The Influence of Playing Position Within Recreational Netball on Lower Extremity 3D Joint Kinematics and Kinetics During a Cutting Movement and Jump Landing with regards to Potential Risk of Noncontact ACL Injury

Abstract

Landing from cutting and jumping movements potentially influences the risk of ACL injury. In netball various epidemiology studies highlight the incidence rate as a concern. Playing positions within netball may potentially increase the risk of ACL injury due to the different nature of play. This study examined whether the playing position of participants had an effect on the lower extremity joint 3D kinematics and peak VGRF. Ten female, recreational netball players (five centre court players; C,WA,WD) and five circle players; GA,GD,GS,GA) performed five trials in two movement skill conditions, a jump and a cutting movement. A CODA motion analysis system was used to collect and measure lower extremity 3D kinematics, while force plate data was used to compare peak vertical ground reaction forces (VGRF). Knee flexion angles were larger in the circle group across the entire stance phase for both the cutting movement (RMSD=12.08˚) and the jump landing (RMSD=21.65˚). The circle group had a larger flexion angle at touch down (p=0.0005) compared to centre court players. Increased hip angles were highlighted in the cutting movement for the centre court group (p=0.018, RMSD= 10.65˚) increased hip angles in the circle group during the landing phase of the jump (RMSD=17.64˚). Increased knee valgus was reported across the stance phase within the cutting movement for circle players (RMSD=2.34˚) and increased knee valgus for the centre court players in the jump landing (RMSD=5.73). A higher mean range of rotational angular displacement of the knee was reported for the circle group in the cutting condition (RMSD=2.66˚) and for the centre court group in the jump landing movement (RMSD=8.06˚). Peak VGRF was higher in the cut for the circle players (2.28BW) and for the centre court players in the jump (4.03BW). The knee flexion angles seen for both groups in both conditions are capable of causing ACL injury. This in combination with the increased valgus and increased rotational angular displacement pose a potential risk for ACL injury. These findings should be used in order to educate coaches and inform netball injury prevention programmes that are player specific.