J Sport Rehabil. 2020 Nov 1;29(8):1069-1074. doi: 10.1123/jsr.2019-0050. Epub 2019 Nov 19.
Toe direction is an important factor affecting knee biomechanics during various movements. However, it is still unknown whether toe direction will affect trunk and pelvic movements.
To examine and clarify the effects of toe directions on biomechanics of trunk and pelvis as well as lower-extremities during single-leg drop landing (SLDL).
Descriptive laboratory study.
Research laboratory.
A total of 27 male recreational-level athletes.
INTERVENTION(S): Subjects performed SLDL under 3 different toe directions, including 0° (toe neutral), 20° (toe-in [TI]), and -20° (toe-out). SLDL was captured using a motion analysis system. Nondominant leg (27 left) was chosen for the analysis.
Peak values of kinematic and kinetic parameters during landing phase were assessed. In addition, those parameters at the timing of peak vertical ground reaction force were also assessed. The data were statistically compared among 3 different toe directions using 1-way repeated measures of analysis of variance or Friedman χ2 r test.
Peak knee abduction angle and moment in TI were significantly larger than in toe neutral and toe-out (P < .001). Moreover, peak greater anterior inclination, greater inclination, and rotation of trunk and pelvis toward the nonlanding side were seen in TI (P < .001). At the timing of peak vertical ground reaction force, trunk inclined to the landing side with larger knee abduction angle in TI (P < .001).
Several previous studies suggested that larger knee abduction angle and moment on landing side as well as trunk and pelvic inclinations during landing tasks were correlated with knee ligament injury. However, it is still unknown concerning the relationship between toe direction and trunk/pelvis movements during landing tasks. From the present study, TI during SLDL would strongly affect biomechanics of trunk and pelvis as well as knee joint, compared with toe neutral and toe-out.
足趾方向是影响各种运动中膝关节生物力学的一个重要因素。然而，足趾方向是否会影响躯干和骨盆的运动尚不清楚。
探讨并阐明单腿跳下（SLDL）时足趾方向对躯干和骨盆以及下肢生物力学的影响。
描述性实验室研究。
研究实验室。
共 27 名男性娱乐级运动员。
受试者在 3 种不同足趾方向下进行 SLDL，包括 0°（足中立）、20°（足内翻 [TI]）和-20°（足外翻）。使用运动分析系统捕获 SLDL。选择非优势腿（27 条左腿）进行分析。
评估着地阶段运动学和动力学参数的峰值。此外，还评估了在峰值垂直地面反作用力时刻的这些参数。使用单向重复测量方差分析或 Friedman χ2 r 检验，对 3 种不同足趾方向的参数进行统计学比较。
TI 时的膝关节外展角度和力矩峰值明显大于足中立和足外翻（P <.001）。此外，TI 时观察到躯干和骨盆向非着陆侧的更大前倾角、更大倾斜度和旋转（P <.001）。在峰值垂直地面反作用力时刻，TI 时，躯干向着陆侧倾斜，膝关节外展角度较大（P <.001）。
之前的几项研究表明，着陆侧的膝关节外展角度和力矩较大以及着陆时躯干和骨盆的倾斜与膝关节韧带损伤有关。然而，在着陆任务中，足趾方向与躯干/骨盆运动之间的关系尚不清楚。从本研究来看，与足中立和足外翻相比，TI 在 SLDL 时会强烈影响躯干和骨盆以及膝关节的生物力学。
