Tendinitis — also known as tendonitis — is the inflammation of a tendon. It usually happens when a person overuses or injures a tendon during physical activity. It can affect the tendons in the heel, shoulder, elbow, and other joints.

Tendons are cable-like tissues that connect muscles to bones. Although one of their functions is to take some of the strain off the muscles, too much activity can injure them.

Repetitive, overly strenuous exercise can make a tendon inflamed. Also called tendinitis, this inflammation can occur anywhere in the body, including the elbows, ankles, or knees. The affected body part may give the injury its name, such as Achilles tendinitis.

People can manage most cases of tendinitis with rest, ice, and over-the-counter (OTC) pain relievers.

Read more to learn about the different types of tendinitis, its causes, treatment options, and more.

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Tendons are bands of collagen fibers that attach muscles to bones. They are flexible yet tough so that they can stretch and withstand tension.

Both tendons and muscles work together to move joints and limbs. Normally, tendons are resilient and can take some of the stress off of muscles. However, if put under too much strain, they can become inflamed. This is called tendinitis.

Sometimes, doctors misdiagnose tendinitis as tendinosis, a chronic condition that causes the tendons to break down over time.

The damaged or disorganized collagen fibers get hardened and develop scar tissue, which can reduce mobility.

Although it has similar symptoms to tendinitis, tendinosis is considered a more serious condition. It causes long-term tendon damage and is more difficult to treat.

Tendinitis can affect any tendon in the body, but certain types of tendinitis are particularly common.

Achilles tendinitis

The Achilles tendon is a thick band of tissue attaching the heel to the calf muscle. This tendon, which helps a person walk, run, and jump, endures a great deal of stress.

Because of this, Achilles tendinitis is a common sports injury. Additionally, people with rheumatoid arthritis are at a higher risk of Achilles tendinitis.

Supraspinatus tendinitis

In supraspinatus tendinitis, the tendon at the top of the shoulder joint becomes inflamed. This causes pain when moving the arm.

Some people may find it uncomfortable to lie on the affected shoulder at night. If other tendons in the same area are also injured, the person may have a condition called rotator cuff syndrome.

Tennis or golfer’s elbow

Lateral epicondylitis, commonly called tennis elbow, causes pain when a person bends their wrist outwards. This pain may radiate down towards the wrist.

Medial epicondylitis, or golfer’s elbow, causes pain when bending the wrist towards the inside. The pain is more acute when trying to lift against a force.

de Quervain’s stenosing tenosynovitis

This form of tendinitis happens when the sheath surrounding the tendons between the thumb and wrist becomes inflamed. The tendon sheath thickens and swells, making it painful to move the thumb.

Trigger finger or thumb

Trigger finger is a common condition that happens when a finger clicks when straightened. It becomes fixed in a bent position because the tendon sheath in the palm is thickened and inflamed. This restricts the tendon’s movement, so it cannot move smoothly.

Tendinitis of the wrist

Wrist tendinitis can affect anyone who repeatedly performs the same movements with their wrists. It is common in people who do a lot of typing, writing, and sports like tennis.

Although tendinitis symptoms can vary, they usually include:

Both repeated minor injuries and sudden acute injuries can cause tendinitis.

Causes

Most cases of tendinitis are the result of repeated stress or overuse, which could include:

Risk factors

Some people are more likely to get tendinitis than others. Risk factors for tendinitis include:

  • Age: Tendons become stiffer with age, making a person more susceptible to injury.
  • Profession: If a person’s job involves repetitive movements, they are at a higher risk of overuse injuries.
  • Sports: Sports like running, tennis, and golf involve repetitive motions, which can lead to tendinitis.
  • Some health conditions: People with gout, kidney diseases, and rheumatoid arthritis are more likely to develop tendinitis.

If the pain suddenly gets worse, or if it suddenly becomes impossible to move a joint, a person should seek medical attention.

A healthcare professional will ask about symptoms and carry out a physical examination.

They may gently move the affected tendon. This can identify tenderness an a creaking sound, which happens when the tendon sheath becomes thick and inflamed.

For most cases of tendinitis, a doctor will recommend rest, ice, and OTC pain relievers.

Rarely, if symptoms do not improve, a doctor may recommend additional tests. An X-ray can show calcium deposits around the tendon, which may confirm a diagnosis. Other imaging tests such as ultrasound or MRI scans may reveal swelling of the tendon sheath.

Treatment for tendinitis aims to relieve pain and reduce inflammation. Rest, heat and ice, and OTC pain medication are common home treatment options. If these do not improve a person’s symptoms, a doctor may recommend further interventions.

Rest

Tendinitis is an overuse injury. Resting the affected tendon allows the inflammation to reduce. If a sport or specific repetitive motion caused the tendinitis, the person should avoid this activity.

A bandage, splint, or brace may help reduce movement.

Hot and cold therapy

An ice pack can decrease swelling in the affected area. Applying ice for 10–15 minutes once or twice per day can reduce inflammation and pain. A person should always wrap ice in a towel to avoid direct contact with the skin.

Some people also find it useful to alternate heat and ice. They can use hot towels or warm compresses, or take a warm bath.

Ice is normally best for injuries that occurred within the last 48 hours. After this, heat may be a better option.

Pain relievers

There are several medications that can reduce pain, including:

  • OTC medications: Ibuprofen and other nonsteroidal anti-inflammatory drugs can reduce inflammation and tendon pain.
  • Corticosteroid injections: Doctors may recommend these injections around the tendon if inflammation and pain are severe.
  • Physical therapy: Manipulating and massaging the affected area may provide relief, accelerating the healing process.
  • Stretching and exercise: A physical therapist may recommend specific exercises to stretch and strengthen the affected tendon and muscle.

Shock wave therapy or surgery

If tendinitis persists and there are calcium deposits around the tendon, a doctor may suggest extracorporeal shock wave therapy. This involves passing a shock wave through the skin and breaking up the calcium deposits. This can treat tendinitis and improve symptoms.

Tendinitis is a common condition that can be difficult to prevent. While trying to avoid overuse can reduce a person’s chance of getting tendinitis, this can be challenging if they have an occupation that requires repetitive movement.

However, people can lower their chances of getting tendinitis by:

  • warming up before exercising
  • building up an activity’s intensity gradually
  • engaging in sports regularly, rather than only on weekends
  • using proper form when exercising
  • ensuring shoes and gear fit appropriately
  • stopping if a movement causes pain
  • strengthening the surrounding muscles, which can reduce the strain on tendons
  • avoiding repetitive activities where possible
  • taking frequent breaks from repetitive activities

Tendinitis is a common overuse injury that causes inflammation of a tendon. People who have jobs or play sports that involve repetitive motions have an increased risk of these injuries.

Most people can treat the condition with rest, ice, and OTC painkillers. In some cases, a doctor may need to prescribe additional treatments and therapies to support the healing process.