Nankaku Manabu, Kanzaki Hideto, Tsuboyama Tadao, Nakamura Takashi
Department of Physical Therapy, Kyoto University Hospital, Sakyo-ku, Kyoto, Japan.
Osteoporos Int. 2005 Nov;16(11):1315-20. doi: 10.1007/s00198-005-1843-2. Epub 2005 Feb 18.
The purpose of this study is to evaluate hip fracture risk in relation to fall direction, and to elucidate factors that influence the impact force in falls on the hip. Eight healthy volunteers performed deliberate falls in three directions (lateral, posterolateral and posterior) on a force platform covered by a mattress of 13 cm thickness. Fall descent motions and impact postures were examined by a three-dimensional analyzer. The maximum ground force reaction, velocity of the greater trochanter at impact, and activity of quadriceps and gluteus medius were measured. In all trials of lateral and posterolateral falls, but not of posterior falls, the subjects hit their greater trochanter directly on the mattress. The impact forces were between 2,000 N and 4,000 N. Posterolateral falls showed significantly higher velocity at impact than did posterior falls. The height and the lower limb length exhibited positive correlations with the impact force in all directions of fall. In the lateral fall, there was a positive correlation between the activity of quadriceps and the impact force. In view of the impact point, force, and velocity, the posterolateral fall seemed to carry the highest risk of hip fracture.
本研究的目的是评估与跌倒方向相关的髋部骨折风险，并阐明影响髋部跌倒时冲击力的因素。八名健康志愿者在覆盖有13厘米厚床垫的测力平台上朝着三个方向（外侧、后外侧和后方）故意跌倒。通过三维分析仪检查跌倒下降动作和撞击姿势。测量最大地面力反应、撞击时大转子的速度以及股四头肌和臀中肌的活动。在所有外侧和后外侧跌倒试验中，但不包括后侧跌倒试验，受试者的大转子直接撞击在床垫上。冲击力在2000牛至4000牛之间。后外侧跌倒在撞击时的速度明显高于后侧跌倒。身高和下肢长度在所有跌倒方向上与冲击力均呈正相关。在外侧跌倒中，股四头肌的活动与冲击力之间存在正相关。鉴于撞击点、力和速度，后外侧跌倒似乎具有最高的髋部骨折风险。
