Meaningful movement, Pain ‘memories’ and Recalibration!
The idea of relevant and meaningful movements is important to us here at Cor-Kinetic so I thought I would jot down a few thoughts on some recent stuff I have read, digested and wanted to organise my thoughts on!
It is often specific movements that can be problematic for people, movements that we could deem as relevant or meaningful to the human being standing right there in front of you.This could be bending over at a specific angle for someone with back pain or be associated with specific movements such as serving in tennis or hitting a golf ball.
These movements maybe scrutinized more closely by someone’s central nervous system than other movements deemed less threatening and may produce disproportionate levels of pain and fear as a response.
These movements may shape someone’s sense of disability and quality of life such as not being able to play sport or pick up their kids or even tie their shoes.
The current perception towards performing certain movements maybe influenced not by the actual current state of someone's anatomy but the perceived state of their anatomy or the associated learning that has occurred based on previous painful experiences. This associated learning process has been dubbed ‘pain memories’ and we will discuss the science and theory behind them later in the piece. These altered perceptions may influence the pain state far beyond normal healing times and involve increased sensitivity and movement behaviors associated with pain. The psychological factors can have a very real effect in terms of the motor behavior, biomechanics and physiology of an affected area.
In part two of this series we will look at the mechanical and physiological changes the motor system may exert based on psychological factors such as fear avoidance and protection, both psychological and physiological/mechanical factors may concurrently influence someone’s current state.
These could be:
- Adverse Neurodynamics. Abnormal tension and compressions including tourniquet effect
- Decreased blood flow (heamodynamics) and ischemia
- Decreased/increased afferent information – Mechanical and neurological!
- Deconditioned tissue (possible atrophy and fatty infiltration) and work capacity
The idea of movement recalibration is to help calibrate the perceived state of the tissue and subsequent movement behaviors, and the actual reality of the reduced threat that a movement might now pose to the organism after significant time has elapsed. A negative perception can result in negative movement and sensation (discomfort right up to pain) responses. We will discuss both cognitive input and movement input later to help the recalibration process.
Recalibration is more than thinking just about the muscles, tendons, nerves, bones etc, instead it is incorporating the human aspect into the anatomy as well.
Recalibration is thinking about how the human being perceives and responds to the idea of movement in general, specific movements or movement in specific parts of their body e.g. the lower back.
This could be at the extreme end of the spectrum in the case of ongoing debilitating pain or form part of an underlying niggle that never seems to be fully resolved. The association of pain and movement may happen after many injuries and contribute to lots of ongoing discomfort and pain states.
Lets put this into a context:
“John (45) has had a long-term shoulder problem (3 years) when he goes into shoulder flexion above 90° that has previously been diagnosed as an ‘sub acromial impingement’. It becomes significantly worse when he moves very quickly or picks something up heavier than usual. He has seen many therapists and previously had scans that showed some minor structural change. He has had various manual therapies performed including massage and also ultrasound. He has also previously been given some theraband exercises to do.
It has restricted him going to the gym, playing sport or doing DIY around the house. It significantly affects what he feels he is capable of doing and has hampered his activity levels and his love of tennis that was his main physical activity. It originally came on after a tennis tournament. After an initial period of rest it has got marginally better but has never really gone away and can be felt every time the arm goes above 90° and anything heavy, fast or for prolonged time can flare it up sometimes for a couple of days. He knows every time he performs these actions it is going to affect him. He has given up trying to go back to playing tennis as it consistently sets him back.
John feels he has put on weight and suffers from less energy since he cannot play tennis. The tennis club was also a source of much of Johns social life as well, something he feels has been affected”
Not only do we see the activity is deemed a problem it has also caused significant impact on other parts of John’s life. Getting his arm overhead and being able to perform the activity holds much more meaning than just the physical action itself, it impacts on many areas of his life.
What that pain could mean to John’s life may alter the way the CNS processes information coming from his shoulder. That John believes (what he has been previously told) tissue is being repeatedly compressed and continually damaged may also influence his responses.
Are there lots of people out there like John? Have you met someone like him? They can have significant long-term problems with their shoulders or knee’s or backs or whatever’s. They can carry on but with seemingly ‘permanent’ problems.
Could the problems be in the beliefs and conditioned responses rather than or as well as the tissue itself? Can our perceptions also manifest into the biomechanical and physiological realms?
John knows he is going to get pain as soon as he is asked to raise his arm. You can see it in his face. He clenches his jaw and holds his breath. His shoulder girdle elevates and you can see his traps tighten and elevate and scapulae slightly protract. He goes into some spinal flexion and there is no downward or posterior rotation movement from the scapulae. The rigidity in response to the movement even before he gets to 90° is obvious.
John is completely unaware of any of these physical responses. To him they are just part of the action of raising his arm. They are subconscious and conditioned. At one point they were probably adaptive (helpful) to avoid stressing the injured and painful tissue but possibly now we could label them maladaptive (unhelpful) and could be contributing to the ongoing problem.
When we get John into the relevant position of an overhead tennis shot (the most problematic) very little movement comes from the rest of the kinetic chain and the range of movement at the shoulder decreases. It is markedly decreased with a weight or the introduction of increased speed.
Simply asking John to relax before he moves, keep his shoulder down and in some spinal extension has a profound effect. Range of movement increases and it feels different somehow, a little bit better.
“See John, when you relax it feels a bit better”
John - “Oh yeah”
“You can get a bit further and not so painful, we can work on that!”
We could also see how simply altering John’s perception of the movement actually alters the mechanics of the movement.
We could have a look at John’s ability to depress his shoulder girdle, move into some spinal extension and also his trunks ability to extend. We could look at how all these thing interact in the relevant movement of hitting a tennis serve or overhead shot. This would be meaningful and relevant.
Pain memories and associative learning
Associative learning in its most simple form is between two events. In the context of this post that would be pain and movement.
The classic example of associative learning is that of Pavlov’s dogs, which I will try my best to make some sense of in a simple way!
Pavlov found that his dog’s salivated when they got food, a completely normal biological response. The food being what he termed an unconditioned stimulus and the salivating an unconditional response.
For humans pain is an unconditioned stimulus that brings about an unconditioned response of fear and protection.
Pavlov found that when he coupled the unconditioned stimulus, food, with a neutral stimulus, ringing a bell, the dogs would then associate the two events and he could get the dogs to salivate with just the ringing of the bell. The bell became a conditioned stimulus with a conditioned response of salivating.
If John raises his arm repeatedly, a previously neutral stimulus, and gets pain then the neutral stimulus may get associated with the unconditioned stimulus of pain. Now raising the arm becomes a conditioned stimulus, much like the bell to the dogs, with fear and protective behavior becoming a conditioned response. These behaviors could involve fear avoidance, hyper vigilance and motor system responses (protection) such as reduced range of movement and general rigidity in associated areas.
Pain as an association/prediciton has been previously discussed in this blog ‘Pain and prediction’ *Click Here*
In the “The brain that changes itself” author Norman Doidge discusses Indian neuroscientist Ramachandran’s view of the association of pain and movement for some of his patients.
“Ramachandran came to believe that in these chronic pain patients the pain command got wired into the pain system, so that even though the limb had healed, when the brain sent out a motor command to move the arm, it still triggered pain”
‘The brain that changes itself’ Penguin, 2007, p193
An interesting new article from Moseley & Vlaeyen (who has looked extensively at the fear avoidance model) *Click Here* discusses pain starting to become the conditioned response rather than a stimulus for other responses.
In Moseley & Vlaeyen hypothesis, nociception (noxious or harmful stimulus) is no longer needed as the stimulus for pain. The associated proprioceptive input that accompanied the nociception actually becomes the stimulus and now could evoke an associated response of pain without the need for any of the original noxious stimulus. John’s now conditioned stimulus of raising his arm causes a conditioned response of pain. The movement and pain become linked with no nociceptive input actually coming from the tissue.
We encode meaningful events into neural patterns that have associated components such as proprioceptive, visual, auditory and pain. We may also link emotion and memory components; this process has been described as ‘acquisition’
These unique patterns of neural activity have been described as a neurotag or neurosignature. In the ‘Graded Motor Imagery Handbook’ (NOI group 2012) Moseley et al describe this as:
"A neurosignature (or we call it a neurotag, like a graffiti tag) is a pattern of activity in the neuromatrix. It is a physical linking of neurones at a particular time and it can lead to an output such as pain, movement or an emotion”
Moseley & Vlaeyen also describe the concept of 'imprecise coding' of neural patterns in their article. With imprecise coding of a neural pattern we may now see less specific and more generalized pattern recognition elicit a conditioned response of pain and associated protective behavior. In this way many different and varying movements could cause a response of pain that are only loosely associated with raising the arm or even the concept of raising the arm. Couple this with also imprecise and reduced proprioception and changes in cortical representations (used for our movement planning) and any movement of the arm in the general direction of overhead may become a potential minefield for John.
Kinesaphobia (fear of moving) is often associated with a specific movement such as flexing a back or movement onto an injured knee. Kinesaphobia has been shown to be significant after ACL injury *Click Here* *Click Here* as well as implicated in chronic back pain *Click Here*
Does this fear of movement over time start to transition into fear-avoidance? The fear avoidance model is relevant here as the theory may involve associative learning in the transition from acute pain to chronic pain with a lack of obvious pathology present. *Click Here*
Fear avoidance maybe a conditioned response to a specific action. If we look at the time scales of many problems coupled with continuing avoidant and protective behaviors the relationship with pathology may become weaker and the behaviors and beliefs stronger.
Zusman (2004) discussed the concept of pain memories/associations in “Associative memory for movement-evoked chronic back pain and its extinction with musculoskeletal physiotherapy” *Click Here* He describes neutral or innocuous cues prompting “avoidance, preparation, protection”
Zusman describes the convergence of the neutral and noxious stimulus on to the “same amygdala neurons” and the amygdala (brain area proposed to deal with threat and fear) “learning and remembering”.
This would result in an associative learning process.
“The present proposal is that, acutely, innocuous proprioceptive information created by static and dynamic movement (the ‘neutral’ input) becomes ‘associated’ with that for nociception (inflammatory pain) following their convergence at appropriate neurones in the amygdala”
We may get contamination of normal or neutral proprioceptive afferent input with strongly associated pain responses. We learn to output pain as a reaction to the normally non-threatening input.
This is stored as a neural pattern or ‘pain memory’. We have both top down and bottom up influences that reinforce these memories and behaviors and can lead to long-term problems with specific, or with imprecise coding, possibly less specific movements.
Nijs et al in “Exercise therapy for chronic musculoskeletal pain: Innovation by altering pain memories” *Click Here* discuss the fact that movements that are painful in an acute phase are often perfectly safe in a chronic stage.
“The problem is that the brain has acquired a long-term pain memory, associating such movements with danger/threat. Even preparing for such ‘dangerous’ movements is enough for the brain to activate its fear-memory centre and hence to produce pain (without nociception), and employ an altered (protective) motor control strategy”
Recalibrating the perceived level of threat/protection to the current state of the tissue here should be an aim. It is not the tissue and signaling from the tissue that has become a problem but instead the movement itself and the associated responses it triggers as proposed by Mosely and Vlayaen.
It has been hypothesized that we use our previous experiences stored as memories (neural patterns), such as seen with Bayesian probability, and our future actions are guided by our knowledge of previous situations. This would be previously encoded neural patterns evoked by similar afferent sensory information or internal desires used to form a predictive model of immediate upcoming events, the net result maybe repetitive conditioned fear, protective responses and even pain.
Both Nijs and Zusman discuss changing the perception or memory of the particular movement or even movement in general. This would be the ‘recalibration’ of the protective response towards what should now be perceived as a neutral stimulus, raising the arm in John’s case, with a normal pain free response.
Zusman describes this as ‘extinction’ of the previous memory by using ‘exposure without danger’ to get to a situation where by the input does not cause a pain output. This is designed to disassociate a normal and innocuous stimulus and the response of pain. This has been called by many names including a ‘graded exposure’ & ‘desensitization’, essentially they all work to reduce an output through measured input.
By providing different initial responses to a movement, possibly through reducing fear behaviors via relaxation, and creating more variability in movement input we can hopefully build new ‘memories’ or encoded patterns with different associated responses that become the dominant neural patterns.
For associative learning to occur we must have a difference in the actual and expected outcomes. If we have the same stimulus and response relationship only reinforcement will occur. Just recreating a movement will probably give us exactly the same outcome. We must change the attitude towards the movement and/or alter the movement itself in some way.
Creating change in the actual outcome has been proposed to happen in two main ways:
- Cognition targeted
- Movement targeted
An approach involving both the cognition and movement focused approaches maybe more likely to obtain the most favorable outcome *Click Here*
Both approaches are encompassed in our 5 R’s of rehab approach *Click Here*
- Red Flags
- Reconceptualise – Cognition focused
- Recalibrate – Movement focused
- Robust – Movement focused
Cognitive based input is aimed at helping reconceptualise how someone views pain through education about the neuroscience of pain.
This could be decoupling the concept of hurt always equaling harm and a simple understanding of the central and peripheral changes that occur with ongoing pain.
Cognition targeted input could also be used to address perceptions of the anticipated danger of an exercise and the possible pain (and hence damage in their eyes) that the activity may cause. Challenging the nature of the fears and the rationales behind them may lead to a change in perception.
Simply asking John “Do you feel this is threatening for your shoulder?” Asking why and then working through the reasons given. This can be followed up after the exercise or movement, hopefully the cognition-targeted input helps recalibrate the expected level of threat with what is actually experienced.
The use of personal goal setting is also proposed by Nijs. These goals could be returning to work or sport and can then be used to motivate and increase expectation of outcome.
A Movement targeted approach could be two fold, involving the introduction of new and novel forms of movement that are non-threatening and give a varied exposure and also variations of feared movements, a more specific form aimed at movements involved with fear responses such as raising the arm or bending over.
In the beginning not triggering a large pain response maybe important, especially for gaining trust, perhaps working to discomfort rather than pain. This may fall in line with the ‘graded exposure’ or ‘exposure without fear’ concepts.
Nijs et al suggests exercise also being time contingent rather than pain contingent and this concept being introduced during cognition-targeted discussions. By understanding their pain better hopefully someone can then fear it less. This process maybe important for pushing through previous barriers and building a greater ‘zone of safety’ or capacity for activity.
Changing fear behavior (which may now be the conditioned stimulus) such as simple relaxation before movement may also provide a change in associated pain and movement behavior and provide a new decreased pain or even pain free experience.
Altering the sensory input may also change the output. If we put this into context with John and raising his arm this could be proprioceptive, simply changing the rotation of his arm will stimulate different mechanoreceptors. Altering spinal extension may cause an effect, as may scapulae or cervical position or the alteration of movement in any associated segment. This would be similar to a symptom modification procedure as proposed by Lewis but based as much on the rationale of altering input and central processing as well as the physical affect on the tissue *Click Here*
It has also been proposed that changes in visual and vestibular information and fun and distraction may also create changes in the input-output relationship.
For John raising the arm above shoulder height at different angles may also create a change in input and therefore output within the context of a closely related version of the feared movement.
Working on a variety of targeted movements at the joint aimed at stimulating perhaps previously dormant movements, an example being depression of the humeral head with a variety of three dimensional humeral positions, could stimulate the motor and proprioceptive systems in new and novel ways that alter input and create plastic changes in brain structure for future use.
Finally increasing the robustness for tolerating time (endurance), speeds, loads and a variety of positions must be addressed. All of these inputs may influence output based on perception of capabilities. Addressing the specific functionality of the game of tennis and associated demands would also be highly relevant.
All this would all be aimed at returning John to doing what he loves most and has so much meaning for him, the game of tennis.
Part 2 of this article will look at the possible physiological and mechanical affects of psychological issues.
If you are interested in learning a bit more about this approach then check out our courses *Click Here*
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