Tendonitis

Tendons transmit the forces of muscle to the skeleton. As such, they are subjected to repeated mechanical loads, which are felt to be a major causative factor in the development of tendinopathy. Pathologic findings include tendon inflammation, mucoid degeneration, and fibrinoid necrosis in tendons. Microtearing and proliferation of fibroblasts have also been reported. However, the exact pathogenesis of tendinopathy is unclear.

Middle-aged adults are most susceptible to the development of tendinopathy.

In general, the prognosis is very good with rest and conservative therapy. Chronic tendinopathy can lead to weakening of the tendon and subsequent rupture. Complications of tendonitis may include chronic disability, tendon rupture, and adhesive capsulitis (ie, frozen shoulder).

Quadriceps strengthening exercises is helpful for patellar tendinopathy and change in training routine and/or equipment, if indicated. Runners with Achilles tendinopathy should wear proper footwear, run on softer surfaces, and avoid hills. Patients with tennis elbow should maintain proper backhand technique, use a less tightly strung racket, and play on slower surfaces. Range-of-motion exercises are recommended for patients with rotator cuff tendinopathy to avoid complication of adhesive capsulitis.

For patient education information, see Tendinitis and Tennis Elbow.

The history in patients with tendonitis varies with the specific disorder, as follows:

• Lateral epicondylitis - Pain at the lateral aspect of elbow is present and becomes worse with grasping and twisting[1] ; a history of playing racquet sports or manual labor is common.

• Medial epicondylitis - Medial epicondylitis is common in Little League pitchers, golfers, bowlers, and carpenters[1] ; pain is located at the medial aspect of the elbow

• Rotator cuff tendinopathy - This is associated with a history of participating in overhead activities such as painting, swimming, and throwing sports; deep ache in shoulder and painful range of motion are typical symptoms

• Bicipital tendinopathy - Pain is in the anterior shoulder in the bicipital grove; pain worsens when flexing the shoulder or supinating the forearm

• Patellar tendinopathy - Patellar tendinopathy, also referred to as jumper's knee, is associated with insidious onset of well-localized anterior knee pain; it is common in participants in jumping sports (eg, basketball, volleyball, high jumping) and running[2] ; anatomy of the patellar tendon is shown in the illustration below; pain worsens when changing position from sitting to standing or when walking or running uphill

• • The proximal patellar tendon is most commonly affected in jumper's knee.

• Popliteus tendinopathy - This type of tendinopathy is associated with lateral knee pain; running downhill is a risk factor

• Iliotibial band syndrome - This is the most common overuse syndrome of the knee and manifests as lateral knee pain[3] ; the iliotibial band is depicted in the illustration below; this syndrome may be observed in cyclists, dancers, long-distance runners, football players, and military recruits; typically pain begins after completion of a run or several minutes into a run; pain is aggravated by running down hills, lengthening stride, or sitting for long periods of time with the knee flexed

• Iliotibial band at the lateral femoral condyle, with the posterior fibers denoted.

• Shin splints - Pain is located at the anteromedial aspect of the lower leg. Shin splints have been associated with overpronation and with running on hard surfaces without proper footwear

• Achilles tendinopathy - Heel pain is evidence of Achilles tendinopathy; runners and other athletes have an increased incidence of Achilles tendinopathy; increased running distance, change in running surface, and poor footwear are associated factors

Findings on physical examination vary with the specific disorder, as follows:

Lateral epicondylitis

• Pain on palpation over the lateral epicondyle of the elbow

• Pain at the elbow with resisted dorsiflexion of the wrist

Medial epicondylitis

• Pain on palpation of the medial epicondyle of the elbow

• Pain at the elbow with resisted flexion of the wrist

Supraspinatus tendinopathy (rotator cuff tendinopathy)

• Pain on palpation over the greater tuberosity where the supraspinatus tendon inserts

• Jobe test for supraspinatus function: With both arms abducted to 90°, held slightly in front of the body, and arms fully pronated comparative resistance is placed on both arms to compare strength and presence of pain. Inability to hold the arm up or presence of pain is suggestive of rotator cuff disease.

• Hawkins test: Supraspinatus tendon impingement is suggested if pain occurs with forcible internal rotation with the patient's arm passively flexed and forward at 90°. The Hawkins test is shown in the image below.

  Hawkins test. The examiner forward flexes the arms to 90° and then forcibly internally rotates the shoulder. This movement pushes the supraspinatus tendon against the anterior surface of the coracoacromial ligament and coracoid process. Pain indicates a positive test result for supraspinatus tendonitis.

Bicipital tendinopathy

• Pain to palpation over the anterior shoulder

• Focal tenderness over groove on humerus between the greater and lesser tuberosities

• Pain with biceps resistance test (ie, shoulder flexion against resistance with elbow extended and forearm supinated)

• Positive Yergason or Speed test (ie, pain with resisted supination of the wrist or with the elbow flexed at 90° and the arm adducted against the body); these tests are shown in the images below.

  Yergason test.

  Speed test.

Patellar tendinopathy 

• Tenderness at patellar tendon insertion into lower pole of the patella

Popliteus tendinopathy

• Tenderness at the posterior-lateral joint line

• Tendon palpated most easily when lateral ankle of the affected leg rests on the opposite knee

• Lateral collateral ligament most prominent in this position; the popliteus is palpated just anterior to it and above the joint line

• With patient supine, the knee flexed to 90°, and the leg rotated internally, resisted external rotation elicits pain (diagnostic maneuver described by Webb)

Iliotibial band syndrome

• Pain localized to lateral femoral condyle - With patient supine and knee flexed to 90°, have patient extend knee while exerting pressure over the lateral femoral condyle; pain at 30° of knee flexion with compression of the iliotibial band

• Positive Renne test finding (ie, flexing knee while standing with weight on affected knee resulting in pain at approximately 30° of flexion)

• Positive Ober test result: The patient lies down with the unaffected side down and unaffected hip and knee at a 90° angle. If iliotibial band is tight, the patient will have difficulty adducting the leg beyond midline and may experience pain at the lateral aspect of the knee. The Ober test is shown below.

• The Ober test.

Shin splints

• Pain referred to anteromedial aspect of lower leg

Achilles tendinopathy

• Localized tenderness approximately 6 cm proximal to the Achilles insertion on the heel

• Pain with resisted plantar flexion of the ankle and passive dorsiflexion of the ankle

• Crepitus may be palpable with severe cases

Radiographs may be indicated if a history of trauma is present, but findings usually are negative with tendinopathy.

• Occasionally a fleck of bone may be visualized, suggesting an avulsion fracture at the site of tendinous insertion.

• A roughened appearance of the bone at the site of tendinous insertion may suggest periostitis.

• Calcium deposits along the tendon may be visualized with calcific tendinopathy.

Further imaging studies, such as ultrasonography and magnetic resonance imaging (MRI), are usually reserved for when the diagnosis is unclear or the patient's condition fails to improve with conservative management.

Ultrasonography is a rapid, noninvasive, and portable method to evaluate for tendinopathy.

• On ultrasound images, tendon changes are noted by alterations in tendon morphology and echogenicity. Mucoid degeneration and tendon tearing diminish echogenicity. Calcification can also be appreciated.

• Ultrasonography has been shown to be accurate in evaluating the rotator cuff and Achilles tendon.

• One recent study found that ultrasonography had a greater accuracy than MRI in confirming the clinical diagnosis of patellar tendinopathy.[4]

MRI is also accurate in accessing tendon pathology.

• In the United States, tendinopathy is imaged more often with MRI than with ultrasonography.

• One of the strengths of MRI is that it can also assess cartilage injuries, bony abnormalities, and ligamentous injury, which greatly aids patient management.

The goal of treatment is to reduce pain and to return to activity. Nonpharmacologic treatments of tendinopathy are as follows:

• Rest or decrease activity level. No clear recommendations are available for the duration of rest; however, patients should restrict activities that cause pain.

• Ice is recommended for the first 24-48 hours.

• Splinting and/or immobilization; sling for rotator cuff tendonitis

• Strengthening and stretching exercises can be performed once the pain has subsided. Eccentric strength training can be effective in treating tendinopathies.

Low-intensity pulsed ultrasound was shown to be no more effective than placebo in the treatment of patellar tendinopathy.[5] Transcutaneous electrical nerve stimulation (TENS) provided no benefit over primary care management in a randomized trial in 241 adults with tennis elbow.[6]

Nonsteroidal anti-inflammatory drugs (NSAIDs) are effective in relieving tendinopathy pain, and may be administered topically or orally. However, because the vast majority of tendinopathies are not inflammatory, whether NSAIDs are more effective than other analgesics is unclear.

Corticosteroid injection may be considered for patients with tendonitis in whom conservative therapy with rest, immobilization, and anti-inflammatory agents has failed.The corticosteroid (eg, triamcinolone) is typically combined with a local anesthetic (eg, lidocaine) to provide prompt analgesia; in addition, pain relief confirms the diagnosis and accurate placement of the corticosteroid.

The efficacy of locally injected steroids is debated. A systematic review concluded that steroid injections provide short-term pain relief but may not have long-term efficacy.[7] Response to injection therapy may vary with the anatomic site of tendinopathy.

A randomized, controlled trial in 165 patients with unilateral lateral epicondylalgia of longer than 6 weeks' duration found that although results at 4 weeks favored corticosteroid injection, at 1 year the rate of much improvement or complete recovery was lower with corticosteroid injection than with placebo injection (83% vs 96%, respectively; relative risk [RR], 0.86; P = 0.01)). One-year recurrence was also higher with corticosteroid versus placebo (54% vs 12%; RR, 0.23; P< 0.001).[8]

Never use injections for Achilles tendonitis, because cases of Achilles tendon rupture have been reported following a single injection of corticosteroid. Avoid repetitive corticosteroid injections in any site, as well as injection directly into a tendon, because of the risk of tendon rupture. The use of ultrasound to direct these treatments improves accuracy and performance by facilitating visualization of the target and relevant adjacent structures.[9]

In patients with calcific tendonitis of the shoulder, a systematic review concluded that ultrasound (US)-guided needling and lavage has a high success rate and low complication rate.[10] In a randomized controlled study in 48 patients with calcific tendonitis of the rotator cuff that compared the combination of barbotage and US-guided corticosteroid injection in the subacromial bursa with subacromial bursa injection alone, both treatment groups demonstrated improvement at 1-year follow-up, but clinical and radiographic results were significantly better in the barbotage group.[11] After US-guided treatment, recovery may be enhanced by use of a rehabilitation protocol that focuses on mobility, strength, and function.[12]

A retrospective evaluation of double-needle US-guided percutaneous fragmentation and lavage (DNL) in 147 patients with rotator cuff calcific tendinitis found DNL to be safe and effective, with prompt relief of pain and function restoration.[13] However, a systematic review of the efficacy of US-guided needle lavage in treating calcific tendinitis found a lack of high-quality evidence to determine the relative efficacy.[14]

Surgical therapy

Patients with symptoms resistant to conservative therapy may benefit from arthroscopic or open surgical treatment for tendon decompression and tenodesis. A Japanese study in 23 patients with chronic lateral epicondylitis who underwent arthroscopic surgery found that the procedure provided significant improvement in pain and functional recovery up to 3 months after surgery. However, the visual analog scale (VAS) for pain and satisfaction criteria during activity did not fall below 10 points until 6 months postoperatively.[15]

Isolated gastrocnemius recession has been shown to provide significant and sustained pain relief for chronic Achilles tendinopathy. Good function can be expected for activities of daily living, however ankle plantarflexion power and endurance deficits were noted.[16, 17]

Platelet-rich therapies

Platelet-rich therapies represent an experimental approach to treatment of tendinopathies and other musculoskeletal soft tissue injuries. In this technique, a quantity of the patient's blood is centrifuged and the active, platelet-rich fraction is extracted and applied to the injured tissue (eg, by injection). In theory, the growth factors produced by platelets should enhance tissue healing.

Although platelet-rich therapies are gaining wider use, however, few level one studies exist demonstrating a clear benefit.[18, 19]   Systematic reviews of the literature have concluded that evidence of benefit for the use of protein-rich plasma (PRP) as a treatment for tendinopathies varies by site. There is evidence to support PRP injections for the treatment of lateral elbow and patellar tendinopathy, whereas there remains insufficient evidence to support PRP for Achilles tendon or rotator cuff pathology.[20]  [21]

The goals of pharmacotherapy are to control pain and decrease inflammation. Nonsteroidal anti-inflammatory drugs (NSAIDs) are effective in relieving tendinopathy pain, and may be administered topically or orally. Corticosteroids may be considered when conservative therapy has failed.

Class Summary

These agents are used for the relief of mild to moderate pain. Although the effects of NSAIDs in the treatment of pain tend to be patient specific, ibuprofen usually is the drug of choice (DOC) for initial therapy. Other options include naproxen and indomethacin.

Ibuprofen (Motrin, Advil, Ibuprin, Nuprin)

Usually DOC for treatment of mild to moderate pain if no contraindications are present.

Inhibits inflammatory reactions and pain, probably by decreasing activity of the enzyme cyclooxygenase, which results in inhibition of prostaglandin synthesis.

Naproxen (Naprosyn, Aleve)

For relief of mild to moderate pain. Inhibits inflammatory reactions and pain by decreasing activity of enzyme cyclooxygenase, which results in decrease of prostaglandin synthesis.

Indomethacin (Indocin, Indochron E-R)

Rapidly absorbed; metabolism occurs in liver by demethylation, deacetylation, and glucuronide conjugation; inhibits prostaglandin synthesis.

Class Summary

These agents have both anti-inflammatory (glucocorticoid) and salt-retaining (mineralocorticoid) properties. Glucocorticoids have profound and varied metabolic effects. In addition, these agents modify the body's immune response to diverse stimuli.

Dexamethasone acetate (Decadron, AK-Dex, Alba-Dex, Dexone)

Decreases inflammation by suppressing migration of polymorphonuclear leukocytes and reducing capillary permeability. Dosage varies with degree of inflammation and size of affected area.

Methylprednisolone acetate (Solu-Medrol, Depo-Medrol, Medrol)

Decreases inflammation by suppressing migration of polymorphonuclear leukocytes and reversing increased capillary permeability.

Use 0.5-1 mL (40 mg/mL) mixed with equal or double volume of 1% local anesthetic (ie, lidocaine). Dosage varies with degree of inflammation and size of affected area.

Hydrocortisone acetate (Solu-Cortef, Cortef)

Decreases inflammation by suppressing migration of polymorphonuclear leukocytes and reversing increased capillary permeability.

Use 0.5-1 mL (25 or 50 mg/mL) mixed with equal or double volume of 1% local anesthetic (ie, lidocaine). Dosage varies with degree of inflammation and size of affected area.