The Achilles tendon, the largest and single strongest tendon in the body, connects the heel bone to the muscles in the back of your leg and thigh. The primary function of the Achilles tendon is to transmit the power of these muscles to the foot enabling walking and running.
Part of the reason that this is now called tendinopathy and not “tendinitis” is because of the ongoing debate as to what this condition entails. It’s a bit more complex than you might think! We no longer believe the condition involves inflammation which is why we’ve changed the “itis” at the end (a word ending in “itis” usually suggests inflammation). We now know that instead of inflammation the tendon has a reactive response which thickens and stiffens it and acts as a “stress shield” to reduce load.
Why do Achilles tendon injuries occur?
Achilles tendon injuries can occur especially when the tendon is subjected to strong forces such as in velocity sports: running, soccer, basketball, tennis, and baseball. Additionally, aging, and the Achilles tendons poor blood supply also increases your chance of injury. The area of the tendon with the poorest blood supply is the area (2 to 6 cm) just above its insertion into the heel bone. The blood flow to this area decreases as you get older. This means, older active individuals are more vulnerable to this injury.
Symptoms may include:
. Pain in the back of the heel that can be a shooting pain, burning pain or even an intense piercing pain.
. Swelling, tenderness and warmth over the Achilles tendon especially at the insertion of the tendon to the calcaneous, which may even extend into the muscle of the calf.
. Difficulty walking – sometimes the pain makes walking impossible.
. Pain that is aggravated by activities that repeatedly stress the tendon, causing inflammation or pain that occurs in the first few steps of the morning or after sitting down for extended periods of time, which gets better with mild activity.
Some of the causes of Achilles tendonitis / tendinosis include:
Overuse injury – this occurs when the Achilles tendon is stressed until it develops small tears. Runners seem to be the most susceptible. People who play sports that involve jumping, such as basketball, are also at increased risk.
Arthritis – Achilles tendonitis can be a part of generalised inflammatory arthritis, such as ankylosing spondylitis or psoriatic arthritis. In these conditions both tendons can be affected.
Foot problems – some people with over pronated feet (Flat Feet) or feet that turn inward while walking are prone to Achilles tendonitis. The flattened arch pulls on calf muscles and keeps the Achilles tendon under tight strain. This constant mechanical stress on the heel and tendon can cause inflammation, pain and swelling of the tendon. Being overweight can make the problem worse.
Footwear – wearing shoes with minimal support while walking or running can increase the risk, as can wearing high heels.
Overweight and obesity – being overweight places more strain on many parts of the body, including the Achilles tendon.