Orthotics for Heel Pain: Why They Don’t Always Work

Heel pain is a common foot problem which may be mild to severe. Although it is not a threat to health, people who suffer from severe heel pain may not be able to work or enjoy life because of this disabling condition. The pain typically develops gradually with no evidence of injury in the affected area. In most cases, the pain is felt under the foot, towards the front part of the heel, although some people experience the pain just behind the heel, where the Achilles tendon attaches to the heel bone.

Heel pain is the most common symptom of a condition called plantar fasciitis. The base of the foot is supported by a thick ligament called the plantar fascia, which lies just beneath the skin and extends from the heel to the front part of the foot. The plantar fascia also supports the bones and tissues, which make up the medial or inner arch of the foot. When this ligament is repeatedly strained and damaged, inflammation and pain ensue, and the condition is known as plantar fasciitis. It commonly manifests as heel pain which usually gets worse in the morning or when one takes a prolonged rest.

What Causes Heel Pain?

There are many factors which can cause heel pain. As mentioned above, this symptom is most commonly associated with plantar fasciitis. Faulty foot mechanics are the most common cause of heel pain and plantar fasciitis. Factors that can cause pain and inflammation of the plantar fascia include:

• Flat feet – when the arch of the foot collapses the foot is noted to look flat, and this stretches the plantar fascia, causing strain and pulling on the insertion of the ligament on the heel.
• Over pronation – when walking, one’s weight usually shifts from the outer to the inner side of the foot, then back to the outer side (normal pronation). When one over pronates the foot, the weight stays in the inner side of the foot, causing excessive strain on the plantar fascia.
• Tight calf muscles – weakness and tightness of the calf muscle (the muscle at the back of the leg) can make it difficult for one to bend the foot towards the shin.
• Achilles tendon rupture
• Wearing incorrect shoes that have soft soles and provide poor arch support
• Nerve problems of the leg and foot
• Fracture of the heel bone
• Obesity (body mass index or BMI of 25 to 30 kg/m2)
• Excessive activity involving running and walking
• Other disease conditions like rheumatoid arthritis, gout, psoriasis, osteomyelitis

What are Foot Orthotics?
Orthotic foot devices (orthoses) are the mainstay of conservative treatment for people with plantar fasciitis. These may consist of custom-made or prefabricated devices that are designed to correct faulty foot mechanics such as the abnormal pronation that causes stress on the plantar fascia. An example of these is a flexible orthotic device with a heel cushion which can disperse some of the pressure placed on one’s weight upon the heel while maintaining support for subsequent propulsion.

Prescription orthotic devices usually provide long-term pain relief by reducing excessive stress on the plantar fascia. Studies have shown that foot orthoses can also reduce the collapse of the medial foot arch and reduce the elongation of the foot when it over pronates.

To create prescription orthoses, a podiatrist or orthopedic surgeon performs a thorough biomechanical examination, which includes checking the range of motion of the foot joints and assessing the forefoot-to-rearfoot link to be able to correct biomechanical abnormalities. This is followed by proper casting of the foot to capture the foot deformity and provide biomechanical support. A more modern, computerized foot analysis may also be done to develop more accurate orthotic devices that reflect the dynamics of one’s gait.

Why Orthotics Don’t Work on All Plantar Fasciitis and Heel Pain
Foot orthotics address only the abnormal biomechanical component of the foot. However, in some patients, there are other factors which may contribute to plantar fasciitis and heel pain which may not be corrected by prescription orthoses. For instance, calf muscle tightness which pulls on the heel can cause stress on the plantar fascia, causing pain which cannot be corrected by orthotic devices alone. Other factors like excessive foot pronation caused by obesity may not be completely corrected by the use of insoles. Heel fracture, nerve entrapment problems, and other diseases conditions like arthritis may need additional treatment, and using orthotic devices alone may lead to poor results.

Another reason why orthotics may not work is that one may not be using the type of orthoses suitable for one’s physical and functional characteristics. There are three types of foot orthotics - rigid, semi-rigid, and soft orthoses. Rigid orthotics are made of firm material such as plastic and they must fit snugly to control the feet’s function and to correct anatomical abnormalities which may be causing the pain.

Semi-rigid orthotics are made of both soft and hard materials which provide layered support and allow for balance while moving rapidly or playing sports. They are commonly used by athletes.

Soft orthotics are typically available in the form of shoe inserts designed to reduce pressure and shock, making walking more comfortable. These are useful for people who spend long hours standing, diabetics or obese individuals, and those who suffer from arthritis.

Management of Plantar Fasciitis
To be able to provide adequate treatment for heel pain secondary to plantar fasciitis, a clear diagnosis must be made and the precipitating factors must be identified.

Diagnosis
A clinician typically assesses a patient with heel pain by doing a thorough medical history and physical examination with emphasis on the inferior heel and plantar fascia. Findings of a pronated foot architecture and localized swelling of the heel indicate plantar fasciitis. Additional tests to assess function of the foot may be done, such as range of motion tests, tarsal tunnel syndrome test, windless test, and examination of the longitudinal arch angle. Radiographic examinations are not necessary to diagnose plantar fasciitis although they may be useful for showing evidence of architectural abnormalities in the foot, as well as heel spurs, and for ruling out other conditions such as fractures or arthritis, if the clinician is in doubt.

In addition, other forms of assessment may be done to evaluate contributing factors that bring about the patient’s symptoms, such as measurement of BMI, tests for diabetes, arthritis, gout, nerve disorders, calf muscle weakness, heel fracture, and others. These factors must be properly addressed to reduce the risk of heel pain and to allow other forms of treatment to work.

Treatment
Heel pain may range from mild to severe, and foot experts use a tiered management plan in choosing treatment options for plantar fasciitis based on clinical research.

Initial forms of therapy typically involve patient-directed treatment options like:

• Rest, limiting activities
• Stretching exercises for the calf muscles
• Avoiding flat shoes and walking barefoot
• Weight loss
• Oral anti-inflammatory drugs
• Using prefabricated over-the-counter arch support or heel cups
• Padding and strapping
• Home physical therapy
• Wearing good quality shoes

If results with these treatments are unsatisfactory after 6 weeks, clinicians may prescribe:

• Night splints – usually prescribed for patients who experience heel pain for more than 6 months
• Custom orthotic devices - used for a few months to provide short-term reduction in pain and improvement of function.
• Corticosteroid injections
• Prescribed physical therapy
If these treatments or combinations of therapy still fail to relieve the patient’s symptoms after 6 months, surgery may be considered to correct anatomical abnormalities. Surgical procedures may involve removal of bone spurs, plantar fascia release, or calf muscle lengthening among others.

In addition, investigation on other causes of heel pain may be initiated, such as evaluating for arthritis, nerve problems, or tumors. Management of these problems may help relieve heel pain which may be an accompanying symptom of the main pathology.

References:
Barrett, S. and O’Malley, R. Plantar Fasciitis and Other Causes of Heel Pain. AAFP. Am Fam Physician. 1999 Apr 15; 59(8):2200-2206.

The Diagnosis and Treatment of Heel Pain. ACFAS. http://www.acfas.org/uploadedFiles/Healthcare_Community/Education_and_Publications/Clinical_Practice_Guidelines/HeelPainCPG.pdf

McPoil, T., Martin, R., Cornwall, M., et al. Heel Pain—Plantar Fasciitis: Clinical Practice Guidelines Linked to the International Classification of Function, Disability, and Health from the Orthopaedic Section of the American Physical Therapy Association. J Orthop Sports Phys Ther. 2008:38(4):A1-A18. doi:10.2519/jospt.2008.030

What are Orthotic Devices? WiseGeek. http://www.wisegeek.com/what-are-orthotic-devices.htm

Start your heel pain treatment today.