Achilles Tendinosis

​What is Achilles tendinosis?

When the Achilles tendon degenerates and become inflamed, the condition is called Achilles tendinosis.  The tendon can swell and may cause pain. This condition is common in athletes, runners and patients who have calf tightness. Achilles tendinosis may occur in the middle of the tendon. This is known as midsubstance Achilles tendinosis. It may also occur at the point where the tendon connects to the heel bone. This is known as insertional Achilles tendinosis.

What are the symptoms of Achilles tendinosis?

Many changes can be seen when the Achilles tendon becomes inflamed. Patients have pain and/or tightness in the tendon behind the ankle. Most of the time there is no trauma or injury, but rather a slow progression of pain. Patients may have difficulty climbing stairs or running. Patients may also have pain after sitting for long periods or after sleeping. Many patients will notice a bump either in the tendon (midsubstance Achilles tendinosis) or right behind the heel bone (insertional Achilles tendinosis). Some may also get irritation from shoes rubbing against the bump and feel better when wearing backless shoes. Patients also commonly have less pain while wearing a shoe with a slight heel versus shoes that are flat.

What causes Achilles tendinosis?

Achilles and calf tightness is a common cause of Achilles tendinosis. In addition, insertional Achilles tendinosis is often associated with a heel bone spur. This spur may rub against the Achilles tendon and lead to breakdown and small tears. It is similar to a rope being rubbed against a sharp rock. This is also known as Haglund’s Syndrome. Pain and swelling occur as the cumulative effects of chronic wear and tear on the tendon.  

How is Achilles tendinosis diagnosed?

A thorough history is taken and an examination is performed. Patients will usually have pain right on the tendon or at the back of the heel. They may also have swelling and thickening of the tendon. X-rays may be taken to see if there are any bone spurs.  An MRI or ultrasound may also be performed to further evaluate how much of the tendon is affected and to look for any tears.

What are treatment options?

Treatment depends on the length and severity of the symptoms. Many patients improve without surgery. Rest and oral medications may help reduce the swelling and pain. Heel cups can improve pain by taking some of the stress off of the Achilles tendon when walking. A walking boot or other brace may be recommended.
Often formal physical therapy is recommended to work on stretching and improve mobility within the calf muscle.  Other treatments may include ultrasound, massage, shockwave therapy and topical nitroglycerin patches. Recently, platelet rich plasma has been discussed as a treatment for Achilles tendinosis. This involves taking one’s own blood and isolating growth factors that are involved in healing. This serum is then injected into the inflamed tendon.
In some cases, surgery may be required.  The specifics of the surgery depend upon the location and extent of the tendinosis.

Frequently Asked Questions

If I am treated without surgery for Achilles tendinosis will it come back?
While most patients will achieve lasting relief after treatment for Achilles tendinosis, symptoms may return. The risk decreases if the patient continues to do routine stretching even after the symptoms resolve. However, athletes and runners in particular are at a slightly higher risk for this condition because of the high demands on the Achilles. These patients should pay close attention to stretching and shoewear to prevent chronic recurrence. 
What are the outcomes for those who have surgery for Achilles tendinosis?
Surgery can predictably return patients to activity. Success rates have been reported between 80 and 90 percent, which means that eight to nine out of 10 people improve with surgery. Some of the variability depends on the amount of tendon that is diseased at the time of surgery. 
Patients improve with both conservative and operative management of Achilles tendinosis. Physical therapy has been shown to help most patients with this condition and should be tried before surgical management is proposed. 


Achilles Tendinosis Surgery
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