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Early-onset arthritis in retired National Football League players.

BACKGROUND
Injury has been identified as a potential risk factor for osteoarthritis. However, no previous study has addressed playing-career injuries and subsequent osteoarthritis in a large sample of former athletes. The purpose of this study was to describe the prevalence and determinants of arthritis and osteoarthritis in retired professional football players.


METHODS
Self-reported arthritis prevalence and retrospectively-recalled injury history were examined in a cross-sectional survey of 2,538 retired football players.


RESULTS
Football players reported a high incidence of injury from their professional playing days (52.8% reported knee injuries, 74.1% reported ligament/tendon injuries, and 14.2% reported anterior cruciate ligament tears). For those under 60 years, 40.6% of retired NFL players reported arthritis, compared with 11.7% of U.S. males (prevalence ratio = 3.5, 95% CI: 3.3 to 3.7). Within the retired NFL player cohort, osteoarthritis was more prevalent in those with a history of knee injury (prevalence ratio = 1.7, 95% CI: 1.5 to 1.9) and ligament/tendon injury (prevalence ratio = 1.6, 95% CI: 1.4 to 1.9).


CONCLUSIONS
In males under the age of 60, arthritis is over 3 times more prevalent in retired NFL players than in the general U.S. population. This excess of early-onset arthritis may be due to the high incidence of injury in football.