eMedicine Specialties > Emergency Medicine > Rheumatology

Tendonitis

Mark Steele, MD, Associate Dean for Truman Medical Center Programs, Professor, Department of Emergency Medicine, University of Missouri-Kansas City
Jeffrey G Norvell, MD, Clinical Assistant Professor of Emergency Medicine, University of Kansas School of Medicine

Updated: Mar 31, 2008

Introduction

Background

Tendonitis is an inflammatory condition characterized by pain at tendinous insertions into bone.  The term tendinosis refers to the histopathologic finding of tendon degeneration. The term tendinopathy is a generic term used to describe a common clinical condition affecting the tendons, which causes pain, swelling, or impaired performance. Because of the fact that most pain from tendon conditions is not actually inflammatory in nature, tendinopathy may be a better term than tendonitis.

Common sites of tendinopathy include the following:

• Rotator cuff of the shoulder (ie, supraspinatus) and bicipital tendons
• Insertion of the wrist extensors (ie, lateral epicondylitis, tennis elbow) and flexors (ie, medial epicondylitis) at the elbow
• Patellar and popliteal tendons and iliotibial band at the knee
• Insertion of the posterior tibial tendon in the leg (ie, shin splints)
• Achilles tendon at the heel

For a related CME activity, see CME - Tendinopathy -- From Basic Science to Treatment.

Pathophysiology

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.

Mortality/Morbidity

Chronic tendinopathy can lead to weakening of the tendon and subsequent rupture.

Age

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

Clinical

History

• Lateral epicondylitis
  • Pain at the lateral aspect of elbow is present and becomes worse with grasping and twisting.
  • 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.
  • 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
  • This is associated with insidious onset of well-localized anterior knee pain. Patellar tendinopathy is common in those who participate in jumping sports (eg, basketball, volleyball, high jumping) and running.
  • Pain worsens when changing position from sitting to standing or when walking or running uphill.
• Popliteus tendinopathy
  • This type of tendinopathy is associated with lateral knee pain.
  • Running downhill is a risk factor.
• Iliotibial band syndrome
  • Iliotibial band syndrome is the most common overuse syndrome of the knee and results in lateral knee pain.
  • 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.
• Shin splints
  • Pain is located at the anteromedial aspect of the lower leg. Shin splints have been associated with overpronation.
    
    For a related CME/CE activity, see CME/CE - Medical Interventions Effectively Treat Overuse Injuries in Adult Endurance Athletes.
  • Runners running on hard surfaces without proper footwear are predisposed to this condition.
• Achilles tendinopathy
  • Heel pain is evidence of Achilles tendinopathy.
  • Runners and other athletes have an increased incidence of Achilles tendinopathy. Increased mileage, change in running surface, and poor footwear are associated factors.

Physical

• 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°.
• 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)
• 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.
• 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

Causes

Overuse is the most common etiology.

• Physical work-related factors
  • Intense, repeated, and sustained exertion
  • Awkward, sustained, or extreme postures
  • Insufficient recovery time between activities
  • Vibration
  • Cold temperatures
• Psychosocial work-related factors
  • Monotonous work
  • Time pressure
  • High work load
  • Lack of peer support
  • Poor supervisor-employee relationship
• Oral and parenteral fluoroquinolone treatment
  • Multiple case reports of tendinopathy (particularly Achilles tendinopathy) and some reports of tendon rupture in patients receiving oral and parenteral fluoroquinolone treatment have suggested a relationship between these agents and the development of tendinopathy.
    • The Food and Drug Administration has added a warning about the risk of tendinopathy and tendon rupture on the label of fluoroquinolones marketed in the United States.
    • Risk factors include concomitant steroid therapy and renal insufficiency.
  • Tendinopathy can occur within a few days or up to 6 months following the completion of a course of quinolones. A direct relationship exists between length of treatment and severity of symptoms.
  • Tendon rupture can occur without a history of specific trauma.
  • The pathologic mechanisms responsible for tendinopathy from fluoroquinolone use are multifactorial. Studies have implicated ischemic, toxic, and matrix-degrading processes.
  • The Achilles tendon is commonly involved, but shoulder and hand involvement has been reported. Unlike with other etiologies, bilateral tendinitis is common.

Differential Diagnoses

Other Problems to Be Considered

Osteoarthritis

Workup

Imaging Studies

• 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.¹
  • 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.

Treatment

Emergency Department Care

The goal of treatment is to reduce pain and to return to activity.

Treatments of tendinopathy are listed below.

• 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.
• Nonsteroidal anti-inflammatory drugs (NSAIDs) are effective in relieving tendinopathy pain. However, because the vast majority of tendinopathies are not inflammatory, whether NSAIDs are more effective than other analgesics is unclear.
• 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.²
• Peritendinous lidocaine/corticosteroid injection
  • Consider this injection for patients with tendonitis in whom conservative therapy with rest, immobilization, and anti-inflammatory agents has failed.
  • The efficacy of locally injected steroids is debated.
  • Never inject into the Achilles tendon 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.

Consultations

An ED consultation is rarely necessary for tendonitis.

Medication

The goals of pharmacotherapy are to control pain and decrease inflammation.

Nonsteroidal anti-inflammatory drugs (NSAIDs)

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.

Dosing

Adult

400 mg PO q4-6h, 600 mg PO q6h, or 800 mg PO q8h while symptoms persist; not to exceed 3.2 g/d

Pediatric

<6 months: Not established
6 months to 12 years: 20-40 mg/kg/d PO divided tid/qid; start at lower end of dosing range and titrate upward; not to exceed 2.4 g/d
>12 years: Administer as in adults

Interactions

Coadministration with aspirin increases risk of inducing serious NSAID-related adverse effects; probenecid may increase concentrations and possibly toxicity of NSAIDs; may decrease effects of hydralazine, captopril, and beta-blockers; may decrease diuretic effects of furosemide and thiazides; monitor PT closely (instruct patients to watch for signs of bleeding); may increase risk of methotrexate toxicity; phenytoin levels may be increased when administered concurrently

Contraindications

Documented hypersensitivity; cross-sensitivity to other NSAIDs may occur; peptic ulcer disease; recent GI bleeding or perforation; renal insufficiency; high risk of bleeding

Precautions

Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals

D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus

Precautions

Caution in congestive heart failure, hypertension, and decreased renal and hepatic function; caution in anticoagulation abnormalities or during anticoagulant therapy

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.

Dosing

Adult

200-250 mg PO q6-8h or 500 mg PO bid; not to exceed 1.25 g/d; may increase to 1.5 g/d for limited periods

Pediatric

<2 years: Not established
>2 years: 2.5 mg/kg/dose PO; not to exceed 10 mg/kg/d

Interactions

Coadministration with aspirin increases risk of inducing serious NSAID-related adverse effects; probenecid may increase concentrations and possibly toxicity of NSAIDs; may decrease effects of hydralazine, captopril, and beta-blockers; may decrease diuretic effects of furosemide and thiazides; monitor PT closely (instruct patients to watch for signs of bleeding); may increase risk of methotrexate toxicity; phenytoin levels may be increased when administered concurrently

Contraindications

Documented hypersensitivity; peptic ulcer disease; recent GI bleeding or perforation; renal insufficiency; high risk of bleeding

Precautions

Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals

D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus

Precautions

Acute renal insufficiency, interstitial nephritis, hyperkalemia, hyponatremia, and renal papillary necrosis may occur; patients with preexisting renal disease or compromised renal perfusion risk acute renal failure; leukopenia occurs rarely, is transient, and usually returns to normal during therapy; persistent leukopenia, granulocytopenia, or thrombocytopenia warrants further evaluation and may require discontinuation of drug

Indomethacin (Indocin, Indochron E-R)

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

Dosing

Adult

25-50 mg PO bid/tid
75 mg SR PO bid; not to exceed 200 mg/d

Pediatric

1-2 mg/kg/d PO divided bid/qid; not to exceed 4 mg/kg/d or 150-200 mg/d

Interactions

Coadministration with aspirin increases risk of inducing serious NSAID-related adverse effects; probenecid may increase concentrations and possibly toxicity of NSAIDs; may decrease effects of hydralazine, captopril, and beta-blockers; may decrease diuretic effects of furosemide and thiazides; may increase PT when taking anticoagulants (instruct patients to watch for signs of bleeding); may increase risk of methotrexate toxicity; phenytoin levels may be increased when administered concurrently

Contraindications

Documented hypersensitivity; GI bleeding or renal insufficiency

Precautions

Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals

D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus

Precautions

Acute renal insufficiency, hyperkalemia, hyponatremia, interstitial nephritis, and renal papillary necrosis may occur; increases risk of acute renal failure in patients with preexisting renal disease or compromised renal perfusion; reversible leukopenia may occur (discontinue if persistent leukopenia, granulocytopenia, or thrombocytopenia)

Corticosteroids

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.

Dosing

Adult

4-16 mg intralesionally (0.5-1 mL) mixed with equal or double volume of 1% local anesthetic (ie, lidocaine)

Pediatric

<12 years: Not established
>12 years: Administer as in adults

Interactions

Effects decrease with coadministration of barbiturates, phenytoin, and rifampin; decreases effect of salicylates and vaccines used for immunization

Contraindications

Documented hypersensitivity; active bacterial or fungal infection

Precautions

Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals

Precautions

Increases risk of multiple complications, including severe infections; monitor adrenal insufficiency when tapering drug; abrupt discontinuation of glucocorticoids may cause adrenal crisis; hyperglycemia, edema, osteonecrosis, myopathy, PUD, hypokalemia, osteoporosis, euphoria, psychosis, myasthenia gravis, growth suppression, and infections are possible complications of glucocorticoid use

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.

Dosing

Adult

Tendon sheath inflammation: 4-30 mg intralesionally

Pediatric

Not established

Interactions

Coadministration with digoxin may increase digitalis toxicity secondary to hypokalemia; estrogens may increase levels of methylprednisolone; phenobarbital, phenytoin, and rifampin may decrease levels of methylprednisolone (adjust dose); monitor patients for hypokalemia when taking medication concurrently with diuretics

Contraindications

Documented hypersensitivity; viral, fungal, or tubercular skin infections

Precautions

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions

Hyperglycemia, edema, osteonecrosis, PUD, hypokalemia, osteoporosis, euphoria, psychosis, growth suppression, myopathy, and infections are possible complications of glucocorticoid use

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.

Dosing

Adult

5-12.5 mg intralesionally

Pediatric

Not established

Interactions

Corticosteroid clearance may decrease with estrogens; may increase digitalis toxicity secondary to hypokalemia

Contraindications

Documented hypersensitivity; viral, fungal, or tubercular skin infections

Precautions

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions

Caution in hyperthyroidism, osteoporosis, peptic ulcer, cirrhosis, nonspecific ulcerative colitis, diabetes, and myasthenia gravis

Follow-up

Further Inpatient Care

• Patients with symptoms resistant to conservative therapy rarely require arthroscopic or open surgical treatment for tendon decompression and tenodesis.

Further Outpatient Care

• Follow-up care with patient's primary care provider within 1-2 weeks is appropriate in most cases of tendinopathy.
• Specialty follow-up care with orthopedics may be indicated for patients with symptoms resistant to conservative therapy.

Complications

• Chronic disability
• Tendon rupture
• Adhesive capsulitis (ie, frozen shoulder)

Prognosis

• In general, the prognosis is very good with rest and conservative therapy.

Patient Education

• Quadriceps strengthening exercises for patellar tendinopathy
• 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 excellent patient education resources, visit eMedicine's Foot, Ankle, Knee, and Hip Center and Hand, Wrist, Elbow, and Shoulder Center. Also, see eMedicine's patient education articles Tendinitis and Tennis Elbow.

Miscellaneous

Medicolegal Pitfalls

• Achilles tendon corticosteroid injection, steroid injection directly into a tendon, or repetitive peritendinous corticosteroid injections may result in tendon rupture.
• Prolonged shoulder immobilization for rotator cuff tendinopathy can result in adhesive capsulitis.

References

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2. Warden SJ, Metcalf BR, Kiss ZS, Cook JL, Purdam CR, Bennell KL, et al. Low-intensity pulsed ultrasound for chronic patellar tendinopathy: a randomized, double-blind, placebo-controlled trial. Rheumatology (Oxford). Apr 2008;47(4):467-71. [Medline].

3. Adler RS, Finzel KC. The complementary roles of MR imaging and ultrasound of tendons. Radiol Clin North Am. Jul 2005;43(4):771-807, ix. [Medline].

4. Biundo JJ Jr, Mipro RC Jr, Fahey P. Sports-related and other soft-tissue injuries, tendinitis, bursitis, and occupation-related syndromes. Curr Opin Rheumatol. Mar 1997;9(2):151-4. [Medline].

5. Biundo JJ, Irwin RW, Umpierre E. Sports and other soft tissue injuries, tendinitis, bursitis, and occupation-related syndromes. Curr Opin Rheumatol. Mar 2001;13(2):146-9. [Medline].

6. Crawford JO, Laiou E. Conservative treatment of work-related upper limb disorders: a review. Occup Med (Lond). Jan 2007;57(1):4-17. [Medline].

7. Garrick JG, Webb DR. Sports Injuries: Diagnosis and Management. Philadelphia, Pa: WB Saunders; 1990.

8. Gold L, Igra H. Levofloxacin-induced tendon rupture: a case report and review of the literature. J Am Board Fam Pract. Sep-Oct 2003;16(5):458-60. [Medline].

9. Hales TR, Bernard BP. Epidemiology of work-related musculoskeletal disorders. Orthop Clin North Am. Oct 1996;27(4):679-709. [Medline].

10. Harrell RM. Fluoroquinolone-induced tendinopathy: what do we know?. South Med J. Jun 1999;92(6):622-5. [Medline].

11. Khaund R, Flynn SH. Iliotibial band syndrome: a common source of knee pain. Am Fam Physician. Apr 15 2005;71(8):1545-50. [Medline].

12. McLoughlin RF, Raber EL, Vellet AD, et al. Patellar tendinitis: MR imaging features, with suggested pathogenesis and proposed classification. Radiology. Dec 1995;197(3):843-8. [Medline].

13. Sharma P, Maffulli N. Tendon injury and tendinopathy: healing and repair. J Bone Joint Surg Am. 2005;87-A:187-202. [Medline].

14. Sorosky B, Press J, Plastaras C, Rittenberg J. The practical management of Achilles tendinopathy. Clin J Sport Med. Jan 2004;14(1):40-4. [Medline].

15. Tytherleigh-Strong G, Hirahara A, Miniaci A. Rotator cuff disease. Curr Opin Rheumatol. Mar 2001;13(2):135-45. [Medline].

16. van Tulder M, Malmivaara A, Koes B. Repetitive strain injury. Lancet. May 26 2007;369(9575):1815-22. [Medline].

17. Wang JH, Iosifidis MI, Fu FH. Biomechanical basis for tendinopathy. Clin Orthop Relat Res. Feb 2006;443:320-32. [Medline].

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Keywords

tendonitis, pain at tendinous insertions, lateral epicondylitis, tennis elbow, medial epicondylitis, calcific tendinitis, rotator cuff tendonitis, patellar tendonitis, popliteus tendonitis, iliotibial band syndrome, shinsplints, Achilles tendonitis, supraspinatus tendonitis, bicipital tendonitis, Yergason test, Speed test, Renne test, tendonopathy, tendinopathy, tendinitis

Contributor Information and Disclosures

Author

Mark Steele, MD, Associate Dean for Truman Medical Center Programs, Professor, Department of Emergency Medicine, University of Missouri-Kansas City
Mark Steele, MD is a member of the following medical societies: American Academy of Emergency Medicine and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Coauthor(s)

Jeffrey G Norvell, MD, Clinical Assistant Professor of Emergency Medicine, University of Kansas School of Medicine
Jeffrey G Norvell, MD is a member of the following medical societies: American College of Emergency Physicians and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Medical Editor

Richard S Krause, MD, Clinical Assistant Professor, Residency Program Director, Department of Emergency Medicine, State University of New York at Buffalo School of Medicine
Richard S Krause, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Emergency Medicine, American College of Emergency Physicians, and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: Nothing to disclose.

Managing Editor

Gino A Farina, MD, Program Director, Associate Professor of Clinical Emergency Medicine, Department of Emergency Medicine, Long Island Jewish Medical Center, Albert Einstein College of Medicine
Gino A Farina, MD is a member of the following medical societies: American Academy of Emergency Medicine, American College of Emergency Physicians, and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

CME Editor

John D Halamka, MD, MS, Associate Professor of Medicine, Harvard Medical School, Beth Israel Deaconess Medical Center; Chief Information Officer, CareGroup Healthcare System and Harvard Medical School; Attending Physician, Division of Emergency Medicine, Beth Israel Deaconess Medical Center
John D Halamka, MD, MS is a member of the following medical societies: American College of Emergency Physicians, American Medical Informatics Association, Phi Beta Kappa, and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Chief Editor

Rick Kulkarni, MD, Medical Director, Assistant Professor of Surgery, Section of Emergency Medicine, Yale-New Haven Hospital
Rick Kulkarni, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Emergency Medicine, American College of Emergency Physicians, American Medical Association, American Medical Informatics Association, Phi Beta Kappa, and Society for Academic Emergency Medicine
Disclosure: WebMD Salary Employment

The authors and editors of eMedicine gratefully acknowledge the contributions of previous editor, Charles V Pollack Jr, MD, to the development and writing of this article.

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