What is the arthrokinetic reflex and what does it have to do with strength, mobility, flexibility and joint mobility drills? Here is a (very) quick explanation.
The arthrokinetic reflex defined

Arthro means joint. Kinetic means movement. Reflex means involuntary movement in response to a stimulus. Put them together and you have a term coined by researchers in the 1950s as a way to describe the idea that sensory input from joint movement can reflexively cause activation or inhibition of certain muscles.

This theory was proposed as way to explain the results of an experiment where scientists deactivated a cat’s brain but were still able to effect muscle tone changes in the legs by moving the knee. Similar results were found in a different study involving the muscles of the jaw. The researchers concluded that abnormal jaw positions resulted in mechanoreception that reflexively created abnormal (and dysfunctional) patterns of muscular activation.
The arthrokinetic reflex and strength

Dr. Eric Cobb, the creator of Z-Health, uses this term as a way to explain why joint mobility drills may be a quick and easy way to increase strength, flexibility or coordination. The idea is that moving a joint alters the mechanoreceptive information coming from the joint, which can reflexively alter the activation of the muscles attaching to the joint. For example, there is at least one study where hip mobilization led to immediate increases in hip abductor strength.

But is this the result of the arthrokinetic reflex or some other neural mechanism? I don’t know if there is any answer to this question, but personally I don’t care that much. Mechanoreceptive information might end up talking to many different areas of the spine and brain, all of which might have some sort of influence, reflexive or otherwise, on how the muscles around that area should be activated in the near future.

If the sensory information basically conveys the idea that movement in the joint is safe, we should expect the nervous system to loosen its governor on strength, speed and range of motion. If the information suggests that the movement in question involves danger, we should expect increased protective activity, such as stiffness, pain, weakness, and altered coordination.

For the present, we have only hints. Research like Dr. Ozcan’s will help us better understand the risks, benefits, and complexities of inflammatory processes. Meanwhile, it’s a mistake to oversimplify and to assume inflammation is always a bad thing, and trying to prevent or treat it with special foods and supplements is little more than a shot in the dark, a gamble based on speculation. Eat your vegetables and stay tuned!

There is a common belief amongst some people involved in pain and pain management that a person with chronic pain should be consistent in their presentation. That is, be consistent in various settings, and consistent across various measures. This assumes that if inconsistencies are present there must be something going on to cause suspicion about the validity of the person’s presentation.

Returning to yesterday’s post, I discussed the distinction between nociception (activation of receptors in the nervous system), pain (the experience produced by the brain once it has interpreted the nociceptive action), disability (the changes in functional performance attributed to the experience of pain), and impairment (tissue changes). These are not the same! Today’s post refers mostly to pain and disability.

Pain is, as I keep spouting, a personal, subjective experience – you and I can’t share our pain except through our behaviour. And even when we describe it, we can’t actually experience what it feels like to have each other’s pain. What this means is that our behaviours, or what we do, are what conveys our experience to others but only to a certain extent.

While our experience of pain remains individual, our behaviour is shaped by all the influences around us. And just to make things more complex, the meaning of our pain experience is shaped by what we learn and believe about pain from interactions between ourselves and all those influences that shape our behaviour. Complicated? Oh yes.

So if I grow up in a family that is generally stoic, where my complaints of pain are ignored and I see that others in my family don’t generally cry or stop doing things when they are hurt, it’s likely I’ll also be less demonstrative about my pain than another person in a family where this is not the norm.

We also learn to behave differently in different contexts. It’s common to say a few choice words when we hit our thumb with a hammer in the garage on a Saturday afternoon, but we usually wince and gasp quietly if we thump that same thumb in Church the next day!

What this means in terms of consistency is that people often do different things in different settings when they have pain – maybe when they drive from home to a clinic they’re a bit anxious about what the consultation might mean. They get out of the car and walk quite carefully into the clinic and sit down rather gingerly. They’re not sure whether they’re going to hear good news, or not. They go through the examination and consultation, and get told they’re going to try a new medication that might help. Oddly enough, as they walk back out to the car someone looking out the window might see them moving fluidly and getting into the car quite smoothly. Suspicious minds might start to wonder if they really had “that much pain”.

Turning to assessment of pain now, it’s been said that pain assessment should incorporate a number of different dimensions. At the very least, assessment needs to consider the location of pain, the intensity and quality of pain, and some sort of measure of the interference pain has with everyday activities. Some commentators consider pain assessment should also make a diagnosis of the type of pain disorder present (or the cause of the pain), while others also think that psychological aspects of pain need also to be included (such as pain catastrophising, measures of avoidance and measures of mood and anxiety). And of course, assessments of range of movement, strength and reflexes are also often part of a pain assessment.

Should these measures all present a “consistent” picture?

Where we hurt and what it feels like (the quality of pain) don’t directly correlate with the amount of interference a person experiences from their pain. If I’m a pianist I might be really bothered by tingling and burning fingers, while less bothered about the same pain qualities in my feet. If I’m really anxious about my future as a nurse, I might be really concerned about my low back pain. If I’ve developed some effective coping strategies for managing my overall body aching, I might not be particularly anxious or have low mood despite having quite intense pain.

Inconsistency between various aspects of a person’s presentation doesn’t mean they’re faking, or that their pain is not real. It does mean we need to generate some hypotheses about the relationship between the various factors that could be influencing the person’s behaviour. To decide, on the basis of our own experience (which is always limited!) that another person’s pain is not real just because we don’t understand why they are doing what they’re doing, is a judgement call we can’t make, in all honesty. More than that, it doesn’t help work out what to do next to move the person from being disabled (or getting a benefit they don’t “deserve”) to returning to function.

Gatchel, R., Kishino, N., & Minotti, D. (2010). The Three Major Components of Behavior Used for Assessing Pain: Problems Faced When There Is Discordance Among the Three Psychological Injury and Law, 3 (3), 212-219 DOI: 10.1007/s12207-010-9081-0

Self management can mean helping people to be “actively involved in their health care and to provide a variety of creative and individualized strategies to deal with their health problem in their daily life and ultimately to live as normally as possible despite their symptoms” (Zuffery & Schulz, 2009) – but the Devil is in the details!

What exactly does being “actively involved” mean? Can it mean accessing treatments like massage, injections, acupuncture “as needed”? Or does it mean exclusively managing pain without recourse to so-called “passive” treatments? And what are the implications of either of these two options (and yes, shades in between)?

Let’s take the most extreme option, that of having a chronic pain problem like fibromyalgia where there is no definitive treatment and no structural deficit that can be “fixed”, and learning to manage this problem without accessing any treatments. Self management, in this case, might mean:

knowing as much about the diagnosis and underlying neurobiology as possible;
being “health literate” and able to negotiate through health care systems;
knowing how to select the appropriate coping strategy or strategies to achieve a specific goal; and
maintaining a healthy and active lifestyle, with full participation in occupations, activities and roles within the family and community

Alternatively, at the other end of the spectrum, for someone with a recurrent structural change (say low back pain that responds to medial branch blocks), self management might look like:

knowing as much about the diagnosis and underlying neurobiology as possible;
recognizing the “early warning signs” indicating that either a flare-up is happening, or the medical procedure is starting to ‘wear off”;
being “health literate” and knowing how to access this help as needed;
knowing how to select the appropriate coping strategy or strategies to achieve a specific goal;
maintaining participation in occupations, activities and roles within the family and community, while living a healthy life

There’s not a lot of difference between the two – one doesn’t access treatment, the other does. However – and here’s my take on self management – there is a great deal of difference in terms of managing fluctuations in pain, and in the focus on symptoms.

One of the predictors of coping well with a chronic health problem is self efficacy. Self efficacy is confidence that you can manage a situation yourself. At least within North America, self efficacy is influenced by having an internal locus of control – this means recognizing that the efforts the person does make a difference, rather than expecting or hoping that someone or something outside of them self will be effective. (There are differences in cultural expectancies, hence localizing my description).

Typically, it seems that people who can make a difference to their own health through their own efforts, feel more confident to manage fluctuations in pain – which, it has to be said, occur with all chronically painful conditions. Those that are hoping for something to “take the pain away”, or who try to rid themselves of the pain through avoiding activities when they’re sore, or increasing their medication intake or access treatments to reduce their pain, seem to be less confident to weather these fluctuations, and can become distressed when their efforts don’t work, or their pain doesn’t settle, or they’re asked to do things even when they’re sore.

Where’s the evidence for this? Well, Blyth and colleagues carried out a very large study of non-treatment-seeking people in Australia who had chronic pain. Their findings showed that “use of active strategies was associated with lower levels of disability, less distress, less reliance on medication, and less use of formal health care” – although combinations of what we might call “passive” coping such as rest and heat/cold were often used with active coping strategies such as exercise, changing position and so on.

Now I’m not comfortable with classifying various strategies as passive=bad, active=good. I think it’s more complex than that because my take on coping and self management is that we don’t use strategies without some sort of goal in mind. That goal might be to reduce distress so the kids don’t see Mom crying; it might be to remain standing so Dad can watch the football; it could be to keep going so the housework gets done; or it might be to be productive at work. I think we need to be cautious about simplistic classifications unless we also take into account the end goal, or the “what is important to the person” aspect of the coping strategy.

I have a sneaking suspicion, though, that it’s not so much the skills used in the process of living everyday life that promotes self management and self efficacy – I think it may be an “attitude”. In other words, it’s not what you do, but the way that you do it (or the spirit that you do it in).

My rationale for this is the growing evidence that greater pain acceptance is associated with less distress and disability (see for example, Wright, Wren, Somers, et al; 2011). They looked at pain acceptance and hope and optimism in a group of obese patients with musculoskeletal pain. Using the Chronic Pain Acceptance Questionnaire which divides pain acceptance into pain willingness (or how willing a person is to experience increases in pain during the pursuit of something important), and activity engagement (or how involved in everyday living a person is). They found that “pain acceptance remained a significant predictor of psychological distress and pain disability” even after controlling for optimism, demographic, and medical variables.

This is important stuff – along with the strategies, which have always been the focus of pain management, these attitudinal changes seem to be important in self managing pain. Now: how do we influence this attitude?

One final question: do people who have greater pain acceptance also need health literacy skills to manage the tendency of our health systems to want to offer a fix or a cure to people with chronic health problems? Because while our views have mainly about the person with pain and what he or she does, I don’t think we’re nearly as aware of, nor focus on, the influence of social forces like family, healthcare system, community attitudes and so on.