Long-term followup of knee injuries in high school football players.

Twenty-three American football participants were studied 20 years after high school competition, as well as 11 age-matched controls, to assess the development of knee osteoarthritis. No statistically significant increase in osteoarthritis could be demonstrated radiographically, subjectively, or objectively. A significant increase in knee joint osteoarthritis was found in the subgroup of football players who had sustained a knee injury.