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Tendinitis and Tenosynovitis


Deepan S. Dalal

, MD, MPH, Brown University

Reviewed/Revised Mar 2022 | Modified Sep 2022

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, nonsteroidal anti-inflammatory drugs (NSAIDs), and sometimes corticosteroid injections.

Tendinopathy usually results from repeated small tears or degenerative changes (sometimes with calcium deposits) 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, popliteus tendon, Achilles tendon ( see Achilles Tendinitis Achilles Tendinitis Achilles tendon injuries include inflammation of the paratenon and partial or complete tears. Achilles tendinitis is very common among running athletes. The calf muscles attach to the calcaneus... read more ), and the abductor pollicis longus and extensor pollicis brevis, which share a common fibrous sheath (the resulting disorder is De Quervain syndrome De Quervain Syndrome De Quervain syndrome is stenosing tenosynovitis of the short extensor tendon (extensor pollicis brevis) and long abductor tendon (abductor pollicis longus) of the thumb within the first extensor... read more ).

Etiology of Tendinitis and Tenosynovitis

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 fluoroquinolone antibiotics may increase the risk of tendinopathy and tendon rupture.

Risk of tendinitis may be increased by certain systemic disorders—most commonly rheumatoid arthritis Rheumatoid Arthritis (RA) Rheumatoid arthritis is a chronic systemic autoimmune disease that primarily involves the joints. Rheumatoid arthritis causes damage mediated by cytokines, chemokines, and metalloproteases.... read more Rheumatoid Arthritis (RA) , systemic sclerosis Systemic Sclerosis Systemic sclerosis is a rare chronic disease of unknown cause characterized by diffuse fibrosis and vascular abnormalities in the skin, joints, and internal organs (especially the esophagus... read more Systemic Sclerosis , gout Gout Gout is a disorder caused by hyperuricemia (serum urate > 6.8 mg/dL [> 0.4 mmol/L]) that results in the precipitation of monosodium urate crystals in and around joints, most often causing recurrent... read more Gout , reactive arthritis Reactive Arthritis Reactive arthritis is an acute spondyloarthropathy that often seems precipitated by an infection, usually genitourinary or gastrointestinal. Common manifestations include asymmetric arthritis... read more Reactive Arthritis , and diabetes Diabetes Mellitus (DM) Diabetes mellitus is impaired insulin secretion and variable degrees of peripheral insulin resistance leading to hyperglycemia. Early symptoms are related to hyperglycemia and include polydipsia... read more or, very rarely, amyloidosis Amyloidosis Amyloidosis is any of a group of disparate conditions characterized by extracellular deposition of insoluble fibrils composed of misaggregated proteins. These proteins may accumulate locally... read more Amyloidosis or markedly elevated blood cholesterol levels. In younger adults, particularly women, disseminated gonococcal infection Gonorrhea Gonorrhea is caused by the bacterium Neisseria gonorrhoeae. It typically infects epithelia of the urethra, cervix, rectum, pharynx, or conjunctivae, causing irritation or pain and purulent... read more Gonorrhea may cause acute migratory tenosynovitis.

Symptoms and Signs of Tendinitis and Tenosynovitis

Affected tendons are usually painful when actively moved or when natural motion is resisted. For example, because the posterior tibial tendon helps invert the foot, passive eversion plus active, resisted inversion causes pain in patients with posterior tibial tendinitis. Occasionally, tendon sheaths become swollen and fluid accumulates, usually when patients have infection, rheumatoid arthritis Rheumatoid Arthritis (RA) Rheumatoid arthritis is a chronic systemic autoimmune disease that primarily involves the joints. Rheumatoid arthritis causes damage mediated by cytokines, chemokines, and metalloproteases.... read more Rheumatoid Arthritis (RA) , or gout Gout Gout is a disorder caused by hyperuricemia (serum urate > 6.8 mg/dL [> 0.4 mmol/L]) that results in the precipitation of monosodium urate crystals in and around joints, most often causing recurrent... read more Gout . Swelling may be visible or only palpable. Along the tendon, palpation elicits localized tenderness of varying severity.

Diagnosis of Tendinitis and Tenosynovitis

  • 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, rule out other disorders, and detect tendon tears and inflammation.

Rotator cuff tendinitis

Rotator cuff tendinitis is the most common cause of shoulder pain. The rotator cuff is composed of four tendons, the supraspinatus, infraspinatus, subscapularis, and teres minor. The supraspinatus tendon is most frequently involved and the subscapularis is second. Active abduction in an arc of 40 to 120° and internal rotation cause pain ( see Rotator Cuff Injury/Subacromial Bursitis Rotator Cuff Injury/Subacromial Bursitis Rotator cuff injury includes tendinitis and partial or complete tears; subacromial bursitis may result from tendinitis. Symptoms are shoulder area pain and, with severe tears, weakness. Diagnosis... read more ). Passive abduction causes less pain, but abduction against resistance can increase pain. Calcium deposits in the tendon just below the acromion are sometimes visible on x-ray. Ultrasonography or MRI may help with further evaluation (eg, if the diagnosis is otherwise unclear) and with treatment decisions (eg, presence of significant tears that might require surgical interventions).

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)

Volar flexor tenosynovitis (digital flexor tendinitis Digital Flexor Tendinitis and Tenosynovitis (Trigger Finger) Digital flexor tendinitis and tenosynovitis are inflammation, sometimes with subsequent fibrosis, of tendons and tendon sheaths of the digits. (See also Overview and Evaluation of Hand Disorders... read more Digital Flexor Tendinitis and Tenosynovitis (Trigger Finger) ) is a common musculoskeletal disorder that is often overlooked. 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. The affected digit may rest in a flexed position, and passive extension elicits pain. 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

Treatment of Tendinitis and Tenosynovitis

  • Rest or immobilization, heat or cold, followed by exercise

  • High-dose nonsteroidal anti-inflammatory drugs (NSAIDs)

  • Sometimes corticosteroid injection

Symptoms are relieved by rest or immobilization (eg, 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 ) for 7 to 10 days. Indomethacin or colchicine may be helpful if gout Treatment Gout is a disorder caused by hyperuricemia (serum urate > 6.8 mg/dL [> 0.4 mmol/L]) that results in the precipitation of monosodium urate crystals in and around joints, most often causing recurrent... read more Treatment is the cause. 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, betamethasone 6 mg/mL, triamcinolone 40 mg/mL, methylprednisolone 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% lidocaine) 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 adjacent joint to reduce the slight risk of tendon rupture. Infrequently, symptoms can worsen for up to 24 hours after the injection.

Pearls & Pitfalls

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

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

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.

Drugs Mentioned In This Article

Drug Name Select Trade
Indocin, Indocin SR, TIVORBEX
Adbeon, Alphatrex, Beta 1 Kit, Beta Derm , Betanate , Betatrex, Beta-Val, BSP 0820, Celestone, Del-Beta , Diprolene, Diprolene AF, Diprosone, Luxiq Foam, Maxivate, ReadySharp Betamethasone, Sernivo, Valisone
Aristocort, Aristocort A, Aristocort Forte, Aristocort HP, Aristo-Pak, Aristospan, Azmacort, Children's Nasacort Allergy 24HR Nasal Spray, Cinalog, Cinolar, Flutex, Hexatrione, Kenalog, Kenalog in Orabase, Kenalog-10, Kenalog-40, Kenalog-80, Nasacort, Nasacort AQ, Oralone, SP Rx 228 , Tac-3 , Triacet , Triamonide , Trianex , Triderm , Triesence, XIPERE, Zilretta
A-Methapred, Depmedalone-40, Depmedalone-80 , Depo-Medrol, Medrol, Medrol Dosepak, Solu-Medrol
7T Lido, Akten , ALOCANE, ANASTIA, AneCream, Anestacon, Aspercreme with Lidocaine, Astero , BenGay, Blue Tube, Blue-Emu, CidalEaze, DermacinRx Lidogel, DermacinRx Lidorex, DERMALID, Ela-Max, GEN7T, Glydo, Gold Bond, LidaMantle, Lidocan, Lidocare, Lidoderm, LidoDose, LidoDose Pediatric, Lidofore, LidoHeal-90, LIDO-K , Lidomar , Lidomark, LidoReal-30, LidoRx, Lidosense 4 , Lidosense 5, Lidosol, Lidosol-50, LIDO-SORB, Lidotral, Lidovix L, LIDOZION, Lidozo, LMX 4, LMX 4 with Tegaderm, LMX 5, LTA, Lydexa, Moxicaine, Numbonex, ReadySharp Lidocaine, RectaSmoothe, RectiCare, Salonpas Lidocaine, Senatec, Solarcaine, SUN BURNT PLUS, Tranzarel, Xyliderm, Xylocaine, Xylocaine Dental, Xylocaine in Dextrose, Xylocaine MPF, Xylocaine Topical, Xylocaine Topical Jelly, Xylocaine Topical Solution, Xylocaine Viscous, Zilactin-L, Zingo, Zionodi, ZTlido
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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