pain behavior

Modifying pain behaviour (2)


Two concepts that receive limited attention in the allied health literature are nomothetic and idiographic approaches. I’m discussing these concepts here because when we’re considering pain behaviour, I think we can focus much more on “generic” (nomothetic) concepts than we do idiographic ones – and yet we say we’re about the unique person in front of us.

Firstly, this site offers a good summary of the difference between nomothetic and idiographic – click

Essentially, nomothetic approaches focus on underlying generalities, perhaps traits, and are a solid part of the science of measurement in psychology. Given that much of our allied health measurement practice is based on psychological theories (such as using aggregated or grouped data to search for differences in means between two groups), it’s not surprising that we’ve tended to reach for a self-report measure when we want to understand what a person thinks and does when they’re sore. Think of the Oxford Knee Score, or the Oswestry Disability Index, for examples!

Here’s an item from the Oswestry Disability Index (Fairbank, Couper, Davies et al, 1980)

Section 5 – Sitting
I can sit in any chair as long as I like.
I can sit in my favorite chair as long as I like.
Pain prevents me from sitting for more than 1 hour.
Pain prevents me from sitting for more than ½ hour.
Pain prevents me from sitting for more than 10
minutes.
Pain prevents me from sitting at all.

When a person reads these items, they’re asked to indicate the answer that best fits their experience, but left unanswered are these points: what time of day? what kind of chair? what is the person doing in the chair? who is around that person? why is the person sitting for a long time? what is it about the pain that stops the person from sitting? what do they think is going on?

While the measure itself is based on rigorous methodology, has excellent psychometric properties and so on – it doesn’t investigate important dimensions that we need as clinicians to help this person perhaps alter their sitting tolerance.

Alternative measurement approaches are available: item response theory is one (click) and multi-level modelling is another (click) – but the former still considers latent traits (ie can we identify a general underlying response that underlies all the variability we see in the data), and multi-level modelling also assumes that the respondents still belong to a general population who will demonstrate similarities around the variable in question.

The problem is that people don’t always follow the rules. Here’s an example:

A woman I saw once had low back pain, and was very afraid to bend forward. She was particularly worried about bending down in the shower to wash her lower legs, and when she saw me she avoided putting her handbag on the floor because this would mean she’d need to bend down to pick it up.

To get around this concern, she’d learned to sit on the floor of her shower to wash her lower legs, used pull-on shoes with elastic laces, or court shoes for work, and she’d put socks and pantihose on while sitting on the floor.

At the same time, she was comfortable sitting for around an hour, was able to stand as a customer service person for an eight hour day, and was happy driving – but not happy about reaching into the back of her car (it was a two-door) because it meant she was bending.

For this woman, her score on the Oswestry was below 20% or considered to be “minimal disability” – and yet she was almost turning herself inside out to be able to do what mattered to her.

An idiographic approach to her situations looks a little more deeply at the function of behaviour in context. If we take a look at the amount of spine flexion within her activities of daily living, we can see that sitting on the floor to wash her legs, and to pull shoes and socks on involves just as much movement as if she was bending down. What was different? Well, she was really afraid she’d slip in the shower and land in an undignified heap on the floor, needing to be rescued – while being naked! She said she’d been told that she shouldn’t bend because she had a disc prolapse and she’d seen one of those spine models with the bright red disc bulge and thought this was going to be much worse if she bent over. She was very concerned about appearances as she worked in a customer service role, so developing a way to still get dressed while avoiding bending forward was really important to her – but it took her much longer to do, much more effort to do it, and she remained quite certain that this red jelly would ooze from her disc if she bent forward.

In a behavioural approach to pain management, it’s important to understand the antecedents and consequences of a behaviour, so we can understand what elicits the behaviour, and what consequences occur to maintain it. In this woman’s case, any context where she might need to lean forward – such as making her bed, picking clothes up from the floor, putting shoes and socks on from standing, picking her handbag up, reaching into the back of her car to fetch something – elicited a thought (image) for her of her disc oozing out. Combined with her interpretation of the advice not to bend when she first sought help, her response was one of fear – and one thing we learn very early on as humans is that we should avoid things that generate fear.

The consequences of her avoiding forward flexion were many: her fears weren’t allayed except in the moment, and she remained highly concerned about the disc bulge; she felt relieved in the moment as she avoided doing the movements she thought would harm her. This is negative reinforcement – fear (negative experience) is reduced (withdrawn) because she avoided the movement (relief – I’ve avoided a disaster!). She also avoided doing many things she’d enjoyed – like playing tennis (bending down to pick up a ball? No way!), picking her clothes up from the floor (she had a home helper do this, and do her washing), she’d changed the shoes she wore to avoid having to bend down to tie laces, and she sat on the floor of her shower to avoid having to bend down to wash her legs.

When we started to work on helping her move on with life, it was really important to understand the unique combination of context and function of her strategies for avoiding bending. Just telling her that her discs wouldn’t bulge out wouldn’t alter those powerful images in her mind! We can’t unlearn an association once we’ve learned it. And she’d been practicing this association between an image of disc bulge oozing and bending – and all the activities where we bend, and all the associations she’d made between jelly wobbling (because the disc is basically jelly, right?), and all the other things she knew about jelly – it’s not strong, it can smear over things, it wobbles, it can melt…. My approach was to help her experience doing without the dire consequences, starting from simple and moving to more challenging over time. More on this next week!

As clinicians, our words matter, as do the images and models we have in our clinics. We also must be mindful that the people we try to help will bring their history and the unique associations they’ve made between things they’ve been told, metaphors they’ve heard and the values that matter to them. Respecting all those vitally important and idiosyncratic aspects of being human is integral to a behavioural approach to pain rehabilitation. Let’s not put people into algorithms or groups or boxes, because if we take the time to learn about their uniqueness we can create more powerful – and fun! approaches to helping them live their lives again.

Fairbank J, Couper J, Davies J, et al. The Oswestry low back pain questionnaire.
Physiotherapy 1980;66:271–3.