Before we dive into achilles tendonitis treatment options, it’s important to identify what type of achilles injury you have. There are various terms used to label an achilles injury, such as; achilles tendonitis, achilles tendinosis, achilles tendinopathy and achilles paratenonitis. For clarity and highlighting how an accurate diagnosis is important for best treatment plans, a brief outline for each of these is below;
Achilles tendonitis refers to when the achilles tendon is acutely overloaded and inflamed. The ‘itis’ in tendonitis refers to inflammation. This sort of condition is often called a ‘reactive tendon’; the tendon swells and signals pain as a protective mechanism so you don’t create structural damage (as seen in tendinosis). This is an acute overload of the achilles tendon and it will feel uniformly thicker along the entire tendon (fusiform swelling) and more sensitive to squeeze than the non-symptomatic side. Symptoms are usually high grade and the tendon typically doesn’t ‘warm-up’ and improve as you exercise. Achilles tendonitis treatment is best implemented early with rest and offloading.
Achilles tendinosis refers to when the achilles tendon has been chronically overloaded over a period of months. The ‘osis’ in tendinosis refers to a change in tendon structure, often as focal areas of ‘scar tissue’ or less dense or aligned collagen fibres that make up the tendon structure, and thus this condition is often called a ‘degenerative tendon’. This can be seen on imaging and in some cases, you can feel lumps and bumps when running your fingers along the length of the achilles tendon. Symptoms are usually lower grade than achilles tendonitis and typically you will feel morning stiffness that eases off as your tendon warms up. Some people can function relatively well with an achilles tendinosis and can still participate in their sport but may need a little longer to warm up before higher intensity exercise for the tendon to feel pain free. Typically, the tendon will be sorer the next morning after more intense exercise. Achilles tendinosis treatment usually always involves heavy slow resistance training in the form of calf raise exercises.
Achilles tendinopathy is an umbrella term that can encompass both tendinitis and tendinosis. It is also possible (and common) to have co-existing diagnoses; where someone has a degenerative tendon with low grade chronic symptoms, but they turn it into a reactive tendon and re-introduce higher grade symptoms and swelling after an increase in activity. This is also known as an ‘acute-on-chronic’ tendinopathy.
As opposed to tendinitis and tendinosis, which are conditions of the tendon itself, achilles paratenonitis is an acute injury involving inflammation and swelling of the lining of the achilles tendon, also known as the tendon sheath. Typically, there will be high grade pain and significant swelling around the tendon, with a key difference to tendinitis being the presence of crepitus. Crepitus is a creaking or crunching like sensation that can be felt when pointing the foot up and down. The term achilles peritendinitis is also used interchangeably with paratneonitis to describe this condition.
We also need to consider other diagnoses around the achilles tendon, which include; insertional achilles tendinopathy, retrocalcaneal bursitis, subcutaneous calcaneal bursitis, Kager’s fat pad inflammation and plantaris-related achilles pain.