EVIDENCE - BASED DESIGN
The use of orthoses can be traced back to ancient civilisations. However, it took until the 21st century when modern material science enabled us to produce highly precise, bespoke orthoses underpinned by an improved understanding of biomechanics.
The exact mechanism of action through which orthoses produce a therapeutic outcome is still being debated and developed. This uncertainty has left the door open for abuse in marketing claims and huge variability in the quality and effectiveness of the orthoses on the market.
There are several reasons for this poor understanding of orthoses’ cause and effect. Not least, because of the multifactorial nature of injury and the variety of orthoses options. However, research does consistently show orthoses do elicit a therapeutic response. But, if we are unable to consistently do this, or understand the reason why this is happening, we are just getting lucky.
Historically, we viewed orthotics through a kinematic lens and worked around the idea that foot orthoses held the foot in a certain position or changed alignment. Unfortunately for this idea, the foot functioning around a neutral position is not supported in any population in any study. Furthermore, we have plenty of studies which show orthoses do not consistently change foot position in a diverse population.
Understanding the cause and effect of orthoses is crucial if we are going to generate consistency in our prescribing and successfully achieve our outcome measures.
Moving away from attempting to understand orthoses through kinematics and looking at what orthoses do in all people all the time – they alter kinetics. Even when there is no visible change in position orthoses can significantly alter kinetics.
Interesting, but how does this help you treat pathology?
In respect to musculoskeletal injuries and as a generalisation, injury occurs due to loading a tissue beyond its capacity. With our orthotics we can use Sir Isaac Newton’s Laws of Motion to manipulate the ground reaction forces in a considered and repeatable way. Doing this, we can manipulate forces to change joint moments and loading in selected tissues. An orthotic should aim to load specific tissues within their current capacity to handle the load being placed upon them.
Orthoses are a mechanical device and should be considered as part of a holistic patient centered approach to injury with wider consideration given to biopsychosocial factors. Understanding the function of orthoses will make them a key part of your treatment plan and a powerful tool when considering load management and rehabilitation.
At MM Podiatry & Orthotics we will continue to use the most up-to-date evidence-informed research to ensure the orthoses you supply will successfully treat your patients and we will continue to go where the evidence takes us.