Articles for March 2012

Differences in Orthotics for Runners

This month’s guest blogger, Dr. Noushin Shoaee, DPM, is here to explain the differences in orthotics for runners.

What are Orthotics?
Orthotics are shoe inserts that are intended to correct an abnormal, or irregular, walking pattern. Orthotics are not truly or solely “arch supports,” although some people use those words to describe them. They perform functions that make standing, walking and running more comfortable and efficient, by slightly altering the angles at which the foot strikes a walking or running surface. Orthotics take many forms and are constructed of various materials. All are concerned with improving foot function, and minimizing stress forces that could ultimately lead to foot deformity and pain.

Orthotic Materials:
Rigid Orthotics – These orthotics are chiefly designed to control motion in two major foot joints. These devices are long lasting, do not change shape, and are usually difficult to break. Strains, aches, and pains in the legs, thighs and lower back may be due to abnormal function of the foot, or a slight difference in the length of the legs. In such cases, orthotics may improve or eliminate these symptoms, which may seem only remotely connected to foot function. This material is best for motion control, but it gives the least amount of shock absorption.

Soft Orthotics – the second, or soft, orthotic device helps to absorb shock, increase balance, and take pressure off uncomfortable or sore spots. It is usually constructed of soft, compressible materials. The advantage of any soft orthotic device is that it may be easily adjusted to changing weight-bearing forces. The disadvantage is that it must be periodically replaced or refurbished. It is particularly effective for arthritic and grossly deformed feet. This material gives the greatest shock absorption however it has the least control of muscles and tendons.

Semirigid Orthotics – the third main type of orthotic device (semirigid) provides for dynamic balance of the foot while walking or participating in sports. This is the ideal material for runners. This orthotic is not a crutch, but an aid to the athlete. Each sport has its own demands and each sport orthotic needs to be constructed appropriately with the sport and the athlete taken into consideration. This functional dynamic orthotic helps guide the foot through proper functions, allowing the muscles and tendons to perform more efficiently. This material gives dynamic control with efficient and moderate control of muscles and tendons. It has greater shock absorption as compared with rigid materials.

Research has shown that back problems frequently can be traced to a foot imbalance. It’s important for your podiatric physician and physical therapist to evaluate you as a whole to provide for appropriate orthotic control for your individual needs.

Importance of how orthotics are made:
It doesn’t end at just getting the right material, how an orthotic is made is just as, if not more, important than the material.

Casting your feet (with plaster) in a non-weight bearing position captures your joints in a 3 dimensional model/mold which is much more accurate than any other technique. The second technique, the use of computer gait scanners only gets a 2 dimensional image of the feet and does not capture the subtalar joint which shows how much your foot is pronating or supinating (3 dimensional gait scanners exist however they are too expensive and most places do not have them yet). The third technique is the use of a foam box which captures the subtalar joint in a semi-weightbearing position. The problem with this technique is that it captures the “abnormal” image of your foot, the position which has caused pain in the first place. With casting, the foot and its joints are placed into an “ideal” neutral position and this is the gold standard technique that we use.

Next, the 3 dimensional ideal molds are sent to a laboratory to produce your custom orthotics. Not all labs are created equal. It is very important for your mold to be sent to a lab with experience in biomechanics and has podiatrists on staff. The lab we use is run by podiatrists and continues to do research to come up with innovative techniques to solve patient concerns and eliminate pain and help prevent injury.

Importance of shoes: There are three common foot types: Flat feet, medium arches, and high arches.

  • For individuals with flat feet (low arches, over pronators), we recommend motion control shoes with straight lasts.
  • For individuals with medium to low arches, we recommend stability shoes with a slight curve last.
  • For individuals with high arches (over supinators), we recommend neutral shoes with curved lasts.

If, for example, you have high arches and you place orthotics into a motion control shoe, you may end up with more pain. It is therefore very important that the right type of shoe is combined with the right type of orthotic for YOUR individual needs. That is why it is important as a runner to have a consultation with your podiatrist to evaluate and recommend the best types and materials for you. Then follow up with your physical therapist to reduce symptoms associated with previous injuries. Together this can solve current symptoms and prevent future injury.

Also consider the soles of your shoes for traction needs of different running surfaces. The heel height is also important. Too much heel height on a running shoe may be good for people with a tight calf or people who have Achilles tendinitis, however if too high, it can cause back, knee or hip pain.

For all foot types, the soles of the shoes should not be too flexible or the orthotics will not function at their maximum capacity. For example, if you place rigid graphite orthotics into ballet flats (which have VERY flexible soles), you may only get 50% function out of your orthotics. However if you place them in a more rigid sole dress or athletic shoe, it will function at its optimum and give you ideal support to help prevent injury.

What about the whole “barefoot running” phenomena?
Barefoot running is an ancient practice widely popularized by one man’s experience with a tribe in Mexico. Products marketed to devotees now reportedly sell more than five times what they did two years ago. “Barefoot running and the use of minimalist footwear are very controversial topics. They are movements within the running community that many are incredibly passionate about,” said Paul Langer, DPM, APMA member, book author, and avid marathoner. While anecdotal evidence and testimonials proliferate on the Internet and in the media about the possible health benefits of barefoot running, research has not yet adequately shed light on the immediate and long term effects of this practice. Dr. Jenkins, a professor at Midwestern University’s Arizona Podiatric Medicine Program, recently compiled extensive research from more than 120 external sources—including Christopher McDougall’s “barefoot bible,” Born to Run. “There has been a lot of focus on the biomechanics of barefoot running, and not as much on the perceived hazards that can cause injury,” he said. Barefoot running may be a possible alternative or training adjunct to running with shoes. Barefoot running has been touted as improving strength and balance, while promoting a more natural running style. However, risks of barefoot running include a lack of protection–which may lead to injuries such as puncture wounds–and increased stress on the lower extremities including causing stress fractures and tendon injury (tendinitis or tendon tears).

Not all foot types are compatible with barefoot running, so it is important to consult a podiatrist to better determine if this type of running is ideal for you.

For more information, or to read about the “Top Five Running Injuries”, click on the link below:

Dr. Noushin Shoaee, DPM
Carmel Valley Foot & Ankle Surgery
4765 Carmel Mountain Road, Suite 104
San Diego, CA 92130