Increased dynamic knee valgus has been suggested as a possible risk factor for sustaining an anterior cruciate ligament injury. A previous study has established a link between knee motion patterns and ACL injury, where dynamic knee valgus was found to be predictable for ACL injury risk. Hence, there is a need for valid and reliable clinical tests that can identify players with poor knee control, and therefore enable us to optimize preventive training programs.
The objective of this study is to assess the relationship between valgus moments in drop jumps and cutting movements measured objectively by 3D motion analysis, and poor clinical test scores in elite female football players.
The study is part of a larger cohort study where the aim is to investigate risk factors for anterior cruciate ligament injuries in elite female football players (ACL risk factor study). All players in the Norwegian elite female football league have been invited to participate, and will be tested for potential risk factors in February/March 2009-11. In the 3D motion analysis an eight-camera infrared optical tracking system will capture knee kinetics and kinematics when performing drop jumps and sports specific cutting movements. In addition, the players will also be evaluated and scored subjectively by a physical therapist when performing drop jumps and one-legged squats.
The study will enable us to assess the relationship between objective and subjective measures of knee valgus. The study will therefore represent a step towards developing clinical screening tools to identify players with an increased risk for sustaining serious knee injuries.