The ankle, knee, and hip joints work together in the sagittal plane to absorb landing forces. Reduced sagittal plane motion at the ankle may alter landing strategies at the knee and hip, potentially increasing injury risk; however, no studies have examined the kinematic relationships between the joints during jump landings. Healthy adults (N = 30; 15 male, 15 female) performed jump landings onto a force plate while three-dimensional kinematic data were collected. Joint displacement values were calculated during the loading phase as the difference between peak and initial contact angles. No relationship existed between ankle dorsiflexion displacement during landing and three-dimensional knee and hip displacements. However, less ankle dorsiflexion displacement was associated with landing at initial ground contact with larger hip flexion, hip internal rotation, knee flexion, knee varus, and smaller plantar flexion angles. Findings of the current study suggest that restrictions in ankle motion during landing may contribute to contacting the ground in a more flexed position but continuing through little additional motion to absorb the landing. Transverse plane hip and frontal plane knee positioning may also occur, which are known to increase the risk of lower extremity injury.
Rebecca L. Begalle is with the School of Kinesiology and Recreation, Illinois State University, Normal, IL. Meghan C. Walsh, J. Troy Blackburn, and Darin A. Padua are with the Department of Exercise and Sports Science, University of North Carolina at Chapel Hill, Chapel Hill, NC. Melanie L. McGrath is with the Department of Health, Physical Activity, and Recreation, University of Nebraska Omaha, Omaha, NE. Michelle C. Boling is with the Department of Clinical and Applied Movement Science, University of North Florida, Jacksonville, FL.