The Use Of Orthotics To Treat Foot Conditions

What are Orthotics?

Over the years, orthotics have come to describe a wide range of products designed to provide foot support and comfort. Despite this range, a true functional orthotic (as developed in the middle part of the last century) is defined by a device that is formed from a mold of one's foot while that foot is held in a subtalar joint neutral position. The subtalar joint exists under the ankle joint, and allows for the foot to flatten and increase its arch depending on the direction of its motion. The neutral position is when the subtalar joint is not flattening (pronating) the foot, nor is it creating a higher arch (supinating). It has been well demonstrated that a wide variety of foot conditions are the result of poor mechanics at the subtalar joint. Hyperpronation occurs when the subtalar joint allows for excessive pronation than anatomically typical. The opposite occurs if too little pronation is available, as the foot becomes 'cavoid', or high arched, although this is far less common. Many foot problems occur directly as a result of hyperpronation, including plantar fasciitis, posterior tibial tendonitis, Tarsal Tunnel syndrome, hammertoes, bunions, and neuromas. An orthotic will be effective by controlling this hyperpronation, thus eliminating the underlying cause for numerous foot conditions. Used alone for treatment, the orthotic will not likely be beneficial as the inflammatory (pain) part of these conditions still need to be addressed. However, as part of a multifaceted treatment plan in which the orthotic is used for long term structural support, the orthotic is likely to provide significant benefit. The orthotic design must accurately capture a person's specific subtalar joint in a neutral position in order to provide the maximal amount of anatomic structural support. By doing this, the orthotic will reduce hyperpronation, allow the foot and leg to function more anatomically, and significantly reduce structurally caused foot problems. Orthotics are usually made of a thermoplastic, but other composite materials can be used to make them thin enough to fit into women's dress shoes. Fabric topcovers can be used, not so much to increase comfort as to provide a platform to apply modifications to help the end of the foot. For example, an orthotic itself runs from the heel to just in front of the ball of the foot. To help offload the ball of the foot further for certain conditions, more accommodative padding is needed further down along the foot beyond where the orthotic itself ends. This adds further benefit to the orthotic's function. Without a topcover, this padding cannot be attached to anything. In most cases though, topcovers are not necessary and their absence helps the orthotic fit into a wider variety of shoes. As the orthotic is a prescription device, a full biomechanical exam by a foot specialist is needed in order to get the prescription 'right', as some patients require more adjustment in aligning the back of the foot with the front of the foot by changing how the orthotic is angled, and certain conditions require more dramatic modification to the usual cast. These more dramatic modifications can include wedges, cut-outs, higher heel cups and other significant changes to the orthotic's plastic shell.

What about over-the counter inserts?

Over-the-counter inserts have been used for many years for a variety of purposes. In general, they provide decent padding and cushioning to the arch and sole of the foot, reducing shock and in some designs providing limited structural support. Typically, these devices consist of felt, foam, gel, or polymer padding designed to push bulk into the arch. Some designs are plastic, emulating orthotics in appearance, but not function. These inserts have firmer support, but are not as well tolerated as the unyielding plastic can irritate the tissue on the bottom of the foot as it is not truly molded to the wearer's specific foot, much less to a proper subtalar joint neutral position. In certain conditions that simply need further cushioning or minimal support, over-the-counter inserts are a fine choice for therapy, and present a viable option as an initial treatment for conditions requiring further support as long as functional orthotics are eventually used for long term control. These inserts can potentially belong to a class called accommodative orthotics. Although this generally implies inserts made of a mold of the foot without placing it into a subtalar joint neutral position, the definition has seemingly broadened to include most all over-the-counter inserts and soft orthotic-like inserts. These devices as a whole increase shock absorption, benefitting high arched feet. They also reduce pressure, beneficial for diabetics and those with painful rheumatoid arthritis. However, they are insufficient in providing adequate structural support over the long term, and are far inferior to traditional orthotics for that specific purpose. In essence, over-the-counter inserts have a notable role to play in a foot treatment course, but are insufficient for those who need full biomechanical control.

Who Provides Orthotics?

Many providers now produce orthotics or inserts claiming to be orthotics. Beyond podiatrists, some orthopedic surgeons, and traditional orthotists/pedorthists, orthotics are offered by physical therapists, chiropractors, shoe stores, and self-described insert stores. As with anything, quality is directly related to the training of those providing the service. As long as a full biomechanical exam has been performed, and the foot has been casted in a subtalar joint neutral position, the orthotic will generally turn out sufficient for use. I have definitely seen good orthotics from therapists and chiropractors due to their knowledge of general biomechanics. On the other hand, I have also seen accommodative padded inserts passed off as functional orthotics as well. Unfortunately, many non-traditional retail store providers of orthotics and inserts have little understanding of how the foot actually functions, and cannot make an accurate assessment as to any compounding foot problems that may need to be addressed in the orthotic fabrication. The devices produced are often inadequate to provide exacting support, and, although not uncomfortable initially, tend to fail in the long term. This is often at great financial cost. In some cases, customers are given what they are told are orthotics, when in actuality they are simply over-the-counter inserts that are matched to a person's shoe size. Some retail locations charge hundreds of dollars for these devices, where actual orthotics may be covered by insurance, and may not even be as expensive if not covered.

What Conditions Do Orthotics Benefit and What Are Their Limitations?

As discussed above, orthotics will benefit numerous conditions in which hyperpronation plays a central role in the overall development of the condition. By achieving maximal control of the subtalar joint, orthotics perform more effectively and efficiently than other insert designs. Orthotics may also have a role in the treatment of conditions requiring increased shock absorption, as seen with high arched feet where plantar fascitis is a direct result of the poor shock absorption of higher arches. When soft inserts do not provide enough shock absorption in these cases, the stiffness of these inserts absorbs the weight-bearing energy, and disperses them into the orthotic plate itself rather than the sole of the foot. Orthotics are also used to transfer weight-bearing pressure in cases where painful calluses, pressure sores, or arthritic joints require exacting structural support to avoid surgical intervention or more significant complications. In these cases, taking weight off of the specific part of the foot that needs to be addressed demands an exacting casting technique and knowledge of how this 'de-weighting' will effect the rest of the foot. Finally, orthotics are used successfully to reduce the arch fatigue created by hyperpronation, which can sometimes cause knee strain, as well as hip and back problems if severe enough. This fatigue is especially seen in kids, and the use of an orthotic in a flexible flat foot will eliminate the need for reconstructive surgery for a majority of these pediatric cases.

Orthotics do have their limitations, and are certainly not a panacea for all foot pathology. In nearly all cases they are ineffective in reducing deformity that has already developed. For example, many people have been told by retail stores selling inserts that their 'orthotics' will reduce hammertoes and bunions. This is simply not true, as even a functional orthotic will only reduce the progression of such deformities by controlling the underlying factor: flattening of the feet. The deformity itself is only correctable via surgery. Orthotics are also ineffective in people with a rigid flat foot deformity, as there is little pronation left in those feet to support. In general, functional orthotics should only be used in conditions that have a foot structural cause, are not yet completely developed from an bone standpoint, and are from feet flexible enough for the orthotic to allow for motion reduction at the subtalar joint. Otherwise their benefit and effectiveness may be doubtful.


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Dr. Kilberg provides compassionate and complete foot and ankle care to adults and children in the Indianapolis area. He is board certified by the American Board of Podiatric Surgery, and is a member of the American Podiatric Medical Association. He enjoys providing comprehensive foot health information to the online community to help the public better understand their feet. Visit his practice website at http://www.inpodiatrygroup.com