Orthotic Therapy

Orthotic therapy may be advised to treat some injuries. For example, if the injury is related to adverse structural / movement related issues, a corrective in-shoe device (orthotic) is beneficial in addressing the adverse forces associated with adverse structural alignment / movement. Often these types of forces are related to pronation (foot rolling inwards) which could be excessive (i.e. an individual exhibiting a high supination resistance force) and / or out of phase (lasting too long in the gait cycle). In some cases the injury may be the result of an adverse degree of supination (foot not rolling inwards enough). The prime structure affecting the degree of pronation & supination is the Talus bone, which contributes to the Sub Talar Joint (STJ).

There is no muscle and thus subsequent tendon directly controlling the function of the Talus bone, thus exercises have limited impact on excess degrees of its movement... thus why an orthotic is particularly beneficial in addressing injuries related to these type of movements.

• Supination and Pronation in relation to the left foot:

- There are various types of orthotics to suit various lifestyle factors / conditions (i.e. Rheumatoid Arthritis), body type (i.e. weight), sporting activity (i.e. running) and footwear (i.e. women's court style shoes).

- With the above in mind, orthotics thus can come in varying widths, lengths, thickness and flexibility to suit the individual's requirements. Thus a custom orthotic is usually more beneficial as it adequately represents the nature of the individual's foot & footwear. A 3D representation (i.e. a mold or impression) must be obtained in the process to adequately aid in conformity, support and fit.

- However, I believe the orthotic should have adequate flexion for the individual, as the foot was naturally designed to flex whilst walking and running. In other words, orthotics should not be rigid devices which block the foot with limited motion. With that said, what may be regarded as (acting) “rigid” for one individual, may not be (acting) “rigid” for another – based on the individual’s supination resistance force (the force required to resupinate the foot i.e. from a pronated position) and body weight. For example, an individual exhibiting a high supination resistance force (see picture below) will require an orthotic of greater rigidity (to aid in greater support required - to thus reduce greater adverse / pathological forces) than an individual exhibiting a lower supination resistance force (who requires less force from the orthotic to reduce potentially adverse / pathological forces). Motion (i.e. pronation) is needed to some degree as a natural means to absorb shock / forces (and adapt to the terrain)... thus the orthotic does need to flex – but do so in relation to the individual’s supination resistance force (test) and body weight.

- There is another variety of orthotic which I call Thermo Moldable Orthotics. This variety is prefabricated according to size but they can be heated with a heat gun to then be molded to the individual's foot whilst in the shoe - thus they are semi-customised. This variety is suitable for milder amounts of correction / support or for shorter term use (i.e. children going through growth spurts). This variety is cheaper than the custom variety.

 

♦♦♦ Hence, my objective behind orthotic therapy is to reduce the degree of adverse structural movement / positioning of the foot but more importantly the focus is on reducing the degree of adverse forces directed to various parts of the body (i.e. a tendon, muscle or joints), subsequently limiting a causative factor of injury... or future causative factor...

• The above picture is of an individual with a medial deviated Sub Talar Joint (STJ) axis (note the medial / inside contours of ankles - they are bulging inwards)... this will create a high degree of pronation related forces (i.e. medial / torsional and eccentric related forces) which will potentially adversely affect joints, tendons and muscles. This case would exhibit a high supination resistance force (force required to resupinate the foot from the above pronated position). Hence for this individual to be effectively treated, a device (i.e. orthotic) is required to reduce the supination resistance force (hence reduce force directed to bone and tissue i.e. eccentric loading force directed to Posterior Tibial Tendon) and provide a more ideal alignment (positioning) of the STJ and foot... so this individual doesn't meet their injury threshold / limit too soon.

 

One should also be aware that there is unfortunately inappropriate foot devices advertised claiming to address / resolve adverse structural alignment and function. Hence I have outlined these issues and why some products have flawed reasoning and principles. These are outlined in the next section... Snake Oil Promotions...