The epidemiology and health care burden of tennis elbow: a population-based study.

BACKGROUND: Lateral elbow tendinosis (epicondylitis) is a common condition both in primary care and specialty clinics.

PURPOSE: To evaluate the natural history (ie, incidence, recurrence, and progression to surgery) of lateral elbow tendinosis in a large population.

STUDY DESIGN: Descriptive epidemiology study.

METHODS: The study population comprised a population-based incidence cohort of patients with new-onset lateral elbow tendinosis between January 1, 2000, and December 31, 2012. The medical records of a 10% random sample (n=576) were reviewed to ascertain information on patient and disease characteristics, treatment modalities, recurrence, and progression to surgery. Age- and sex-specific incidence rates were calculated and adjusted to the 2010 US population.

RESULTS: The age- and sex-adjusted annual incidence of lateral elbow tendinosis decreased significantly over time from 4.5 per 1000 people in 2000 to 2.4 per 1000 in 2012 (P<.001). The recurrence rate within 2 years was 8.5% and remained constant over time. The proportion of surgically treated cases within 2 years of diagnosis tripled over time, from 1.1% during the 2000-2002 time period to 3.2% after 2009 (P<.00001). About 1 in 10 patients with persistent symptoms at 6 months required surgery.

CONCLUSION: The decrease in incidence of lateral elbow tendinosis may represent changes in diagnosis patterns or a true decrease in disease incidence. Natural history data can be used to help guide patients and providers in determining the most appropriate course at a given time in the disease process. The study data suggest that patients without resolution after 6 months of onset may have a prolonged disease course and may need surgical intervention.