I’m struck at how often clinicians focus on pain intensity when how much pain intrudes on life matters more. I wonder whether new therapists might not have read some of the old studies looking at the relationship between pain intensity and disability – because while there is a relationship there, it’s not nearly as strong as we might think.
Let’s define a couple of terms first: pain is, I think most of us can agree, “an unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage”. (click for full definition and notes)
Disability isn’t quite as clear-cut a term and it’s gone through a few permutations over time. Probably the way I define it fits more with “functional limitations” – but the diagram below from WHO describes their model of disability .
In other words, disability is the combined impact of all of these aspects of health on a person. Pain arises from some kind of health condition (yes, even pain where we’re not entirely sure of the “diagnosis” and where we can’t quite yet be definitive about what’s going on). In turn, pain influences body functions (and perhaps structure – certainly there’s a lot of evidence showing altered neural networks while someone is experiencing acute pain, and changes are also present in persistent pain conditions. See the refs below – but interpret cautiously, this is an emerging area of research).
All of the relationships above are bidirectional, meaning that there’s no linear path from one aspect to another – it’s complex.
What this means is that we shouldn’t be one bit surprised that the relationship between experiencing pain, the health condition, what a person wants to do, how much they participate, and their context is not at all straightforward. Yet so often I see research papers looking at altering one aspect of a disorder or disease, measuring pain as the primary outcome, and being a bit surprised that even though the pain might have reduced a little – the person isn’t “taking advantage of it.”
A good example of this is returning to golfing after knee arthroplasty. Prior to surgery many people have taken to golf carts so they can get around the course. After surgery, with less pain in most instances, you’d think people would go back to walking the course – it’s a great way to keep fit, it’s not as difficult to do as a bunch of gym-based knee exercises, and it makes for an enjoyable game. What actually happens? Jackson, Smith, Shah, Wisniewski and Dahm (2009) found that over half (57%) returned to golf within 6 months, with 81% playing golf as much or more often than before surgery. They reported less pain with 83% reporting no pain – 28% had walked the course before surgery, so what percent do you think would carry on walking now that their pain was less?
Only 14% walked the course after surgery.
No relationship between walking and age, sex, BMI, pain, receiving advice not to, bilateral or unilateral prosthesis, or current golfing handicap.
Even in acute musculoskeletal pain, where we know that to wait until all pain has gone will harm the person (think of your ankle sprain) it seems clinicians would rather address pain intensity than the impact of pain on what a person wants and needs to be able to do. Case in point: Adam Meakins recent back pain.
I’d love to hear clinicians dig just a little deeper – like “so if pain was less of a problem, what would you be doing?” Because we know that people seek treatment for back pain because of the effect on what the person wants to do – Ferreira, Machado, Latimer, Maher, Ferreira and Smeets (2010) showed this in a meta-analysis over a decade a go.
Is it either/or though?
Well by now readers of this blog should know that I don’t think anything is as simple as a dichotomous yes or no. Of course pain intensity matters – but what I often see, especially on social media, is an almost exclusive focus on pain intensity and “proper” form and “exercise” with little attention to what it is the person wants to do.
Because the unknown part of the Jackson et al (2009) study is why these people didn’t resume walking, even though they were in less pain, and were playing golf more.
I’m picking the reasons lie within those pesky contextual factors – who is around the person, their physical environment, community attitudes and beliefs, their fears and anxieties, what’s thought to be normal or expected – the bread and butter of occupational therapy, and coincidentally, the most complex part of health to research and understand. No wonder there are those who prefer the conceptually simple mechanistic, biomedical approach – these psychosocial (emphasis on the social) can’t be rote learned and spat out in an exam, they need conceptual understanding and unique, individualised solutions.
Barroso, J., Wakaizumi, K., Reis, A. M., Baliki, M., Schnitzer, T. J., Galhardo, V., & Apkarian, A. V. (2021, Mar). Reorganization of functional brain network architecture in chronic osteoarthritis pain. Human Brain Mapping, 42(4), 1206-1222. https://doi.org/10.1002/hbm.25287
Ferreira, M. L., Machado, G., Latimer, J., Maher, C., Ferreira, P. H., & Smeets, R. J. (2010). Factors defining care-seeking in low back pain–A meta-analysis of population based surveys. European Journal of Pain, 14(7), e1-e7. https://doi.org/http://dx.doi.org/10.1016/j.ejpain.2009.11.005
Geuter, S., Reynolds Losin, E. A., Roy, M., Atlas, L. Y., Schmidt, L., Krishnan, A., Koban, L., Wager, T. D., & Lindquist, M. A. (2020, Jun 1). Multiple Brain Networks Mediating Stimulus-Pain Relationships in Humans. Cerebral Cortex, 30(7), 4204-4219. https://doi.org/10.1093/cercor/bhaa048
Jackson, J. D., Smith, J., Shah, J. P., Wisniewski, S. J., & Dahm, D. L. (2009, Nov). Golf after total knee arthroplasty: do patients return to walking the course? American Journal of Sports Medicine, 37(11), 2201-2204. https://doi.org/10.1177/0363546509339009
Wager, T. D., Hu, B., Jepma, M., Krishnan, A., Schmidt, L., Roy, M., Atlas, L. Y., Goldstein, P., Yao, Z., Woo, C.-W., & Zheng, W. (2020). Pain-Evoked Reorganization in Functional Brain Networks. Cerebral Cortex, 30(5), 2804-2822. https://doi.org/10.1093/cercor/bhz276