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Tibialis Posterior Tendinosis and Tibialis Posterior Tenosynovitis


Kendrick Alan Whitney

, DPM, Temple University School of Podiatric Medicine

Last full review/revision Dec 2019| Content last modified Dec 2019
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Tibialis posterior tendinosis is wear and tear of the tendon that passes behind and around the inner side of the ankle (called the tibialis posterior tendon). Tibialis posterior tenosynovitis is inflammation of the protective covering around the tendon (called the tendon sheath).

  • The tibialis posterior tendon may become damaged or inflamed.

  • Varying degrees of pain are felt around the ankle.

  • The diagnosis is usually based on symptoms and an examination and sometimes imaging tests.

  • Depending on the disorder, orthoses and surgery or therapy to relieve inflammation can help.

The tibialis posterior tendon helps maintain the normal arch of the foot.

Tibialis posterior tendinosis is usually caused by an excessive ongoing strain caused by a problem with the way the ankle moves. Most often, the person has a low arch, and the foot tends to turn outward when walking, often because the person is overweight. Tendon dysfunction may further contribute to flattening of the arch. The tendon may tear completely, sometimes suddenly in a young person.


In tibialis posterior tendinosis, early on people have occasional pain behind the inner ankle. In time, the pain becomes severe, and swelling occurs. Normal standing and walking become more difficult. Standing on the toes is usually painful and may be impossible if the tendon is completely torn. If the tendon tears completely, the foot may suddenly flatten (called arch collapse) and pain may be felt in the sole.

In tibialis posterior tenosynovitis, pain typically occurs suddenly and the tendon may feel thick and swollen as it winds around the bump on the inside of the ankle (medial malleolus).


  • A doctor's examination

  • Sometimes magnetic resonance imaging (MRI)

Doctors can often base the diagnosis on the person’s symptoms and the results of an examination. However, sometimes MRI Computed tomography (CT) and magnetic resonance imaging (MRI) A doctor can often diagnose a musculoskeletal disorder based on the history and the results of a physical examination. Laboratory tests, imaging tests, or other diagnostic procedures are sometimes... read more Computed tomography (CT) and magnetic resonance imaging (MRI) is necessary to confirm the diagnosis and to see the extent of tendon damage.


  • For tibialis posterior tendinosis, orthoses and braces or surgery

  • For tibialis posterior tenosynovitis, anti-inflammatory therapy

For tibialis posterior tendinosis, devices placed in the shoe (orthoses) and ankle braces worn with supportive shoes or boots are usually sufficient. Complete tears are treated surgically so people can function normally again. Surgery is especially important in young active people with tears that develop suddenly.

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