Purpose
US high school athletes sustain millions of injuries annually. Detailed patterns of knee injuries, among the most costly sports injuries, remain largely unknown. We hypothesize that patterns of knee injuries in US high school sports differ by sport and gender.
Methods
US High school sports-related injury data were collected for 20 sports using the National High School Sports-Related Injury Surveillance System, High School RIO™. Knee injury rates, rate ratios, and injury proportion ratios were calculated.
Results
From 2005/06–2010/11, 5,116 knee injuries occurred during 17,172,376 athlete exposures (AEs) for an overall rate of 2.98 knee injuries per 10,000 AEs. Knee injuries were more common in competition than practice (RR 3.53, 95% CI 3.34–3.73). Football had the highest knee injury rate (6.29 per 10,000 AEs) followed by girls’ soccer (4.53) and girls’ gymnastics (4.23). Girls had significantly higher knee injury rates than boys in gender-comparable sports (soccer, volleyball, basketball, baseball/softball, lacrosse, swimming and diving, and track and field) (RR 1.52, 95% CI 1.39–1.65). The most commonly involved structure was the MCL (reported in 36.1% of knee injuries), followed by the patella/patellar tendon (29.5%), ACL (25.4%), meniscus (23.0%), LCL (7.9%), and PCL (2.4%). Girls were significantly more likely to sustain ACL injuries in gender-comparable sports (RR 2.38, 95% CI 1.91–2.95). Overall, 21.2% of knee injuries were treated with surgery; girls were more often treated with surgery than boys in gender-comparable sports (IPR 1.30, 95% CI 1.11–1.53).
Conclusions
Knee injury patterns differ by sport and gender. Continuing efforts to develop preventive interventions could reduce the burden of these injuries.