Whether it is taking a daily stroll, or playing a sport professionally, physical activity places enormous stress and strain on your bones, joints, muscles and tendons. For decades foot specialists and other health practitioners have been prescribing orthotics to both alleviate pain and correct the condition; but how do they work? Is there a difference between the off-the-shelf inserts at the drug store versus custom-made?
The term orthotics is defined as a specialty within the medical field concerned with the design, manufacture, and applications of orthosis. Orthosis (plural: orthoses) is an orthopedic device that supports or corrects the function of a limb or torso. Therefore orthosis, also known as braces, have applications all over the body. A lower limb orthosis is an external device applied to improve function by controlling motion, providing support through stabilizing walking-patterns, reducing pain through transferring load to another area, correcting deformities due to excess flexibility, and preventing progression of fixed deformities. Foot orthoses, or more commonly known as orthotics, are specially fitted inserts for the insole or footbed. They are designed to align the foot and ankle in the most anatomically efficient position, working to correct an individual’s specific foot imbalance.
Is there such a thing as a perfect foot? Chances are if you are experiencing the following symptoms, you suffer from poor foot biomechanics:
- Localized foot pain
- Bunions, hammer toes
- Arch/heel pain
- Leg/knee pain
- Hip pain
- Back pain
- Neck Pain
The way you walk effects your posture, therefore a dysfunction anywhere in your body from your feet up can manifest as high as into your neck. Many injuries stem from a biomechanical gait abnormality that can be treated with custom orthotics. Some of these common injuries are:
Achilles tendonitis is an inflammation of the common tendon of the gastrocnemius and soleus muscles that make up the calf. Patients that have a shortened or tight achilles tendon (known as equinus deformity) and/or routinely run up-hill, are candidates for this disorder. There is also the theory that over-pronation may reduce the blood supply to the area. Over-pronation promotes a twisting movement of the tendon, which essentially causes a wringing effect of the tendon-supplying artery, therefore causing an insufficiency of arterial blood supply to the area.
Iliotibial Band Syndrome
Iliotibial Band Syndrome is an inflammatory reaction of the muscle on the outside of the thigh, which is composed from a thick extension of the tensor fascia latae muscle. The band slides over the the greater trochanter or hip bone, and inflammation can often occur at this site. Over-pronation of the foot is accompanied by internal rotation of the lower limb, which increases the friction between the band and the bony protuberance of the hip. This injury is quite common in runners, especially those who run the same route often, or downhill.
Plantar fasciitis is an inflammatory condition occurring most often at the inner portion of the heel or calcaneus, where the plantar fascia attaches to the medial tuberosity of the calcaneus. Over-pronation results in a constant tugging of the aforementioned attachment site, which leads to inflammation. Symptoms usually wax and wane, as when the patient rests and is no longer weight-bearing, scar tissue begins to repair the site of injury. When the patient gets back on their feet and begins activity, the scar tissue is torn, resulting in acute pain. This explains why patients with this injury typically experience the most pain when they get out of bed, or stand after a period of sitting. To learn more about treatment of plantar fasciitis, please read our blog on physiotherapy treatment for plantar fasciitis.
Morton’s neuroma is a thickening of the tissue that surrounds the intermetatarsal plantar nerve leading to the toes. Pain results when the nerve becomes squeezed and irritated, often due to wearing shoes with too narrow of a toe-box. Classically symptoms will present as a “pins and needles” sensation that spreads through the fourth and fifth toes. Irritation of the plantar nerve can occur by one or more factors:
- Abnormal foot function or foot mechanics: primarily excessive pronation that causes strain on the nerve.
- Improper footwear: constricting, narrow, poor-fitting shoes with a tight or pointed toe box tend to compress the end of the foot, leading to excessive pressure in the area of the nerve. High-heeled shoes are a likely culprit.
- Previous trauma to the foot: High-impact activities that bring repetitive trauma to the foot (running, aerobics, etc.) can lead to a greater chance of developing a neuroma.
Shin splits is an overuse injury related to either the muscles in the front or back of the shin – Tibialis anterior or posterior. Both of these muscles are involved in slowing down pronation during the stance phase of gait. Tibialis anterior functions early in the stance while Tibialis posterior functions a little later. Over-pronation or pronating too rapidly, leads to either or both of these muscles working harder than normal. As a result, fatigue sets in, and there is an inefficient force production. This can lead to micro-tearing of the soft tissue and a subsequent inflammatory reaction. The muscle is wrapped in a fascial covering, and the swelling that occurs is that constricted by the finite space, leading to much pain and, in severe cases, insufficient blood supply to the muscles.
Runner’s Knee is a general term referring to pain around the front of a runner’s knee. If the pain is in the front and medial location, the source of the problem may be over-pronation. The internal rotation of the shin-bone/tibia associated with over-pronation, can cause the knee to fall into a functional valgus (knock-need) orientation during the stance phase of gait. This in turn will place extra stress on the ligaments on the medial aspect of the knee.
Sacroilliac sydrome is a painful inflammatory condition of the sacroiliac joints. Pain is generally experienced in the buttock and thigh regions, and aggravated by sitting for long periods. Often due to trauma or repetitive lifting from the ground, there is some evidence to suggest that a chronic irritation from abnormal foot mechanics is also a possible cause. As already mentioned, when the foot over-pronates, there is a propensity for internal rotation of the lower limb. Due to the anatomy of the hip joint, this internal rotation translates into an extension of the pelvis. If the mechanics of the feet are not symmetrical, then conflicting rotations may occur at the two sacroiliac joints. This mechanism is suspected to cause chronic irritation of these joints leading to the inflammation.
Custom orthotics work on your feet much like glasses work on your eyes – they reduce stress and strain on your body by bringing your feet back into proper alignment. There is a misconception that the orthotic can reduce muscle tone; rather, they help position your foot to enable usage of the right muscles at the appropriate time. Fatigue is thus minimized by promoting more efficient muscle usage.
The longer you wear your custom orthotics, the greater the benefit. Since they work to realign the structure of your foot, you may feel pressure in some areas as your body adapts. For this reason orthotics should be worn in one-to-two hour intervals, and slowly extend the wear time over a period of one or two weeks.
Still unsure if orthotics are right for you? Your trusted chiropractor or physiotherapist can assess whether you are a good candidate, and explain how orthotics may benefit you. Most extended health care plans cover them, so you can benefit physically without having to pay out of pocket. Contact us today for more information.
Written By: Dr. Melissa Cutler, DC