REVIEW Risk factors for lower extremity injury: a review of the literature

Prospective studies on risk factors for lower extremity injury are reviewed. Many intrinsic and extrinsic risk factors have been implicated; however, there is little agreement with respect to the findings. Future prospective studies are needed using sufficient sample sizes of males and females, including collection of exposure data, and using established methods for identifying and classifying injury severity to conclusively determine addtional risk factors for lower extremity injury. Numerous injuries occur each year causedby sport, resulting in decreased physicalactivity and work time lost in addition to substantial medical costs. World wide, the cost of sports injuries has been estimated at $1 billion annually.1 Kraus and Conroy2 estimated that 3–5 million injuries occur annually among competi