Tenosynovitis is the inflammation of a tendon and the lining of the protective tissue that encloses it. It commonly affects the hand, wrist, and foot, causing discomfort, swelling, and pain.

Tendons are tough tissue bands that connect muscles to bones.

A membrane-like structure called a tendon sheath or synovial sheath surrounds most tendons, separating them from the surrounding tissues.

Any injury or damage to the tendon also affects its covering, leading to tenosynovitis.

This article explores tenosynovitis in more detail, including its symptoms, causes, and risk factors. It also looks at how to diagnose, treat, and prevent this condition.

A person holding their wrist with their other hand rested on a deskShare on Pinterest
marchmeena29/Getty Images

Tenosynovitis is the inflammation of the tendon and the tendon sheath surrounding it.

Tendon sheaths provide a slippery surface that keeps the tendons lubricated, allowing them to glide easily within the sheath.

Infection, irritation, or damage to the tendon also causes inflammation and irritation to the tendon sheath.

Tenosynovitis can occur in any tendon that has a sheath surrounding it. However, doctors commonly see it in the body parts where the tendons are long across the joints, including the:

  • hands
  • wrists
  • feet
  • ankles

Tenosynovitis vs tendinitis

Tenosynovitis is the inflammation of both the tendon and the tendon sheath, whereas tendinitis is the inflammation of a tendon.

The diagnosis and treatment of these two conditions tend to overlap.

The symptoms vary depending on the cause and extent of the injury, but they generally include:

  • swelling
  • pain
  • difficulty moving the affected joint

Stenosing tenosynovitis is a type of tenosynovitis that doctors commonly call trigger finger.

This inflammation makes it harder for the tendon to glide through the sheath, causing “catching” and “locking” joints.

When the tenosynovitis progresses, a person may present with visible contracture deformities — a joint abnormality where a person cannot straighten one or more fingers — and an inability to relax the tendons.

The affected tendon sheaths may become swollen as fluid accumulates, and this swelling can be palpable or even visible. This symptom is common in those with:

Nodules and deposits can also accompany the inflammation experienced with RA.

Doctors do not always know the exact cause of tenosynovitis.

It occurs more frequently in middle-aged or older adults because the tendons weaken. The blood supply in the tendons also decreases as a person ages.

Tenosynovitis can result from different factors, and experts divide into two main types: infectious and noninfectious.

The noninfectious types can occur due to:

  • autoimmune factors
  • overuse
  • systemic diseases

In some cases, they are idiopathic, meaning they have no known cause.


Bacterial infections can reach the sheath from infected wounds. Emergency surgery may be necessary if a person does not prompt and effective treatment.

Common bacterial infections may include Staphylococcus aureus and methicillin-resistant S. aureus. These bacteria may spread from local or distant infections in other body areas.

People should consult a doctor to determine the possible cause.

Autoimmune conditions

These conditions occur when the immune system mistakenly attacks the body’s tissues. This may damage the synovium and lead to tenosynovitis.

Up to 87% of people with RA show features of tenosynovitis on MRI scans. More than half have a significant risk of tenosynovitis, which affects several tendons.


Frequent, prolonged, and repetitive movements can irritate the tendons and cause inflammation of the synovial sheath. Extreme or repeated trauma and strain can also contribute to injury.

Unfamiliar movements involving the affected tendon may also lead to inflammation. Examples include walking or running long distances without prior training or wearing new shoes.

Certain activities also increase a person’s risk of tenosynovitis:

  • working at a computer for prolonged periods
  • playing musical instruments
  • prolonged typing on smartphones
  • lifting and carrying a child regularly

Systemic diseases

Other inflammatory and systemic conditions can also damage the synovial sheath, including:

About 10–20% of people with diabetes also develop tenosynovitis.


Some cases are idiopathic, which means that they have no identified cause.

Certain fluoroquinolone antibiotics may also increase a person’s risk of tenosynovitis.

Other risk factors associated with tenosynovitis include:

  • middle or older age
  • being female
  • having or having had similar conditions, such as neuropathy and stenosing tendinopathy
  • having diabetes
  • pregnancy
  • lactation

The condition may be more likely to affect the dominant hand.

The doctor will conduct a detailed medical history to learn about the possible causes of the condition and examine the affected area.

The doctor may request further tests if they suspect another condition to be causing the symptoms. These may include blood tests to check for infections or imaging tests such as an ultrasound or X-ray for a more in-depth assessment.

Doctors will usually recommend conservative treatment initially. If this proves effective, it will mean that a person does not need to undergo surgery, which carries risks.

The treatment options for tenosynovitis include:

  • resting the affected area
  • making changes in the workplace, such as the use of ergonomics
  • wearing plaster casts, splints, or braces
  • physical therapy, which may involve improving range of motion through physical activity and performing stretching exercises
  • taking nonsteroidal anti-inflammatory medications
  • a steroid injection, which a doctor will deliver alongside a local anesthetic

If a bacterial infection causes the condition, the treatment will involve taking antibiotics.

In cases where the condition progresses after 3–6 months, doctors may consider surgery. Surgical procedures may involve cutting or removing tissue to relieve pressure and give the tendon more room to move.

Learn more about tendon repair.

People can take steps to help prevent tenosynovitis. These include:

  • warming up sufficiently before playing sports or performing the exercise
  • treating wounds hygienically to avoid infections
  • ensuring that the workstation is ergonomically designed
  • having regular rest periods when carrying out repetitive, high-strain tasks
  • participating in muscle-strengthening sessions with a physical therapist

Tenosynovitis affects 2–3 in every 100 people. After sufficient rest and immobilization, most symptoms will go away independently within a few weeks.

If tenosynovitis is due to overuse and repetitive movement, the condition may return if a person does not stop the activity.

Tenosynovitis is a common condition that causes inflammation of the tendon and the synovial sheath that wraps around it.

It often leads to pain, discomfort, stiffness, and limited movement in the wrists, hands, ankles, and feet.

Most symptoms resolve with enough rest, immobilization, and medication. However, some cases may require more invasive management, such as steroid injections or surgery.