It is possible to have any patient to have a significant increase or decrease of a test within 5 min's the moment you inform him on his functional possibilities {or limitations}.

There is an excellent neurodiagnostic test availabvle which can exactly this - Neuralscan. I helped develop it in the late 1990s but have no interest in the company. I have been using it to direct the level of my transforaminal injections in the back (in disc disease), to diagnose facet mediated pain (when the test is negative or near negative) and to diagnose neuropathy which we treat at my clinic (www.nvpainrelieflv.com).

@ Robert. How does relate to the question?

Pain is a subjective experience, while nociception is activation of the nociceptive pathways. The two are not the same. See IASP definition of pain, and note the last sentence of the notes associated with the definition.

Psychosocial aspects of pain are integral to the experience of pain. Disability (activity limitations) may, or may not, be associated with having pain, but isn't necessarily present with all pain - the correlation isn't 1:1.

So... in answer to your first question, is there a way to assess pain and not nociception, yes there is - primarily through self report. Which is not necessarily "accurate" because there is no gold standard through which we can establish how pain feels.

To assess nociception probably involves measuring activation of the nociceptive pathways, or, as Gwyn Lewis (AUT) shows,using quantitative sensory testing.

To assess pain itself - probably best to refer to the work of Turk and Melzack and others, who have really explored this in depth.

Dear Bronnie Thompson,

thank you for your answer! I do not disagree to any of your points, however, I wish to challange them to increase my own understanding:

1. How does social aspects integrate into the pain experience? My interest here is first of all if it is modifiable and measurable.

2. QST is a fine tool but nevertheless it depends on the interaction between stimulus and patient response. We do not know which one test the most? If we test the nociceptive component the most how can we explain the wide range of responses? If personal responses are major contributors how can we then know normative values and define abnormal responses?

The German group on this topic show much too high variability in healthy voluntaires but a fairly narrow variability in patients. However, this gives us no clue about the influence of psychosocial-aspects?

3. I truely appreciate the work of Turk and Melzack (as well as others) on assessment of pain. And I believe we still have much to learn here.

One big issue in most patient self-reported measures is the inability for the clinician to interpret them with clinical significance. Take VAS for example it´s a simple Likert Scale and could at best never contribute with anything else than the mere intensity of pain or suffering. But does that really tell us anything about the complex causes behind pain?

It may be suggested that the simpler the tool the better because pain is so complex. But clinically this does not make sense. I don´t think that I know my patient any better after they have scored their VAS. Not even in combination with other measures do I get to understand what my patient is going through. This, of course, is my personal belief that it matters how well I understand my patient. But is it less right than the assumption that more intense (chronic) pain is worse than less intense (chronic) pain? Or is this only valid for acute pain?

An other way to assess patients experience is via communication. But do we have the skills to do so? Drawing upon the ideas of Varela and Thacker I would argue that we need to increase our skillset. They suggest different ways into "third-person-neuroscience" but Varela has a point when he studies Buddhist monks. They have years and years of practice in explaining and understanding 'experiences' that only exist in a first-person domain. Thacker/Moseley (2012) as well as Varela and colleagues suggest integrating first-person data into third-person data by studying pain experience with modern neuroscience.

So far, this is where the trail ends. Where does that leave the patients for the next ten years?

Comments are highly appreciated.

My take on the social aspects of the pain experience is that within a social context, humans are able to, and willing to, experience nociceptive inputs that in other contexts would be resisted. e.g. Body suspensions, tattoo (particularly Maori and Pacific Island tattoo with traditional instruments), and our practices around pain relief in childbirth. While the inputs might be the same, the experience of pain with all the emotional/cognitive elements is incredibly malleable. We can't tease these aspects apart from one another, and the social context is part of it. Another example of the social influence is within the family where, from childhood, we are all strongly influenced with respect to how we interpret nociceptive inputs.

With respect to interpreting VAS and causality in pain, I don't think this is possible at this time. Because pain is subjective we can't interpret a response as anything other than a behaviour influenced by all three aspects of the biopsychosocial model. Pain assessments need to be multidimensional, and no, we can't at this stage totally understand what our patient is experiencing, no more than we can know whether the taste we experience when we eat chocolate is the same taste experience as another person eating the same chocolate. Until we unravel consciousness, I don't think this will be achievable. But we can use our listening skills, and our empathy, and acknowledge that when a person says it hurts, it does hurt. And in using CBT, ACT or other psychological strategies, along with activities and exercise, we can help the person reinterpret their experience and cope more effectively within the context of their lives.

While I agree with Bronnie in almost every aspect of her latest comment, I do so with qualifications. While it is true that we can not really measure the personal experience of pain as there is no objective, external reference standard. However, there is some objectivity here. If I hit my thumb with a hammer, it will hurt. The same action will hurt Bronnie and anyone else with an intact nervous system. It will hurt a lot. If local anaesthetic is injected around the the nerves supplying the thumb, the pain will stop - quickly, predictably and for a length of time consistent with the known properties of the injected drug. My point here is that many pains ARE well understood, can be measured well enough for most purposes and are treatable. You certainly do not need CBT or ACT to manage such pains. 90% of the pains I deal with in everyday clinical life do not need CBT or other psycho-therapeutic intervention. I don't mean to pick on surgeons especially, but as a small group in medical care practice, they seem to have the largest proportion of individuals who have poor bedside skills and some can be quite abusive with patients who will have a very negative experience. This does not stop them from getting excellent clinical results in a significant proportion of cases. My point here is that just treating the medical condition does actually work - often. Of course, empathy and excellent patient management skills with specific CBT knowledge and skills, greatly enhances results and significantly improves the patient's experience, but it is a mistake to conclude that pain is some sort of mystery wrapped up in an enigma which may be called a biopsychosocial phenomenon. Absolutely there are biological, psychological and social aspects to the pain experience - to us, at the conceptual level when we consider the enormous variations that are possible in the experience and how people respond to tissue damage and distress generally. Sometimes it is hard to separate out the nociception from the emotional aspects and social interactions that accompany the complaint and the experience. But equally it is often easy to see the nociceptive component and treat it accordingly.

I can't completely agree with you Mark, but of course you'd figure that!

I don't think CBT or ACT are required in every case, but I DO think that psychological and social factors are present in all experiences of pain, whether acute or chronic. I also think that whether recognised and manipulated overtly or not, every clinical encounter in which pain is influenced involves psychological and social factors, along with the biological.

I think the original question was "How can we assess pain and not nociception?" not "does managing pain require all three aspects", and I think the answer is - we can't.

Your point that pains "...can be measured well enough for most purposes and are treatable" is well made, but doesn't answer the question that needs to precede it: why did the person come in for treatment? Why did this person experience the pain in that way when other people with the same nociceptive input experience it differently?

A really good example of this is in myocardial infarct - some people experience the sensation as simply epigastric discomfort and take an antacid, and it's only later they recognise it as an MI - usually during postmortem!

Others will experience discomfort, seek health care, get treated, and then each time they experience epigastric discomfort, seek health care.

Learning forms a good part of our experience of pain - personal learning, learning from observing others, and learning from what we are told. This is why I suggest it's important to integrate the psychosocial management with the biomedical.

Each experience of pain, whether successfully resolved or not, provides a learning opportunity for the individual. How well we as clinicians (and society) manage this, particularly with respect to helping people understand and reduce their distress, increase their self efficacy, will influence how well they cope with the next episode of pain. People who are less distressed require less analgesia post-operatively, which reduces the risk of complications from analgesic use, and enhances recovery.

What I don't understand is why there is such anxiety and reluctance amongst particularly biomedical/biophysical clinicians to the notion of an inclusive biopsychosocial model. Does it need to be "either-or"? Why not be "and-and"?

@Bronnie

We are not in disagreement at all I think. I have never disputed, nor am I reluctant to integrate the psychosocial with the biological aspects of pain when discussing the theoretical aspects of pain. It is just that you and I probably see, in the main, the opposite ends of the spectrum While most of my patients have a "bio" component that predominates in terms of treatment needs and the psychosocial is along for the ride, I suspect you see the other end where the "bio" is so buried in the psychosocial dimension that the bio seems incapable of being teased out from the complexity of the florid chronic pain patient. I do see these patients too but less frequently. Even the most obvious 'bio' case - like a fracture or a wound carries with it the learned experiences and responses to past instances of pain woven into a behaviour pattern. This is why one patient with bones sticking out of the leg will grit his teeth and make humorous comments to the ambulance officers about how he will have to put off the Tongariro traverse until next month, while another will scream and cry, wail and moan as if he will be crippled and in pain forever. The injury is the same but the responses are different. The treatment - at least initially is not that different though - provide relief from nociceptive input, reduce the fracture, stabilize it and let nature do the physical healing. However, the different responses are cues to how pain relief and rehab should proceed. They are cues only however. I have seen the former patient become disabled and chronically painful because of poor management and interaction with the health care system despite the initial rather positive response type. Conversely I have seen the latter case calm down rapidly once pain is under control and proceed through rehab without a hitch despite the initial 'yellow flag' type of behavour initially.

My point here is that the clinician must be responsive to what is needed when it is needed, and not doctrinaire in either direction about what approach or mixtures of approach are needed, for it can and does change from patient to patient, and for any given patient throughout the process of acute presentation to rehabilitation.

Again, I reiterate, I have no quibble with your statement "..that psychological and social factors are present in all experiences of pain." Absolutely correct - we are not insects but perceptual / cognitive / emotional entities, enormously complex and individually unique. Nociception is a primitive sensory level data input and pain is the experience of, and the behaviour in response to, that sensory input. I think pain arising completely de novo is rather rare is it not?

Yes, i think it is quite rare, although migraine springs to mind as a possible candidate for a pain that emerges without direct nociception, or so I'm lead to believe. My points were really that in my teaching, and clinical work, as well as what I've been discovering within primary care, it seems vital to integrate the biopsychosocial - and by and large, clinicians do. We explain to a person what is going on, we treat within a social context, we reassure, we treat with pharmacology or sutures or whatever. (well, I don't because I don't directly influence pain or nociception). The biopsychosocial model doesn't mean engaging in CBT with each prescription! It does mean careful choice of words, attending to context and being aware of the unintended consequences of treatment choices eg reinforcing distress by providing immediate pain relief with pethidine for a chronic back pain each time the person has a flare-up!

no quibble there Bronnie. My thoughts precisely!

@ Jan Paul

Interesting comment - I might have to have a bit more from you to understand it fully. Do you or did the dissertation suggest that there are people in chronic pain do not have any disability?

I agree that professionals need to differentiate the two for semantic and scientific purposes. But does it hold to be true in the clinic?

Thanks.

Morten

Hi Morten,

My reply was already some comments ago and I have been reading the discussion of Bronnie and Mark with interest and pleasure. Haitze de Vries (university of Groningen, Netherlands) has looked at people with pain who still work and those who don't work. What he found is that from the perspective of disability / limitations there are no significant differences between both groups. Both have limitations, but the working group seems to deal with the problems in a more adequate way allowing them to work. One important clinical consequence is that graded activity programmes with the purpose to increase funcional capacity might not be so usefull since there obviously already is enough functional capacity. It seems that the subjective perception of what is possible is more important.

On the other you have to be aware of the following: We see a lot of chronic patients that still work, with all kinds of physical compensation strategies. In that way they can work, but will not physically recover. In other words, by working with compensations (not money but abberrant muscle strategies) they prolong their physical problems. Only if they temporarily diminish their workstrain for some time they can enable their body to restore proper control strategies (at least that is our perspective, which is quite succesfull in dealing with chronic pain)

My research also found many people who cope well despite their pain. The things that distinguish those people from the ones I've seen in clinical practice are that they apply their coping strategies flexibly, and that they have important activities they want to, or need to do. They seem to have been able to accept their chronic pain and "get on with it" using whatever strategies they have to hand, but only insofar as these strategies help them do what they want to do.

Thanks for the helpful answers. Is it your experience that this is or should be the consensus in the field of RTW-strategies for people in persistent pain? To focus on beliefs/subjective goals/acceptance rather than (or in addition to) activity-based approaches?

Yes, my specialty in clinical work is return to work, and it so often is about self efficacy for coping with pain at work rather than physical fitness. Fitness or exercises do provide a good vehicle for people to learn to cope with their pain, because they have a clinician monitoring them, it's a controlled environment, they learn to progress their exposure to movements and sensations they may otherwise avoid. In my experience, people who only have gym programmes during recovery, however, might be very fit but not be able to apply this in functional situations. I think this is where occupational therapy, with the focus of applying skills in vivo, is very strong, linking what has been learned in a clinic (psychology) or gym (physiotherapy) to the real world. Of course there needs to be a lt more research to understand the various components to a successful RTW programme, but this is my experience.

@Bronnie and Morten,

Although I agree that for many patients their beliefs limit them in going back to work ('i will get worse or damage my back'), we have to be carefull there is a significant group where going back to work without proper physical function may indeed prolong their complaints. In this context I studied the relationship between fear (of motion, using the tampa) and physical dysfunction. The result was that there is no relationship between fear and dysfunction. In other words: we have to be carefull that besides the regular groups, there are both patients who have to much fear in respect to their physical problem but also patients who have TO LITTLE fear with respect to their problems. We assume the latter are the specific patients that continuously overburden themselves. They are easy to get back to work but will in the long run get worse because they do not allow their body to recover.

If we consider the workplace as the context for recovery, then titrating the type of work and closely monitoring progress (and liaising with the workplace) can mitigate this tendency for some people to overdo, and others to underdo. I think we've tended to think of treatment occurring in the confines of a clinic and hoping people will return to work just because they've "got better", but again, it's not "either-or", it's "and-and" - good management is a system effort from all providers working together to promote recovery and return to function.

Your thoughts on RTW are very interesting. Do you have a theory, regime, check-list or similar, which have been published? I´d like to read more about it.

Dear Bronnie, Theoretically I fully agree with you. Regrettably daily practice in the Netherlands shows that reintegration specialists too often (with exceptions of course) are penny wise and pound foolish, pressing chronic patients to return to work as soon as possible, neglecting both the behavioural aspects of patients as well as their physical status. 'if you have non-specific back pain there is actually nothing wrong with your body, so just pick up the work and you will be fine.....' .

1. VAS

2. Brieff Pain Inventory and other test adapted to pathology

3. Euro Quol

And with Clinic exploration!

greetings all,

this is a very interesting question, with great responses. I am very supportive of Bronnie's posts. The one thing that i would like to posit is that situational circumstances/current social capital also can have a big impact upon clinical picture. For example, when i am exhausted after a huge day at work, combined with less than harmonious relationships at home, my coping resources are diminished, and i may 'feel' more pain or distress.

it is a complex subject that is hard to tease out, but so important for clients/patients who live with ongoing and persistent pain.

Hello:

 First of all I apologize, I speak Spanish and my English is very bad so I am using a translator.

The pain has several components. Begins "normally" with nociceptor activation. However, when any part of the nerve is stimulated or curtailed, this segment electrical discharge starts later become pain. Thus, the pain is so difficult to treat. You can shoot from anywhere in the nervous system.

In addition, we have been genetically conditioned to feel more or less intensity. This is not even debatable. Is proven.

However, all this is under the command of the brain, the mind, the psyche or whatever you call ... When the pain is a reason you validate, stops hurting. An individual can endure unimaginable pain if you think that this will reach Paradise, for example. Or, if you think this will help their children. Anyway, I could give all kinds of examples. Also, it seems innocuous stimulus can arouse EVA joins 10 if unresolved memories. That is, when the pain is not a reason, the whole system is activated, is exacerbated, in search of an answer to the problem. Is activated so that the question can be inherited to the next generations until someone figures out why or give a value that justifies it.

Our purpose in the universe is looking for information to pass to the next generation. Pain is the best teacher and more malevolent. The disposable nature made us and if we suffer, we suffer to learn something that makes the species getting better.

I'm not sure we're going in the right direction but that's another topic.

I send the espereranza start dialogue.

Eddy Salvador M

Physician Anesthesiologist

Master of Pain and Palliative Care

Master of Clinical Epidemiology

Dear Sir,

A good initial account on this subject can be found on the book "The management of pain' edited by John Bonica, Lea and Febiger, Philadelphia, 1990 (2nd ed). The book covers practically all aspects related to pain, including its measurements. The complexity of pain expression is summarized on the four components of Loeser´s concept of pain on page 562 (vol. I), as described by Bonica and Loeser.

Please look at the attached Word file. I have made comments and included a brief case study for your consideration. I think that the differentiation between nociceptive and central nervous system pain / neuropathic pain is important, but not impossible.