Department of Research, New York Chiropractic College, Seneca Falls, NY 13148, United States.
J Biomech. 2013 Aug 9;46(12):2053-9. doi: 10.1016/j.jbiomech.2013.05.016. Epub 2013 Jun 13.
As muscle is stretched, it reacts with increasing passive resistance. This passive force component is important for normal muscle function. Unfortunately, direct measurement of passive muscle force is still beyond the current state-of-the-art. This study aimed to investigate the feasibility of using Supersonic shear wave elastography (SSWE) to indirectly measure passive muscle force. Sixteen gastronomies pars externus and 16 tibialis anterior muscles were dissected from 10 fresh roaster chickens. For each muscle specimen, the proximal bone-tendon junction was kept intact with its tibia or femur clamped in a fixture. Calibration weights (0-400 g in 25 g per increment) were applied to the distal tendon via a pulley system and muscle elasticity was measured simultaneously using SSWE. The measurements were repeated for 3 cycles. The elasticity-load relationship of each tested muscle for each loading cycle was analyzed by fitting a least-squares regression line to the data. Test-retest reliability was evaluated using intraclass correlation coefficient (ICC). Results demonstrated that the relationships between SSWE elasticity and passive muscle force were highly linear for all the tested muscles with coefficients of determination ranging between 0.971 and 0.999. ICCs were 0.996 and 0.985, respectively, for the slope and y-intercept parameters of the regression lines, indicating excellent reliability. These findings indicate that SSWE, when carefully applied, can be a highly reliable technique for muscle elasticity measurements. The linear relationship between SSWE elasticity and passive muscle force identified in the present study demonstrated that SSWE may be used as an indirect measure of passive muscle force.
当肌肉被拉伸时，它会产生逐渐增大的被动阻力。这种被动力分量对于正常的肌肉功能很重要。不幸的是，直接测量被动肌肉力仍然超出了当前的技术水平。本研究旨在探讨使用超声剪切波弹性成像（SSWE）间接测量被动肌肉力的可行性。从 10 只新鲜烤鸡中解剖了 16 个外斜方肌和 16 个胫骨前肌。对于每个肌肉标本，近端骨-肌腱连接保持完整，其胫骨或股骨夹在夹具中。通过滑轮系统将校准砝码（0-400g，每 25g 递增一次）施加到远端肌腱上，并同时使用 SSWE 测量肌肉弹性。每个测试肌肉的每个加载周期重复测量 3 次。通过将数据拟合最小二乘回归线来分析每个测试肌肉的弹性-载荷关系。使用组内相关系数（ICC）评估测试-再测试的可靠性。结果表明，对于所有测试肌肉，SSWE 弹性与被动肌肉力之间的关系高度线性，决定系数在 0.971 到 0.999 之间。回归线斜率和 y 截距参数的 ICC 分别为 0.996 和 0.985，表明可靠性极好。这些发现表明，当谨慎应用时，SSWE 可以成为肌肉弹性测量的高度可靠技术。本研究中确定的 SSWE 弹性与被动肌肉力之间的线性关系表明，SSWE 可能被用作被动肌肉力的间接测量。
