Weston Eric B, Khan Safdar N, Marras William S
a Spine Research Institute - Biodynamics Laboratory , The Ohio State University , Columbus , OH , USA.
b Department of Integrated Systems Engineering , The Ohio State University , Columbus , OH , USA.
Ergonomics. 2017 Dec;60(12):1754-1765. doi: 10.1080/00140139.2017.1344445. Epub 2017 Jun 26.
The objective of this study was to determine how simulated manual wheelchair pushing influences biomechanical loading to the lumbar spine and shoulders. Sixty-two subjects performed simulated wheelchair pushing and turning in a laboratory. An electromyography-assisted biomechanical model was used to estimate spinal loads. Moments at the shoulder joint, external hand forces and net turning torque were also assessed. Multiple linear regression techniques were employed to develop biomechanically based wheelchair pushing guidelines relating resultant hand force or net torque to spinal load. Male subjects experienced significantly greater spinal loading (p < 0.01), and spine loads were also increased for wheelchair turning compared to straight wheelchair pushing (p < 0.001). Biomechanically determined maximum acceptable resultant hand forces were 17-18% lower than psychophysically determined limits. We conclude that manual wheelchair pushing and turning can pose biomechanical risk to the lumbar spine and shoulders. Psychophysically determined maximum acceptable push forces do not appear to be protective enough of this biomechanical risk. Practitioner Summary: This laboratory study investigated biomechanical risk to the low back and shoulders during simulated wheelchair pushing. Manual wheelchair pushing posed biomechanical risk to the lumbar spine (in compression and A/P shear) and to the shoulders. Biomechanically determined wheelchair pushing thresholds are presented and are more protective than the closest psychophysically determined equivalents.
本研究的目的是确定模拟手动轮椅推行如何影响腰椎和肩部的生物力学负荷。62名受试者在实验室中进行了模拟轮椅推行和转弯。使用肌电图辅助生物力学模型来估计脊柱负荷。还评估了肩关节力矩、手部外力和净转弯扭矩。采用多元线性回归技术制定基于生物力学的轮椅推行指南，将合成手力或净扭矩与脊柱负荷联系起来。男性受试者的脊柱负荷显著更大（p < 0.01），与直线轮椅推行相比，轮椅转弯时脊柱负荷也增加（p < 0.001）。生物力学确定的最大可接受合成手力比心理物理学确定的极限低17 - 18%。我们得出结论，手动轮椅推行和转弯会对腰椎和肩部造成生物力学风险。心理物理学确定的最大可接受推力似乎对这种生物力学风险的保护作用不够。从业者总结：本实验室研究调查了模拟轮椅推行过程中对下背部和肩部的生物力学风险。手动轮椅推行对腰椎（压缩和前后剪切）和肩部造成生物力学风险。给出了生物力学确定的轮椅推行阈值，这些阈值比最接近的心理物理学确定的阈值更具保护作用。
