The tendon sheath is a protective layer that surrounds the tendons. It produces a type of oily fluid (synovial fluid) that makes movement smooth and easy. If the tendon gets injured or damaged, it can affect how the tendon sheath works. After tendon injury, the tendon sheath may sometimes start to behave differently; it might not provide the right amount of synovial fluid, or it might stop providing it altogether. 

This makes it difficult for the tendon to move normally – which then causes inflammation of the tendon sheath. This condition is sometimes referred to as tenosynovitis. Although this condition usually occurs after a tendon injury, it can also appear in patients who perform a lot of repetitive motion such as musicians, carpenters or office workers.

How is it treated?

Hand tendons are especially vulnerable to tendon sheath inflammation and common symptoms include joint stiffness, swelling, tenderness, redness and pain. Treatment focuses on reducing the inflammation and pain by resting the affected area and stopping all associated activities. Sometimes, a splint is prescribed to help reduce stress on the tendon. 

Applying heat and ice can help reduce pain and inflammation and in some cases steroid injections can be helpful. In more severe cases of tendon sheath inflammation where it is caused by infection, surgery may be necessary to remove the diseased tendon tissue that is causing the irritation.

How long does it last?

The duration of tendon sheath inflammation will ultimately depend on the cause, as it can occur in conjunction with other conditions like tendonitis, arthritis or infection. 

Adjusting your lifestyle to take account of the condition and following the prescribed treatment pathway is the best way to making a full recovery and avoid future flare-ups. Most patients should make a full recovery between 4-6 weeks.