Lee Jinkyu, Song Yongnam, Shin Choongsoo S
Department of Mechanical Engineering, Sogang University, Seoul, Republic of Korea.
Department of Mechanical Engineering, Korea University, Seoul, Republic of Korea.
Gait Posture. 2018 May;62:99-104. doi: 10.1016/j.gaitpost.2018.03.019. Epub 2018 Mar 7.
During landing, the ankle angle at initial contact (IC) exhibits relatively wide individual variation compared to the knee and hip angles. However, little is known about the effect of different IC ankle angles on energy dissipation.
The purpose of this study was to investigate the relationship between individual ankle angles at IC and energy dissipation in the lower extremity joints.
Twenty-seven adults performed single-leg landings from a 0.3-m height. Kinetics and kinematics of the lower extremity joints were measured. The relationship between ankle angles at IC and negative work, range of motion, the time to peak ground reaction force, and peak loading rate were analyzed.
The ankle angle at IC was positively correlated with ankle negative work (r = 0.80, R = 0.64, p < 0.001) and the contribution of the ankle to total (ankle, knee and hip joint) negative work (r = 0.84, R = 0.70, p < 0.001), but the ankle angle was negatively correlated with hip negative work (r = -0.46, R = 0.21, p = 0.01) and the contribution of the hip to total negative work (r = -0.61, R = 0.37, p < 0.001). The knee negative work and the contribution of the knee to total negative work were not correlated with the ankle angle at IC. The ankle angle at IC was positively correlated with total negative work (r = 0.50, R = 0.25, p < 0.01) and negatively correlated with the peak loading rate (r = -0.76, R = 0.57, p < 0.001).
These results indicated that landing mechanics changed as the ankle angle at IC increased, such that the ankle energy dissipation increased and redistributed the energy dissipation in the ankle and hip joints. Further, these results suggest that increased ankle energy dissipation with a higher IC plantar flexion angle may be a potential landing technique for reducing the risk of injury to the anterior cruciate ligament and hip musculature.
在着陆过程中，与膝关节和髋关节角度相比，初始接触（IC）时的踝关节角度表现出相对较大的个体差异。然而，关于不同的IC踝关节角度对能量消散的影响知之甚少。
本研究的目的是调查IC时个体踝关节角度与下肢关节能量消散之间的关系。
27名成年人从0.3米高度进行单腿着陆。测量下肢关节的动力学和运动学。分析IC时踝关节角度与负功、运动范围、地面反作用力峰值时间和峰值加载率之间的关系。
IC时的踝关节角度与踝关节负功呈正相关（r = 0.80，R = 0.64，p < 0.001）以及踝关节对总（踝关节、膝关节和髋关节）负功的贡献呈正相关（r = 0.84，R = 0.70，p < 0.001），但踝关节角度与髋关节负功呈负相关（r = -0.46，R = 0.21，p = 0.01）以及髋关节对总负功的贡献呈负相关（r = -0.61，R = 0.37，p < 0.001）。膝关节负功以及膝关节对总负功的贡献与IC时的踝关节角度无关。IC时的踝关节角度与总负功呈正相关（r = 0.50，R = 0.25，p < 0.01）且与峰值加载率呈负相关（r = -0.76，R = 0.57，p < 0.001）。
这些结果表明，着陆力学随着IC时踝关节角度的增加而改变，使得踝关节能量消散增加，并重新分配了踝关节和髋关节的能量消散。此外，这些结果表明，较高的IC跖屈角度增加踝关节能量消散可能是一种降低前交叉韧带和髋部肌肉组织受伤风险的潜在着陆技术。
