Authors: Jacob Armstrong, Tyler Standifird
Mentors: Tyler Standifird
Insitution: Utah Valley University
Lower Limb Asymmetries in Unilateral Jump Mechanics as Possible Risk Factor for Injury in Collegiate Wrestlers
Jacob Armstrong and Tyler Standifird 1
Utah Valley University, Orem, Ut.
Injuries impose a multi-faceted burden on athletes, coaches, and sporting organizations, encompassing physical, financial, and psychological ramifications. Determining risk factors and identifying them in athletes has been a widespread goal amongst researchers and practitioners in attempts to reduce injuries. Investigating Limb asymmetries, or limb imbalances, has been a common approach in identifying such factors but has shown inconsistent correlations with injuries (Melony, 2018). Moreover, much of the current research investigates asymmetries of outward limb performance (i.e., Strength, flexibility, jump performance etc.) and not asymmetries of internal joint mechanics. Identifying relationships between internal joint asymmetries and lower limb injuries can further aid coaches, practitioners and sporting organizations in effectively identifying injury risks.
Purpose: The purpose of this study was to investigate internal joint asymmetries of the lower limbs during unilateral jump testing and their association with injuries in collegiate wrestlers.
Methods: 23 healthy Division 1 NCAA collegiate wrestlers performed single leg depth jumps from a 12-inch platform unto force plates (Bertec Inc 1000 hz). Additionally, markerless motion capture technology was used to collect video data using Qualisys Mocap cameras (Qualisys North America, Inc. Buffalo Grove, Ill). Imagery was then processed in Theia (Theia Markerless, Inc. Kingston, Ontario) to produce 3d joint locations for all the joints of the lower extremity. Each wrestler performed 3 jumps with the left leg and then 3 with the right leg for a total of 6 jump attempts. 7 total variables were calculated and recorded in Visual 3D software (Dolomite Enterprises, LLC. Tallahassee, FL) for each wrestler and leg: drop max vertical force, vertical loading rate on drop, peak knee adduction angle, peak knee abduction moment, peak knee adduction moment, peak knee flexion angle, peak knee extension moment. Averages, standard deviations and percent differences were also calculated and compared between limbs. Injury history data was also collected from each participant from the year 2021 - present day.
Results: Averaging found asymmetries in peak knee adduction angle with the left knee being greater than the right by 4.9 degrees (p=0.001), peak knee abduction moment with the right knee being greater than the left by .95 newton meters (p=0.001), and peak knee adduction moment with the left knee being greater than the right by .44 newton meters (p=0.001). All significant asymmetries were found in the frontal plane. No significant asymmetries were found in the sagittal plane. Injury history report found a total of 24 seperate lower limb injuries within the described timeframe. 16 associated with the right limb and 8 associated with the left. A total of 5 ACL injuries, 8 MCL injuries, 5 LCL Injuries, 3 meniscus injuries, and 3 ankle injuries.
Conclusion: Asymmetry trends in collegiate wrestlers potentially indicate that internal joint asymmetry is specific to sport or activity. Also, internal joint asymmetry could be a potential indicator for training protocols for overall better movement and health within the studied population. Asymmetrical values of the peak knee adduction angle, peak knee abduction moment, and peak knee adduction moment combined with the frequency of knee injuries of the participants indicate possible positive correlations between the magnitude of asymmetry discovered and injury risk.