Griskevicius Julius, Linkel Arturas, Pauk Jolanta
Vilnius Gediminas Technical University, Vilnius, Lithuania.
Białystok University of Technology, Białystok, Poland.
Acta Bioeng Biomech. 2014;16(1):37-44.
The purpose of the paper is to present a dynamic model of bicyclist's lumbar spine for the evaluation of linear and angular variation of intervertebral distance in sagittal plane. Ten degrees of freedom biomechanical model of the spine was solved numerically. Larger loads acting on a cyclist spine occur mostly while sitting in a sport position in comparison with recreation or middle sitting. The load on lumbar spine region is influenced by cycle's tire pressure, road bumps and wheeling speed. The biggest linear and angular displacements were found between L4-L5 vertebras. The biggest load protractile spine muscle experiences in the sport sitting position. Maximum vertebrae rotation and linear variation values in wheeling regime with 1.5 Bar tyres pressure and at a speed of 10 km/h are 0.46° and 0.46 mm. Maximum vertebrae rotation and linear variation values for a 23 year old, 1.74 m high and 73 kg of mass (bicycle mass~7 kg) man in wheeling regime with 3.5 Bar tyres pressure and at a speed of 30 km/h are 3.9° and 1.23 mm. The biggest variation of rotation in sagittal plane between two nearest lumbar spines is about 1°. Because of this displacement the frontal part of last mentioned disc is compressed with 530 N more and dorsal disc part as much less.
本文的目的是提出一个自行车骑行者腰椎的动态模型，用于评估矢状面内椎间距离的线性和角度变化。对脊柱的十自由度生物力学模型进行了数值求解。与休闲骑行或正常坐姿相比，骑行者脊柱承受较大负荷主要发生在处于运动姿势骑行时。腰椎区域的负荷受自行车轮胎压力、路面颠簸和骑行速度的影响。在L4-L5椎体之间发现了最大的线性和角位移。在运动坐姿下，脊柱肌肉承受的负荷最大。在轮胎压力为1.5巴、速度为10公里/小时的骑行状态下，椎骨的最大旋转和线性变化值分别为0.46°和0.46毫米。对于一名23岁、身高1.74米、体重73公斤（自行车质量约7公斤）的男子，在轮胎压力为3.5巴、速度为30公里/小时的骑行状态下，椎骨的最大旋转和线性变化值分别为3.9°和1.23毫米。两个相邻腰椎在矢状面内的最大旋转变化约为1°。由于这种位移，上述椎间盘的前部受到的压力增加了530牛，而后部椎间盘受到的压力则减少了同样的量。
