Welcome to this fortnights musings over research and articles. If you would like more information on courses we offer at The Knowledge Exchange click HERE. If you are looking for further support or research papers that you can’t get your hands on leave your details HERE.
Fear-avoidance model of chronic musculoskeletal pain: 12 years on. Vlayen & Linton, Pain. 2012
I thought I would dig up this slightly older paper as Johan Vlaeyen was just in the Australia for Explain Pain 3. I was lucky enough to have an opportunity to sit down with the man himself and discuss my own research and some of the ideas that have been stewing in my mind. This paper has been hugely influential in my own practice and also our course content over the years. Why? Because it discusses an element of persistent pain that we may be able to influence as clinicians, but may often, without malicious intent, be influencing in a negative way. The paper can be found HERE.
The backbone of this paper is the fear avoidance of pain, which you can see in figure 1. It starts at the top (nociception/injury), where we may or may not have an injury, resulting in nociceptive danger messages being sent to the spinal cord and on and up to the thalamus/brain where a painful experience emerges. If you follow the cycle to the left you see the model suggests threatening illness information, holding negative affective valence, maintains pain catastrophising, leading to fear of pain, avoidance of activities that result in pain, and further avoidance of valued activity/increases in disability. Despite these attempts to avoid the activities that hurt the problem remains unsolved, and the person continues to experience pain, and thus, the cycle continues. The other side of the cycle suggests that if we can reduce fear, afford them the opportunity to confront movements/tasks they are afraid of then we have a more optimistic pathway to recovery.
The model suggests (and is empirically supported) that the maintenance of fear may be perpetuated by not only our experiences but also the messages that are provided by society, and health care practitioners (threatening illness information). E.g. being told you have an unstable spine may further increase threat to the individual, perpetuating fear avoidance and safety behaviours such as abdominal bracing. A paper that I enjoyed that discusses clinical language and its influence on behaviour can be found HERE by Michael Stewart and Stephen Loftus. A quote from the paper,
In musculoskeletal rehabilitation, we should remain eternally vigilant about how our words may be interpreted. Human beings consist of muscles, bones, and tissues, but the words we use in therapy can have a profound influence on how people make sense of their bodies and how they interpret what they are experiencing. A term such as degenerative discs may sound mild and straightforward to a clinician but catastrophic to a patient. - Michael Stewart
Despite the fear avoidance model now being supported empirically, the literature initially was predominantly psychopathology driven. Other work has been bridging this gap into the physical based therapy practices such as Peter O’Sullivan’s cognitive functional therapy (CFT) where the aim of the treatment is 1) to help a person make sense of their pain, 2) be exposed to movements/activities they are fearful of with control, and 3) lifestyle change. Point 2, affords a person with pain the opportunity to attempt movements they are fearful of safely but with removal of safety behaviours/maladaptive strategies. This learning experience is aimed to transition a person from the fear avoidance cycle on the left of figure 1 to the right hand side, via gaining credible evidence suggesting the threat is less than they perceived. Pain education and helping the individual toward a more optimistic internal narrative may also be helpful tools in minimising the risk of moving into or remaining in the fear avoidance cycle. Samantha Bunzli’s work that explores low back pain using the common sense model is important further reading - HERE.
What I find alluring about these models is that the shift in focus becomes transitioned from pain reduction goals to meaningful activities that the person has been avoiding, further reducing fear and increasing quality of life. There is no shortage of literature that suggests no matter what tricks we use, we tend to only have small to moderate effect sizes in providing analgesia, or ‘fixing’ pain (READ MORE HERE). This analgesia also tends to be transient in nature, which paradoxically could result in some clients left feeling more broken. This for me, always seemed burdensome to be tasked with fixing someone’s pain. Although, analgesia may be the overarching goal for some people, I am far more inclined to spend time shifting the narrative towards meaningful goals the individual may have. In saying this, and in line with the fear avoidance model, we often see reduction in pain as threat decreases, possibly in part to the confrontation of meaningful goals. Despite this, there may be times where this does not align with person-centred treatment.
Figure 2. aims to illustrate some of my thinking on what may be occurring with our traditional clinical interactions where providing analgesia may take forefront of the clinical interaction. Although some people are seeking help only for some respite, I would argue it may not be as common as we may believe. In many instances it may be what the pain means, the persons sense making of their experience, and the impending disability that may be looming. Rather than assuming analgesia is the reason they are seeking my help I routinely dig deeper to understand what their expectations are but also ask why that is the case. Rarely is it the case that this is built upon sound reasoning and what we have come to understand in contemporary evidence. These people are worried and fearful (they are seeking help after all, right?) and if I am going to be true to the reason I started practicing in the first place then I will help them explore other strategies that we know can minimise the risk of being adopted into the fear avoidance cycle.
These models provide a lot of food for thought for how we should practice, and how we apply these principals to a person worried about their pain. Our traditional pathoanatomical models of pain are not only insufficient but may be a catalyst in perpetuating the fear avoidance cycle. Telling someone their pain is because they are moving wrong, that they will wear out, that they have terrible posture, are simple and common narratives that have the ability to create ongoing disability. Check out Eyal Lederman’s work for an interesting discussion on the topic HERE. In my opinion, not only do these narratives need to change, but the interventions we decide on, on a case-by-case basis need to be considered more thoroughly, and we need to work on how to better educate while still validating someone’s experience.
2. Are there differences in lifting technique between those with and without low back pain? A systematic review. Nolan et al.
I enjoyed this systematic review that has just been published by a sleuth or great authors including Kieren O’Sullivan and Ben Smith. They set out to look at differences in lifting kinematics and electromyography (EMG) of people with and without low back pain (LBP). The abstract can be found HERE. Out of the nine studies that met inclusion criteria, eight found people with LBP to move differently. Of these they found that people with LBP to move more rigidly, slower, were more cautions, and adopted a more knee biased lifting strategy than their pain free counterparts.
Other interesting findings of the study: Abdominal muscles including obliques and latisimus dorsi are more active in people with LBP (n=3 studies). Possibly indicating that core stability exercises may not be helpful for the reasons commonly explained to clients and two studies reported significant reduction in spinal flexion in those with LBP.
It should be noted that these findings are only associations. The review goes onto discuss why these may be the case, hypothesising a few options, 1. to protect the spine from excessive loading, 2. it is now a pain behaviour, 3. or that it may be driven by the social belief that ‘safe lifting’ techniques are safer for the spine.
Interestingly, higher levels of fear and lower self-efficacy are associated with greater trunk abdominal contraction HERE and less ROM HERE. Studies where treatments have focused on treating these protective behaviours as maladaptive have shown promise with findings including decreased fear, pain, and disability. Further, it may suggest that our safe lifting interventions and teachings (that are primarily founded in in-vitro studies, with conflicting results when it comes to lumbar flexion - see Jack Callaghan, Stuart McGill, Chad Gooyers for more on these HERE, and HERE). Other research HERE and HERE and HERE has shown that advising people on adopting an unaccustomed lifting strategy may be tied to greater risk than allowing them the opportunity to find the most easy and effective strategy for them, at that point in time. This might seem controversial to suggest how you lift is unique and the conventional advice of lifting with your knees and not your back is not founded on strong evidence. However, it is becoming more widely translated into common knowledge. Even the Queensland Government Worksafe webpage is across this (Image above)!
Overall, this one ties in nicely with section one of this weeks blog doesn’t it? I’d like to finish off with a quote from the papers conclusion,
This systematic review found evidence that people with LBP move differently (slower, stiffer, with a deeper knee bend) to pain-free people during freestyle lifting tasks. This pattern is most pronounced amongst those with more severe LBP. Interestingly, such a lifting style mirrors how people, with and without LBP, are often told how to lift. The cross-sectional nature of the comparisons does not allow for causation to be determined. However, there may be value in exploring whether adopting a lifting style closer to that of pain-free people could help reduce LBP.
Thanks again for reading, If you're interested in finding out how to apply the research findings above into practice, check out our courses HERE and mentoring HERE… Or drop us a line HERE.