Achilles Tenosynovitis

Chronic Achilles tendinitis can lead to Achilles tenosynovitis if left untreated.

Each tendon in your body has a protective sheath that helps the tendon stay lubricated (with synovial fluid) and glide smoothly between other soft tissue in the area. Injury to this 'sheath' means production of this synovial fluid is compromised or the fluid leaks outside the sheath. Either way, sheath damage often results in inadequate tendon lubrication. If you are suffering from an injury of this type to the Achilles tendon, the term is known as Tenosynovitis (or paratenonitis / peritendinitis). This basically means inflammation and degeneration of the tendon's outer layer or sheath.

It is possible to suffer from Achilles tenosynovitis alone but usually it occurs alongside achilles tendinosis - a chronic degeneration of the achilles tendon. In cases of tendonosis, the tendon swells up so much that it often tears the sheath. As your body tries to heal the tendon sheath, scar tissue forms inside the sheath - creating attachments from the tendon to the paratenon (paratenon=sheath). This scar tissue limits the gliding movement of the tendon in the sheath, reducing range of motion and causing sharp pains, tenderness, redness and swelling.

Symptoms of Achilles Tenosynovitis

Achilles Tenosynovitis

The pain you feel when you are suffering from Achilles paratenonitis (tenosynovitis) is usually a result of the inflammation in the tendon as well as the scar tissue that has built up between the tendon and the paratenon. When you move your Achilles tendon the scar tissue stops the tendon from gliding smoothly through the shealth. As the tendon moves, more tearing of the tissue occurs and more scar tissue begins to form as these tears heal. It's a cycle that needs to be broken by getting rid of the scar tissue. With Achilles tenosynovitis you may also experience:

  • Difficulty moving and flexing your ankle.
  • Swelling at the back of the ankle, around the Achilles tendon.
  • Pain may subside when the Achilles tendon is allowed to rest.
  • The Achilles tendon is tender and warm to the touch.
  • If you have been suffering from tenosynovitis for awhile, you may have a lump formation due to scar tissue building up on the tendon.
  • A fever may indicate that the tendon and/or sheath is infected. You should see a doctor immediately if you are experiencing a fever to treat the infection appropriately.

Causes of Achilles Tenosynovitis

In most instances, Achilles paratenonitis it is a result of repetitive strain or over-use that occurs over a period of time. It is common among runners and triathletes and is usually caused by improper training or weak tissue, such as:

  • Improper stretching before and after running and jumping exercises.
  • Poor or misfitted foot wear.
  • An inflexible Achilles tendon (i.e. tendon with scar tissue from previous injury or wear and tear).
  • An increase in training, training on uneven terrain or a change in terrain (i.e. hills).
  • Weak or inflexible calf muscles (gastrocnemius or soleus).

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During your recovery, you will probably have to modify and/or eliminate any activities that cause pain or discomfort at the location of your soft tissue injury until the pain and inflammation settle. Always consult your doctor and/or Physical Therapist before using any of our outstanding products, to make sure they are right for you and your condition.


Please be aware that this information is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider before using any of our outstanding products to make sure they're right for you and your condition or if you have any questions regarding a medical condition. Always see your doctor for a proper diagnosis as there are often many injuries and conditions (some very serious) that could be the cause of your pain.

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