Hwang Jaejin, Knapik Gregory G, Dufour Jonathan S, Best Thomas M, Khan Safdar N, Mendel Ehud, Marras William S
Biodynamics Laboratory, Spine Research Institute, Department of Integrated Systems Engineering, The Ohio State University, 210 Baker Systems Engineering, 1971 Neil Avenue, Columbus, OH 43210, USA.
Biodynamics Laboratory, Spine Research Institute, Department of Integrated Systems Engineering, The Ohio State University, 210 Baker Systems Engineering, 1971 Neil Avenue, Columbus, OH 43210, USA; Department of Family Medicine, The Ohio State University, Martha Moorehouse Medical Plaza, 2050 Kenny Dr., Columbus, OH 43210, USA.
Clin Biomech (Bristol). 2016 Aug;37:153-159. doi: 10.1016/j.clinbiomech.2016.07.009. Epub 2016 Jul 27.
Biomechanical models have been developed to predict spinal loads in vivo to assess potential risk of injury in workplaces. Most models represent trunk muscles with straight-lines. Even though straight-line muscles behave reasonably well in simple exertions, they could be less reliable during complex dynamic exertions. A curved muscle representation was developed to overcome this issue. However, most curved muscle models have not been validated during dynamic exertions. Thus, the objective of this study was to investigate the fidelity of a curved muscle model during complex dynamic lifting tasks, and to investigate the changes in spine tissue loads.
Twelve subjects (7 males and 5 females) participated in this study. Subjects performed lifting tasks as a function of load weight, load origin, and load height to simulate complex exertions. Moment matching measures were recorded to evaluate how well the model predicted spinal moments compared to measured spinal moments from T12/L1 to L5/S1 levels.
The biologically-assisted curved muscle model demonstrated better model performance than the straight-line muscle model between various experimental conditions. In general, the curved muscle model predicted at least 80% of the variability in spinal moments, and less than 15% of average absolute error across levels. The model predicted that the compression and anterior-posterior shear load significantly increased as trunk flexion increased, whereas the lateral shear load significantly increased as trunk twisted more asymmetric during lifting tasks.
A curved muscle representation in a biologically-assisted model is an empirically reasonable approach to accurately predict spinal moments and spinal tissue loads of the lumbar spine.
已经开发出生物力学模型来预测体内脊柱负荷，以评估工作场所潜在的受伤风险。大多数模型用直线来表示躯干肌肉。尽管直线型肌肉在简单的用力动作中表现良好，但在复杂的动态用力过程中可能不太可靠。为克服这一问题，开发了一种曲线型肌肉表示法。然而，大多数曲线型肌肉模型在动态用力过程中尚未得到验证。因此，本研究的目的是调查曲线型肌肉模型在复杂动态提举任务中的逼真度，并研究脊柱组织负荷的变化。
12名受试者（7名男性和5名女性）参与了本研究。受试者根据负荷重量、负荷起始位置和负荷高度进行提举任务，以模拟复杂的用力情况。记录力矩匹配测量值，以评估该模型预测的脊柱力矩与从T12/L1至L5/S1水平测量的脊柱力矩相比的准确性。
在各种实验条件下，生物辅助曲线型肌肉模型的表现优于直线型肌肉模型。总体而言，曲线型肌肉模型预测了至少80%的脊柱力矩变异性，且各水平的平均绝对误差小于15%。该模型预测，在提举任务中，随着躯干前屈增加，压缩和前后剪切负荷显著增加，而随着躯干扭转更加不对称，横向剪切负荷显著增加。
生物辅助模型中的曲线型肌肉表示法是一种经验上合理的方法，可准确预测腰椎的脊柱力矩和脊柱组织负荷。
