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The Epidemiology of Knee Injuries in English Professional Rugby Union

Background Detailed injury epidemiology is an invaluable tool for reducing risks associated with sporting injuries. Very little accurate injury surveillance data exist regarding knee injuries in professional rugby. Hypotheses (1) Knee injuries have a greater impact on the game than injuries to other body locations. (2) Anterior cruciate ligament and medial collateral ligament injuries cause the greatest days absent from training and match play. Study Design Descriptive epidemiology study. Methods Medical personnel prospectively reported time-loss injuries sustained by 546 professional rugby union players from 12 clubs in England over 2 seasons, and the knee injuries were evaluated. Results Injuries to the knee accounted for the highest number of days absent due to injury (7776 days, 21%) and were characteristically severe, with a disproportionately high number of days missed per injury (37 days). Anterior cruciate ligament injuries accounted for the greatest proportion of days missed of all knee injuries (29%), followed by medial collateral ligament injuries (25%). Most severe injuries occurred during contact, mostly during a tackle, and most commonly in the final 20 minutes of a match. Injuries tended to be more common in backs. Injuries sustained during training accounted for 16% of all knee injuries. Each club studied had a mean of 10 knee injuries per season resulting in a total of 353 days absent. Conclusions The incidence of knee injuries sustained during matches was higher than that reported in all other football codes, surpassed only by rugby union at the international level. Knee injuries accounted for the highest player absence due to injury; 5% of an average playing squad were absent at any one time due to knee injuries.