Jeremy Mejane1, Jocelyn Faubert2, Thomas Romeas1, David R Labbe3. 1. Laboratoire de recherche en imagerie et orthopedie, Ecole de technologie superieure, Montreal, Canada; CHUM Research Center, University of Montreal, Montreal, Canada. 2. Psychophysics and Visual Perception Laboratory, School of Optometry, University of Montreal, Montreal, Canada. 3. Laboratoire de recherche en imagerie et orthopedie, Ecole de technologie superieure, Montreal, Canada; CHUM Research Center, University of Montreal, Montreal, Canada; Psychophysics and Visual Perception Laboratory, School of Optometry, University of Montreal, Montreal, Canada. Electronic address: david.labbe@etsmtl.ca.
Abstract
BACKGROUND: A large majority of anterior cruciate ligament (ACL) injuries are non-contact, most often occurring during a landing or change of direction. Recent research indicates that cognitive factors may be involved in non-contact ACL injuries. The aim of this study was to determine if a game-situation perceptual-cognitive load leads to altered landing kinematics in physically fatigued female athletes. METHODS: Nineteen female recreational athletes were recruited to perform a series of jumping and landing trials. In a first phase, eight trials were performed in an isolated condition and eight were performed while participants performed a perceptual-cognitive task. Before a second identical phase, participants underwent a muscular fatigue protocol. Knee-joint kinematics were recorded and compared between conditions using paired t-tests. RESULTS: Muscle fatigue led to statistically significant increases in peak knee abduction and peak internal knee rotation as well as a decrease in maximum knee flexion, when comparing conditions without the perceptual-cognitive task. The perceptual-cognitive task had no statistically significant effect on any knee rotations, either pre- or post-fatigue. However, a subgroup of 12 athletes showed a significant increase in knee abduction in the presence of the perceptual-cognitive task, only in the fatigued condition. CONCLUSION: A perceptual-cognitive task combined with muscle fatigue alters knee kinematics of landing for a subset of recreational athletes, potentially increasing the risk of ACL rupture. Further studies are necessary to confirm this finding and to identify characteristics of at-risk individuals to target them for injury prevention protocols.
BACKGROUND: A large majority of anterior cruciate ligament (ACL) injuries are non-contact, most often occurring during a landing or change of direction. Recent research indicates that cognitive factors may be involved in non-contact ACL injuries. The aim of this study was to determine if a game-situation perceptual-cognitive load leads to altered landing kinematics in physically fatigued female athletes. METHODS: Nineteen female recreational athletes were recruited to perform a series of jumping and landing trials. In a first phase, eight trials were performed in an isolated condition and eight were performed while participants performed a perceptual-cognitive task. Before a second identical phase, participants underwent a muscular fatigue protocol. Knee-joint kinematics were recorded and compared between conditions using paired t-tests. RESULTS:Muscle fatigue led to statistically significant increases in peak knee abduction and peak internal knee rotation as well as a decrease in maximum knee flexion, when comparing conditions without the perceptual-cognitive task. The perceptual-cognitive task had no statistically significant effect on any knee rotations, either pre- or post-fatigue. However, a subgroup of 12 athletes showed a significant increase in knee abduction in the presence of the perceptual-cognitive task, only in the fatigued condition. CONCLUSION: A perceptual-cognitive task combined with muscle fatigue alters knee kinematics of landing for a subset of recreational athletes, potentially increasing the risk of ACL rupture. Further studies are necessary to confirm this finding and to identify characteristics of at-risk individuals to target them for injury prevention protocols.