Yesterday at the Annual Conference in Sports & Exercise Medicine in London I gave a workshop alongside Dr Simon Lack, a Physiotherapy colleague who has a PhD in patellofemoral pain (PFP). The topic we approached was essentially the age old debate: when managing patients/athletes with PFP do we focus on a top down (proximally driven) approach or a bottom up (distally driven) approach? Or both? More importantly, as clinicians how to we make evidence informed decisions on this? [The conclusion won’t surprise anyone – an interdisciplinary team approach is king].
Simon covered the top end. My part of this workshop was therefore simple; when should we consider foot orthoses in these cases? We often fall into the following habit: (1) A patient with PFP presents to clinic (2) We assess the foot (3) We look for the way the foot may have contributed to/caused the symptoms (4) We make our decision on whether to intervene based on this thought process alone.
Whilst there is some Level 1 evidence that there is a relationship between foot posture and PFP the waters are really rather murky. Fortunately, we may not have to look through this particular lens. We can instead just purely look at the evidence base for foot orthoses use in patients with PFP; so essentially consider the effects rather than the mechanisms.
Two papers have been published in recent years which essentially put in writing what are considered to be the best practices in treating PFP in the context of the current evidence. With respect to foot orthoses the conclusions are clear:
“The use of foot orthoses is supported, particularly for short term pain relief” (reference, reference)
What is notable, however, is that whilst foot orthoses are recommended, the responses to them are person specific and the outcomes are variable. A paper published in 2010 (reference) found something interesting – when giving foot orthoses indiscriminately to all, with no consideration of foot posture or any other patient characteristic, then the chance of success was 40%. So is this a reasonable approach to adopt clinically? Or do we need a better approach than just giving them to all patients with PFP, and instead try and predict who may benefit from them (and who may not) beforehand? For me, it is the latter. Particularly as the same paper reported that this 40% success can perhaps double to 80% if other characteristics were present.
Enter the “treatment direction test” – which was first discussed by Bill Vicenzino and colleagues and referred to low dye taping. If there is an immediate reduction in pain when performing a provocative test with tape in situ that patient is more likely to be a good candidate for (i.e. benefit from) foot orthoses. Barton et al. (reference) also echoed this process, but described the method of asking the patient to do a single leg squat on top of an orthosis.
Then there is the midfoot width test, where the change is measured (at 50% of the foots length) between non weight bearing and weight bearing conditions. Research shows those with values of 11mm or greater are more likely to benefit from foot orthoses (reference).
So what can we summarise? Personally, I tend to get referred PFP patients quite early by my physiotherapy colleagues. Safe in the knowledge they will be having all of the proximal considerations addressed, I usually measure their midfoot width (hanging sit-to-stand) and also low dye tape them at the end of the first session. If they respond well to the tape (feedback after 2/7 of ‘normal life’ an approach we often take) and their midfoot width change was greater than one centimeter I tell them it is sensible to wear some orthoses in the short term; and usually suggest 2-3/12 of a device and we will then review things (along with their physio). I try and be as honest and transparent about what we are doing and why.
I try to emphasise to the patient that they are to consider the devices as a short term intervention for pain relief, in a similar way they would view paracetamol for a headache. They would never have the expectation that they need to take paracetamol daily ad infinitum, and the same mindset should be applied to foot orthoses for PFP in most cases. They are rarely a life sentence, and if we are taking this approach then we should stress we are not issuing devices with the belief they are “correcting” or “re-aligning” anything, we are simply trying to modify symptoms.
Not perfect, but hopefully ethical and evidence based. I look forward to any thoughts and discussion.
