Levine Iris C, Pretty Steven P, Nouri Parvaneh K, Mourtzakis Marina, Laing Andrew C
Injury Biomechanics and Aging Laboratory, Department of Kinesiology, University of Waterloo, 200 University Ave West, Waterloo, Ontario N2L 3G1, Canada.
Injury Biomechanics and Aging Laboratory, Department of Kinesiology, University of Waterloo, 200 University Ave West, Waterloo, Ontario N2L 3G1, Canada.
J Biomech. 2018 Oct 26;80:72-78. doi: 10.1016/j.jbiomech.2018.08.029. Epub 2018 Aug 29.
While metrics of pelvis and femur geometry have been demonstrated to influence hip fracture risk, attempts at linking geometry to underlying mechanisms have focused on fracture strength. We investigated the potential effects of femur and pelvis geometry on applied loads during lateral falls on the hip. Fifteen female volunteers underwent DXA imaging to characterize two pelvis and six femur geometric features. Additionally, participants completed low-energy sideways falls on the hip; peak impact force and pressure, contact area, and moment of force applied to the proximal femur were extracted. No geometric feature was significantly associated with peak impact force. Peak moment of force was significantly associated with femur moment arm (p = 0.005). Peak pressure was positively correlated with pelvis width and femur moment arm (p < 0.05), while contact area was negatively correlated with metrics of pelvis width and femur neck length (p < 0.05). This is the first study to link experimental measures of impact loads during sideways falls with image-based skeletal geometry from human volunteers. The results suggest that while skeletal geometry has limited effects on overall peak impact force during sideways falls, it does influence how impact loads are distributed at the skin surface, in addition to the bending moment applied to the proximal femur. These findings have implications for the design of protective interventions (e.g. wearable hip protectors), and for models of fall-related lateral impacts that could incorporate the relationships between skeletal geometry, external load magnitude/distribution, and tissue-level femur loads.
虽然骨盆和股骨几何形态指标已被证明会影响髋部骨折风险，但将几何形态与潜在机制联系起来的研究主要集中在骨折强度上。我们研究了股骨和骨盆几何形态对髋部侧方跌倒时所施加负荷的潜在影响。15名女性志愿者接受了双能X线吸收测定成像，以确定两个骨盆和六个股骨的几何特征。此外，参与者完成了髋部低能量侧方跌倒；提取了峰值冲击力和压力、接触面积以及施加于股骨近端的力矩。没有几何特征与峰值冲击力显著相关。峰值力矩与股骨力臂显著相关（p = 0.005）。峰值压力与骨盆宽度和股骨力臂呈正相关（p < 0.05），而接触面积与骨盆宽度和股骨颈长度指标呈负相关（p < 0.05）。这是第一项将侧方跌倒时冲击负荷的实验测量与人类志愿者基于图像的骨骼几何形态联系起来的研究。结果表明，虽然骨骼几何形态对侧方跌倒时的总体峰值冲击力影响有限，但它确实会影响冲击负荷在皮肤表面的分布方式，以及施加于股骨近端的弯矩。这些发现对保护性干预措施（如可穿戴髋部保护器）的设计以及可能纳入骨骼几何形态、外部负荷大小/分布和组织水平股骨负荷之间关系的跌倒相关侧方冲击模型具有启示意义。
