Valeo PT offers Sole Supports Custom Foot Orthodics

Sole Supports - Advancements in Orthotics

Valeo PT now proudly offers Sole Supports Custom Foot Orthodics.

This is the first in a series of articles that deal with the theory and reasoning behind using Sole Supports.

Advancements in Custom Foot Orthotics

Dr. Stuart Currie, DC

The biomechanics of custom foot orthotics is a fascinating and ever evolving field. From the descriptions of the foot as a biomechanical structure in the 1970’s (1) to the complex imaging and gait analysis tools in use today, our understanding of the foot and how it interacts with our world has come a long way. In the last few years, great strides have been made in attempts to quantify, visualize and understand the movements of the joints of the foot and the forces involved (2-4). As chiropractors, many of us have an interest in the way that foot function can affect human health from the bottom to the top of the kinetic chain.

Unfortunately, the prescription of custom foot orthotics has not been accompanied by a wealth of empirical data supporting positive clinical outcomes (5). In fact, there is much evidence that shows just the opposite – that a prefabricated “off the shelf” orthotic can be more effective than a “custom made” device in the treatment of plantar fasciitis (6). As clinicians with a direct interest in the biomechanical wellness of our patients, this should concern us greatly.

Foot orthotics are prescribed and dispensed by many different providers, each having their own view on how to address biomechanical dysfunction. The domain of foot orthotics has traditionally been that of the podiatrist. Chiropractors, physical therapists, and pedorthists, have joined the ranks of clinicians who dispense foot orthotics for maladies including but not limited to plantar fasciitis, shin splints, bunions, hammer toes, Achilles tendonitis, and so on. Many chiropractors prescribe orthotics for problems higher up, including knee pain, hip pain and SI joint dysfunction and back pain. It only makes sense that providing a solid foundation for locomotion and shock absorption could have benefits for the entire body. What is crucial is that each and every clinician involved in the treatment of the foot, have a thorough understanding of the forces and joints involved and how to change those forces for the good of the patient.

Custom made foot orthotics come in many shapes and sizes. Casting techniques can vary considerably as well, from foam boxes to digital force plates to plaster casting. A detailed analysis of each method goes beyond the scope of this discussion, but it is enough to realize that the clinician must make an informed decision when it comes to choosing the right type of orthotic for a specific patient and condition. For example, one should question the logic of taking a 2 dimensional image of the bottom of the foot, in order to make a 3 dimensional orthotic. How is that 3rd dimension (height of the arch) recreated at the orthotic lab? In addition, techniques that take an imprint or mold of a patient’s foot simply by standing in a foam box should be questioned. If that is an imprint of a pathological foot, how is the orthotic lab making decisions on where the foot should be? A thorough biomechanical evaluation of the foot with emphasis on a clinical decision to enable a more corrected position is necessary. A common question is often asked in the design of an orthotic: should a foot orthotic be rigid or flexible? This question misses the point. The question should be: how much force does a curved piece of plastic need to exert in order to control the foot during the gait cycle? The answer will depend on many factors, including body weight, foot flexibility, and activity levels, just to name a few.

While foot orthotic intervention can have a profound effect on a patient’s life, the reasons are much more complex than simply blocking pronation.

New Strategy in Foot Correction. MASS position: Maximal Arch Subtalar Supination with lowered head of first, rearfoot and forefoot flush to floor.

True biomechanical correction requires a cast of the foot in a very specific (corrected) position, and a device that flexes with the foot during the shock absorption phase of gait, while providing a rigid lever for propulsion during toe off and walking. These two functions are quite dichotomous and require vastly different considerations. Fortunately, advancements in our understanding of the forces involved during gait, and improvements in orthotic technology are allowing practitioners to take full advantage of these devices for the benefit of our patients.

Recent studies are beginning to show that orthotics differ in their ability to correct pathology and some can have a positive effect on the gait cycle (7). Improvements in plantar pressures and postural stability are being shown with certain types of orthotics (8). These orthotics are in full contact with the arch at all times during the gait cycle and are calibrated precisely to the patient’s body weight, foot flexibility and arch profile. This is encouraging for the practitioner who provides services to patients based on their knowledge of biomechanics and the available evidence. A recently published article in BioMechanics provides a more thorough discussion of the theories involved and the advancements being made in the development of orthotics (9).

As is the case with all health care interventions, it is the clinician’s responsibility to maintain a certain level of education and knowledge with regards to the techniques or devices involved. The prescription of custom foot orthoses is no different, and is an intervention that requires an acute awareness of the biomechanics of the foot. Changes in technology have brought many improvements to the field of foot biomechanics, and a well educated provider will achieve a high level of success in the treatment of foot pathology to the great benefit of their patients.

Dr. Stuart Currie DC, maintains a private practice in Denver, CO.

Dr. Edward Glaser DPM, founder and CEO of Sole Supports Inc., a custom foot orthotic company, will be giving a one day seminar sponsored by the CCA on June 16, 2007. You will find his lecture on the biomechanics and the 35 common diagnoses that can be treated with foot orthotics fascinating. His “treat the cause and not the symptom” parallels chiropractic philosophy and will enable you to achieve better results in your clinical practice.

References

1) Root, M.L., Orien, W.P., Weed J.H.: Normal and Abnormal Function of the Foot, Clinical Biomechanics Corp, Los Angeles, 1977.

2) Payne, C.B.: The Past, Present, and Future of Podiatric Biomechanics. J. Am. Podiatr. Med. Assoc., 88(2): 53-63, 1998.

3) Cornwall M.W., McPoil, T.G.: Three-Dimensional Movement of the foot during the stance phase of walking. J. Am. Podiatr. Med. Assoc., 89(2).: 56 – 66, 1999

4) Huson, A.H.: Biomechanics of the tarsal mechanism: a key to the function of the normal human foot. J. Am. Podiatr. Med. Assoc. 90(1).:12-17, 2000.

5) Landorf, K., Keenan, A.M.: Efficacy of foot orthoses. What does the literature tell us? J. Am. Podiatr. Med. Assoc., 90(3).:149-158, 2000.

6) Pfeffer, G., et al: Comparison of Custom and Prefabricated Orthoses in the Initial Treatment of Proximal Plantar Fasciitis. Foot & Ankle Int. 20(4):214-221, 1999.

7) Hodgson, B., Tis, L., et al. The Effect of 2 Different Custom-Molded

Corrective Orthotics on Plantar Pressure. J. Sport Rehabil. 15: 33-44, 2006.

8) Cobb, S., Tis, L., and Johnson J.: The Effect of 6 Weeks of Custom-molded Foot Orthosis Intervention on Postural Stability in Participants with >7

Degrees of Forefoot Varus. Clin. J. Sport. Med. 16:316–322, 2006.

9) Glaser, E., Bursch D., and Currie S.: Theory, Practice Combine for Custom Orthoses. BioMechanics. 8(9):33-39, 2006.