Why do many Doctors not understand Excessive Foot Pronation
Why do many Doctors not understand Foot Pronation and what to do with it.
On a daily basis sports Podiatrists assess and diagnose in an attempt to establish contributors to injury. When assessing lower limb injuries one of the most common observations is excessive dynamic pronation. But why is this misinterpreted as the cause of pain? Why are the treatments that many practioners and doctors suggesting not effective, not desirable and not beneficial to the patient? Usually this is because a lot of the reasearch has improved our understanding of the causes of musculoskeletal injury and pain, and many practitiners do not have a good understanding of this complex and challanging area of medicine, and do not keep up to date in this field.
- Prevention of Lower Limb Overuse Injuries with Orthotic Therapy
- Treating Patellofemoral Pain With Orthotics: Research Review
- Intrinsic Foot Muscle Strengthening: A Comparison of Short Foot and Toe Curl Exercises
This article will discuss the effectiveness of various external controls in preventing excessive pronation.
What Is Pronation?
Now, this should not come as a surprise to anybody but foot pronation is in fact a very normal motion of the foot. It is required for shock absorption during normal walking and running gait.
Pronation is a triplanar movement required for walking, and is the combination of rearfoot eversion, midfoot abduction and talocrural (ankle) dorsiflexion.
This movement is required during stance phase to allow for normal patterning. Pronation is not a bad thing, however, where we get into trouble is when there is a excessive increase in the forces required to move the foot and leg through the necessary movements of pronation and supination.
Why Do We Want To Prevent Excessive Pronation?
There are obvious reasons why a practitioner would want to limit excessive pronation in an athlete, however it is critical to understand what they are actually doing. Although "Excessive foot pronation" has been shown to be correlated with the incidence of the following (to name but a few): Metatarsal stress fracture (Mazrahi et al., 2000), Plantar fasciitis (Pascual Huerta et al., 2008), Achilles tendinopathy (McCrory et al., 1999), Patellar tendinopathy (van der Worp et al., 2011), Medial tibial stress syndrome (Moen et al., 2009), Patellofemoral pain (Cheung et al., 2007), there are many other recent studies showing pronation is unfairly blamed as the main contributing factor in many injuries. In fact, some injuries require an increase in pronation to help improve. It is common is sports podiatry practice to utilise taping techniques, orthoses or footwear as a component of an over-pronation management program (Cheung et al., 2011).
However, do you know what devices of these are the most effective and controlling excessive pronation?
Research Into “Anti-pronation Devices”; why this type of research is not relevant to modern practise
The following reasearch shows a complete misunderstanding as to the main contributing factors to foot and lower limb injury. The angle of the heel (calcaneus) ..............
A recent meta-analysis by Cheung and colleagues (2011) evaluated the effectiveness of different ‘external controls’ for controlling excessive pronation. This allowed the authors to compare the efficacy of a number of interventions for preventing excessive pronation. These included:
- Therapeutic Adhesive Taping (including Low-Dye and High-Dye taping techniques)
- Foot Orthoses (including custom moulded and prefabricated)
- Motion Control Footwear
The authors were also able to draw conclusions on the effectiveness of individual techniques i.e. low-dye vs. high-dye taping. The main outcome assessed was mean reduction in calcaneal eversion i.e. the most easily assessed component of pronation. The results are shown graphically below:
Thus, the results show that the all 3 options were similarly effective for controlling rear-foot motion, as you will notice only about 0.5 degree difference between them. This may simply be a measurement error due to the lower quality of included studies.
Additionally, the authors were able to evaluate subsections of the devices. What should come as no surprise is that the authors found that custom orthoses were more effective than prefabricated orthoses (but only by about 0.27 degrees). What may surprise some practitioners, is that the studies showed that low-dye taping produced no statistically significant change in calcaneal eversion. This is striking given that low-dye taping is one of the most popular techniques among clinicians. This supports the findings of a systematic review which showed low-dye taping produced no significant changes in rear-foot motion and only small changes in navicular height (Radford et al., 2006). However, other techniques (high-dye and stirrups) were quite effective in controlling pronation (mean change=4.62°). The effectiveness of taping techniques over a period of time was not evaluated, and should be questioned.
Clinical Implications of This Research
- There was a lack of high-quality randomised controlled trials in this area, despite the fact that they are feasible. Thus, the findings should be taken with caution
- The 3 options were similarly effective for controlling rear-foot motion (particularly if you exclude low-dye taping)
- The authors suggest the selection of anti-pronation intervention should be based on individual patient characteristics, type of activity and personal preference
- If you are going to utilise taping to control excessive pronation; high-dye or stirrup techniques seem more effective
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Pascual Huerta J, García JM, Matamoros EC, et al. Relationship of body mass index, ankle dorsiflexion, and foot pronation on plantar fascia thickness in healthy, asymptomatic subjects. J Am Podiatr Med Assoc 2008;98:379–85.
Radford JA, Burns J, Buchbinder R, Landorf KB, Cook C. The effect of low-dye taping on kinematic, kinetic, and electromyographic variables: a systematic review. J Orthop Sports Phys Ther. 2006;36(4):232-41.
Van der Worp H, van Ark M, Roerink S et al. Risk factors for patellar tendinopathy: a systematic review of the literature. Br J Sports Med 2011 45: 446-452.