Auteur: Podiatre Montreal
What is the Achilles tendon?
The Achilles tendon is the largest and most powerful tendon in the body. It is a tendinous structure (connecting muscles to bones) that is composed of a combination of gastrocnemius and soleus muscles that are located at the calf. The tendon connects to the heel bone (the calcaneus) and provides active support (plantar flexion) when the calf muscles tighten. This tendon is essential when walking, running, and jumping. Sports injuries and other types of trauma to the Achilles tendon are common and can be disabling.
What is Achilles Tendonitis?
Tendinitis is an inflammation of a tendon. Thus, Achilles tendinitis is an inflammation of the Achilles tendon. The inflammation could be located at the end of the tendon (near the heel) or even extend upwards and affect the calf muscles. Swelling often occurs and pain is felt when the calf muscles contract. In the most severe cases, pain can even be felt at rest.
In general, Achilles tendonitis usually begins with a vague pain in the back of the leg just above the heel when actively supporting the foot on the ground. Unless activity is stopped, the condition rapidly worsens until any activity requiring active support becomes very painful and almost impossible. Without treatment, this pain can develop into one of two more serious conditions; Achilles tendonitis or ossifying tenositis. These are degenerative changes in the tendon that are very resistant to treatment.
How does the injury occur?
The majority of Achilles tendon injuries are due to overexertion. Other factors that lead to Achilles tendonitis include ill-fitting shoes, lack of stretching exercises before exercising, a short Achilles tendon, direct trauma to the tendon, training errors and deformed heel bone.
There is abundant evidence that people with a tendency to overpronate are more likely to develop Achilles tendonitis.
Excessive pronation puts additional pressure on the tendon, and consequently increases the risk of injury.
How does overpronation cause Achilles tendonitis?
During a normal gait, the thigh bone (femur) and the main leg bone (tibia) rotate in unison as your foot moves inward (pronation) and outward (supination) in a normal manner.
However, when someone has an overpronation, the tibia continues to rotate inward while the femur rotates outward. The counter-rotation of the femur and tibia causes a transverse shearing force in the Achilles tendon.
This occurs because the Achilles tendon is made up of two muscles. One (the gastrocnemius muscle) is attached to the femur while the other (the soleus muscle) is attached to the tibia. This shearing force twists the tendon at its weakest point (the Achilles tendon itself) and causes inflammation.
Since overpronation puts a lot of stress on the Achilles tendon, custom-made functional orthotics to control pronation are an important component of the treatment plan for this type of disorder.
The latest studies on Achilles tendonitis recommend a treatment plan that integrates the following three components:
- treatment of inflammation
- strengthening the muscles that make up the Achilles tendon using eccentric exercises
- control of biomechanics (use of orthotics and appropriate footwear)
Self-treatment of Achilles tendonitis is never recommended because of the risk of permanent damage to the tendon. While you wait to see your doctor, you may get relief by using a heel pad during the day and a night splint at night. A topical pain reliever such as a cryotherapy gel may provide temporary pain relief.
Achilles tendonitis only gets worse over time. If you are experiencing symptoms, make an appointment at our podiatric clinic in Montreal.2021