How Orthoses Work

There are several reasons why you may have been issued a pair of Footbionics. Many foot or lower limb injuries respond quickly to orthotic therapy. Orthotic devices are usually dispensed as a treatment for pain or discomfort that you may have been suffering. Orthoses are also used to correct posture or abnormal foot position as a preventative measure. This is based upon the theory that an abnormal foot position will more likely lead to pain or injury.
Excessive foot pronation is considered to increase tissue stress, and therefore controlling this movement is often what your podiatrist will focus upon.
Whilst an orthotic device is usually used to control this motion they are often used to simply support the bony structure of your foot. By supporting the foot, tissue stress can be reduced and pain relieved. However there are several recognised ways in which you may benefit from using orthotic devices.

Foot Supportfoot support
Orthoses can simply support the plantar surface (undersurface) of the foot and thereby help to reduce deformation on weightbearing. By maintaining and supporting the foot tensile strain through the sole is reduced. This concept is more “accommodative” support as opposed to “corrective” repositioning of the foot. So often merely supporting the arch can be of significant benefit to an injury or condition.

Pressure reductiontekscan wireframe 1 1
As orthoses support the foot they will also affect the regional pressures and loading through the sole of the foot itself. The concept of subtly adding more pressure to the arch will for example reduce pressure in the heel and forefoot. Thus an orthotic device can redistribute pressure from an area which can also immediately reduce pain. This is more difficult to measure with out pressure measuring devices however it can provide dramatic and immediate relief of symptoms.

Motion controlmotion control
This is the most commonly thought or measured way in which an orthotic can help. Many podiatristswill use treadmill and video equipment to measure the effect of footwear and orthoses on foot motion. Pronation is the movement of the foot rolling inward with this also causing an arch lowering effect on the foot. Excessive pronation of the foot is considered to be a causative factor for many injuries that you may have – particularly overuse injuries or injuries related to repetitive overload. Excessive foot pronation can be reduced with an orthotic device. Generally the firmer the material the more foot control is achieved.
Shock absorptionshock absorbtion
As well as improving foot motion, orthotic devices can also help reduce the peak pressures or forces beneath your feet. When you contact the ground when walking there is 1.5 times bodyweight that are transmitted through the heel with each impact. There is 3 times your bodyweight at heel contact when you run. Think of the orthotic as working by cushioning and improving shock absorption. Shock absorption has long been seen as a critical element in injury prevention. The foam materials that your Footbionics are constructed from are excellent in providing additional cushioning to dampen these forces.
speed of motionSpeed of foot motion
Orthoses are important in controlling the speed (velocity) of your foot and lower limb movements. If movement is rapid and jerky, muscles generally have to work much harder to decelerate and provide control. Imagine if your foot just slapped down rapidly on impact, as opposed to a more gradual or controlled landing. Orthoses can control the speeds of such movements well. Dampening the speeds of these movements will assist in injury reduction. Footbionics attempt to control foot velocity by using foams that dampen this movement. Their motion controlling shape also plays a critical role.

timing of motion1Timing of foot motion
The timing sequences of foot and lower limb motion have more recently been investigated particularly in lower limb injuries. The specific timing of movements and foot position follows a general pattern. As an example, maximum knee flexion should occur at the same time as maximum foot pronation.  If these movements are “out of sync” then pain or injury can occur. By preventing abnormal foot motion, Footbionics can help improve this foot and lower limb synchronisation.

Proprioceptionproprioception 1
Like balance your ability to perceive foot position is critical for any weight bearing activity. The type of surface that you stand on has been shown to decrease or increase stability. Textured insoles rather than smooth insoles have been shown to increase this positional awareness. This could have huge implications for injuries such as ankle sprains where balance is critical to avoid this injury. This is another reason why many of our Footbionics models are manufactured with a textured “polo knit” or brushed nylon fabric as found in many athletic shoe sockliners.