Bottom-Up Kinetic Chain in Drop Landing among University Athletes with Normal Dynamic Knee Valgus

Int J Environ Res Public Health. 2020 Jun 19;17(12):4418. doi: 10.3390/ijerph17124418.

Abstract

The study investigated the influence of ankle strength and its range of motion (ROM) on knee kinematics during drop landing. Fifteen male and fifteen female university athletes with a normal range of dynamic knee valgus (DKV) (knee frontal plane projection angle: men = 3° to 8°, females = 7° to 13°) were recruited. They performed drop landing at height 30 cm and 45 cm with three-dimensional motion capture and analysis. Knee angles were compared at specific landing phases. Isokinetic ankle strength was tested at 60°/s angular velocity while the weight-bearing lunge test was conducted to evaluate ankle ROM. For males, strength for both plantarflexors and dorsiflexors were associated with knee kinematics at both heights (30 cm: r = -0.50, p = 0.03; 45 cm: r = -0.45, p = 0.05) during maximum vertical ground reaction force (MVGRF) phase. For females, ankle invertor strength and knee kinematics were associated at both 30cm (r = 0.53; p = 0.02,) and 45 cm landing heights (r = 0.49, p = 0.03), while plantarflexor strength and knee kinematics showed a significant association during initial contact (r = 0.70, p < 0.01) and MVGRF (r = 0.55, p = 0.02) phases at height 30 cm only. Male and female athletes with normal range of DKV showed a significant relationship between ankle strength and knee kinematics at specific landing phases. These relationships varied with increased landing height.

Keywords: biomechanics; collegiate athletes; injury prevention; jump-landing.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ankle Joint
  • Athletes
  • Female
  • Humans
  • Knee
  • Knee Joint* / physiology
  • Male
  • Range of Motion, Articular*