Tendinitis is inflammation of a tendon, often developing after degeneration (tendinopathy). Tenosynovitis is tendinitis with inflammation of the tendon sheath lining. Symptoms usually include pain with motion and tenderness with palpation. Chronic deterioration or inflammation of the tendon or tendon sheath can cause scars that restrict motion. Diagnosis is clinical, sometimes supplemented with imaging. Treatment includes rest, NSAIDs, and sometimes corticosteroid injections.

Tendinopathy usually results from repeated small tears or degenerative changes (sometimes with Ca deposit) that occur over years in the tendon.

Tendinitis and tenosynovitis most commonly affect tendons associated with the shoulder (rotator cuff), the tendon of the long head of the biceps muscle (bicipital tendon), flexor carpi radialis or ulnaris, flexor digitorum (for infectious flexor tenosynovitis, see Hand Disorders: Infectious Flexor Tenosynovitis), popliteus tendon, Achilles tendon (see Sports Injury: Achilles Tendinitis), and the abductor pollicis longus and extensor pollicis brevis, which share a common fibrous sheath (the resulting disorder is de Quervain syndrome—see Hand Disorders: De Quervain Syndrome).

Etiology

The cause of tendinitis is often unknown. It usually occurs in people who are middle-aged or older as the vascularity of tendons decreases; repetitive microtrauma may contribute. Repeated or extreme trauma (short of rupture), strain, and excessive or unaccustomed exercise probably also contribute. Some quinolone antibiotics may increase the risk of tendinopathy and tendon rupture.

Risk of tendinitis may be increased by certain systemic disorders—most commonly RA, systemic sclerosis, gout, reactive arthritis, and diabetes or, very rarely, amyloidosis or markedly elevated blood cholesterol levels. In younger adults, particularly women, disseminated gonococcal infection may cause acute migratory tenosynovitis.

Symptoms and Signs

Affected tendons are usually painful when moved. Occasionally, tendon sheaths become swollen and fluid accumulates, usually when patients have infection, RA, or gout. Swelling may be visible or only palpable. Along the tendon, palpation elicits localized tenderness of varying severity.

In systemic sclerosis, the tendon sheath may remain dry, but movement of the tendon in its sheath causes friction, which can be felt, or heard with a stethoscope.

Diagnosis

• Clinical evaluation
• Sometimes imaging

Usually, the diagnosis can be based on symptoms and physical examination, including palpation or specific maneuvers to assess pain. MRI or ultrasonography may be done to confirm the diagnosis or rule out other disorders. MRI can detect tendon tears and inflammation (as can ultrasonography).

• Rotator cuff tendinitis: This disorder is the most common cause of shoulder pain. Active abduction in an arc of 40 to 120° and internal rotation cause pain (see Sports Injury: Rotator Cuff Injury). Passive abduction causes less pain, but abduction against resistance can increase pain. Ca deposits in the tendon just below the acromion are sometimes visible on x-ray. Ultrasonography or MRI may help with further evaluation and with treatment decisions.
• Bicipital tendinitis: Pain in the biceps tendon is aggravated by shoulder flexion or resisted supination of the forearm. Examiners can elicit tenderness proximally over the bicipital groove of the humerus by rolling (flipping) the bicipital tendon under their thumb.
• Volar flexor tenosynovitis (digital flexor tendinitis): This common musculoskeletal disorder is often overlooked (see Hand Disorders: Digital Flexor Tendinitis and Tenosynovitis (Trigger Finger)). Pain occurs in the palm on the volar aspect of the thumb or other digits and may radiate distally. Palpation of the tendon and sheath elicits tenderness; swelling and sometimes a nodule are present. In later stages, the digit may lock when it is flexed, and forceful extension may cause a sudden release with a snap (trigger finger).
• Gluteus medius tendinitis: Patients with trochanteric bursitis almost always have gluteus medius tendinitis. In patients with trochanteric bursitis, palpation over the lateral prominence of the greater trochanter elicits tenderness. Patients often have a history of chronic pressure on the joint, trauma, a change in gait (eg, due to osteoarthritis, stroke, or leg-length discrepancy), or inflammation at this site (eg, in RA).

Treatment

• Rest or immobilization, heat or cold, followed by exercise
• High-dose NSAIDs
• Sometimes corticosteroid injection

Symptoms are relieved by rest or immobilization (splint or sling) of the tendon, application of heat (usually for chronic inflammation) or cold (usually for acute inflammation), and high-dose NSAIDs (see Table 2: Joint Disorders: NSAID Treatment of Rheumatoid Arthritis) for 7 to 10 days. IndomethacinSome Trade Names
INDOCIN
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or colchicineSome Trade Names
No US trade name
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may be helpful if gout is the cause (see Crystal-Induced Arthritides: Gout). After inflammation is controlled, exercises that gradually increase range of motion should be done several times a day, especially for the shoulder, which can develop contractures rapidly.

Injecting a sustained-release corticosteroid (eg, betamethasoneSome Trade Names
CELESTONE
DIPROLENE
LUXIQ
MAXIVATE
VALISONE
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6 mg/mL, triamcinoloneSome Trade Names
ARISTOCORT
KENACORT
KENALOG
NASACORT
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40 mg/mL, methylprednisoloneSome Trade Names
MEDROL
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20 to 40 mg/mL) in the tendon sheath may help; injection is usually indicated if pain is severe or if the problem has been chronic. Injection volume may range from 0.3 mL to 1 mL, depending on the site. An injection through the same needle of an equal or double volume of local anesthetic (eg, 1 to 2% lidocaineSome Trade Names
XYLOCAINE
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) confirms the diagnosis if pain is relieved immediately. Clinicians should be careful not to inject the tendon (which can be recognized by marked resistance to injection); doing so may weaken it, increasing risk of rupture. Patients are advised to rest the injected joint to reduce the slight risk of rupture. Infrequently, symptoms can worsen for up to 24 h after the injection.

Repeat injections and symptomatic treatment may be required. Rarely, for persistent cases, particularly rotator cuff tendinitis, surgical exploration with removal of Ca deposits or tendon repair, followed by graded physical therapy, is needed. Occasionally, patients require surgery to release scars that limit function or tenosynovectomy to relieve chronic inflammation.

Pearls & Pitfalls Do not inject corticosteroids into a tendon; doing so will weaken it, increasing risk of rupture.

Key Points

• Tendinitis and tenosynovitis, unlike tendinopathy (tendon degeneration), involve inflammation.
• Pain, tenderness, and swelling tend to be maximal along the tendon's course.
• Diagnose most cases by examination, including tendon-specific maneuvers, sometimes confirming the diagnosis with MRI or ultrasonography.
• Treat with rest, heat or cold, high-dose NSAIDs, and sometimes corticosteroid injection.

Last full review/revision February 2013 by Joseph J. Biundo, MD

Content last modified March 2013