How is it possible that those 26 bones and 33 joints with over 100 muscles and tendons function together every single day without even an acknowledgement from ourselves?
That’s until you eventually develop some ache and discomfort! The Foot Posture Index (FPI) provides us with a way to assess and understand how your foot interacts and presents during the standing, weight-bearing state – that’s whether your feet are aligned, overpronated, or supinated. What the Index and Score Ultimately mean and what can be practically done with it – are explored below.
What Does the Foot Posture Index Assess?
The FPI was introduced in the early 2000s by the late Dr. Anthony Redmond and associates as a tool to provide objective foot posture evaluation, both clinically and in the research context. Before the FPI, clinical judgement was generally relied upon.
In contrast, the FPI simultaneously assesses six objective features of foot and ankle biomechanics in the weight-bearing phase, enabling more reliable and reproduce-able measures. What does it score in terms of specific values?
Each component measures different features of foot posture: * Talus Head Palpation: assesses the prominence of the head of the talus (a vital ankle bone) either on the inner or outside of the foot.
- Supra and Infra Lateral Malleolar Curvature: checks the shape of the contour on the outside aspect of the ankle bone as it looks from behind.
- Calcaneal Frontal Plane Position: tests to see if the heel is tilted inward or outward as it viewed from directly behind.
- Talonavicular Bulbousness: is a check of the prominence (or lack thereof) of the bone in the front, upper portion of the mid-foot.
- Medial Longitudinal Arch Height: measures how low or high the inside arch is of the foot when viewed from the side.
- Forefoot-to-Rearfoot Abduction or Adduction: ensures that the front portion of the foot is aligning appropriately with the heel portion of the foot as viewed from above. Each of these variables is scored from -2 (severe) to +2 (mild) in addition to their relative position – allowing for total score between -12 (highly supinated) and +12 (highly pronated)
Why is foot posture important (even when my foot doesn’t hurt)?
Many often perceive the foot as isolated from the rest of the body – it’s the foundation of everything. As the first point of contact when you move through life, your foot sets the stage for the movement of the entire Kinetic Chain; comprising the foot and ankle, knees, hips and spine. If the foundation isn’t right then it will have repercussions throughout the entire structure, in even sometimes unrelated ways.
What can overpronated and supinated feet lead to?
When feet are in a state of overpronation the foot and ankle roll inwards with every step you take, resulting in an excessive internal rotation force being applied throughout the entire leg and into the hip and knee. If these joints were already vulnerable this will have significant implications. In the knee, for example, excessive pronation can increase pressure on the outer front surface of the kneecap causing Patellofemoral Pain Syndrome.
Further research has also highlighted that overpronating individuals are more likely to place excessive stress on the medial section of the knee joint. When the foot excessively pronates this leads to a subsequent increase in the rotation of the thigh, which can cause altered stresses around the lateral thigh that could contribute to lateral hip discomfort and pain as well as Iliotibial band syndrome (ITBS). What challenges are faced with the development offlat and high arched feet?
Flat feet and high arches are two ends of the foot posture spectrum. When feet develop into a state of flatness over time they have very little inherent ability to act as shock absorbers during each gait cycle; they offer less efficient dampening of ground reaction force. Therefore, the forces pass up through the entire lower leg into higher joints such as the knee, which is often painful, especially when spending extended periods of time stood or walked on hard surfaces.
Those who suffer with high arched feet will also find that forces are more directly transmitted up through the body; the stress becomes concentrated in the forefoot and heal and increases the risk of stress fractures or pain through the heel of the foot, and inflammation of the tissue between heel bone and toe bones (Plantars Faciitis). Both ends of the spectrum not only result in pain but will alter mechanical integrity of the entire lower limb and pelvis, increasing the risks of future injuries and limitations.
How the Foot Posture Index Is Used
The Foot Posture Index is applied in a variety of settings by both clinicians and through in-depth, individual assessment, to help guide treatment decisions.
If You Have Had An Assessment And Score If you have had a Formal FPI performed, then the scores in isolation only tell part of the story, particularly compared to how you feel when performing the specific activity. For example, a score of 7 with a young patient who runs a 2.5hr Marathon will be treated with differently to a 7 on a septagenarian. However as a generalisation: * A low score or any negative score implies the foot issupinated * A Score from 0 to +5 indicates neutral foot type * A positive score of+6 – +9 suggests an overpronated foot * A score of +9or higher indicates a severely pronated foot.
What can you do with this information?
Regardless of whether the FPI indicates that you are tending toward a flattened or high arched foot posture, there are always actions which may be taken: * Wear Appropriately Fitting footwear:Shoes are an important structural support for your feet. A good support willhelp to maintain a neutral alignment when it is under load, thereby aiding in preventing abnormal motion which occurs as result of flat and high arched feet.
- Strengthen the Intrinsic Foot Muscles: This can be achieved with a variety of simple yet effective toe and arch based exercises including the short-foot exercise. The intrinsic muscles assist with maintaining arch stability.
- Stretch your Calf Muscles: Tight calf muscles can contribute to the tendency to overpronate the foot, so regularly stretching this muscle group can help reduce this tendency and the associated strains on the foot and ankle, heel and arch regions.
- Consult a professional:If you find that you are experiencing foot pain or are concerned that you might have a foot-type at the extremes of the spectrum.
Then consulting with a Podiatrist and/or Physiotherapist who is well-versed in foot posture assessment will be able to give you personalised recommendations and treatment plans, which will include footwear recommendations and potentially the Prescription oforthoticsif required. Although orthotics may sound intimidating they are essentially a shoe insert which provides structural support to maintain the Foot in a neutral position when it is under stress, which reduces the stresses through the entire foot & ankle structure as the FSI measures when used as one part of a comprehensive assessment tool.
Taking the time to analyze foot posture may seem minor, but in reality it may prove crucial to your future comfort and mobility.