Edinburgh Imaging facility QMRI, School of Clinical Sciences, The University of Edinburgh, Edinburgh, EH16 4TJ, UK.
BioMedical Engineering and Imaging Institute, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, New York, NY, 10029, USA.
Geroscience. 2020 Feb;42(1):311-321. doi: 10.1007/s11357-019-00147-2. Epub 2019 Dec 21.
Determining the effect of ageing on thigh muscle stiffness using magnetic resonance elastography (MRE) and investigate whether fat fraction and muscle cross-sectional area (CSA) are related to stiffness. Six healthy older adults in their eighth and ninth decade and eight healthy young men were recruited and underwent a 3 T MRI protocol including MRE and Dixon fat fraction imaging. Muscle stiffness, fat fraction and muscle CSA were calculated in ROIs corresponding to the four quadriceps muscles (i.e. vastus lateralis (VL), vastus medialis (VM), vastus intermedius (VI), rectus femoris (RF)), combined quadriceps, combined hamstrings and adductors and whole thigh. Muscle stiffness was significantly reduced (p < 0.05) in the older group in all measured ROIs except the VI (p = 0.573) and RF (p = 0.081). Similarly, mean fat fraction was significantly increased (p < 0.05) in the older group over all ROIs with the exception of the VI (p = 0.059) and VL muscle groups (p = 0.142). Muscle CSA was significantly reduced in older participants in the VM (p = 0.003) and the combined quadriceps (p = 0.001), hamstrings and adductors (p = 0.008) and whole thigh (p = 0.003). Over the whole thigh, stiffness was significantly negatively correlated with fat fraction (r = - 0.560, p = 0.037) and positively correlated with CSA (r = 0.749, p = 0.002). Stepwise regression analysis revealed that age was the most significant predictor of muscle stiffness (p = 0.001). These results suggest that muscle stiffness is significantly decreased in healthy older adults. Muscle fat fraction and muscle CSA are also significantly changed in older adults; however, age is the most significant predictor of muscle stiffness.
使用磁共振弹性成像（MRE）确定年龄对大腿肌肉僵硬的影响，并研究脂肪分数和肌肉横截面积（CSA）是否与僵硬有关。招募了 6 名健康的老年人（80 至 90 岁）和 8 名健康的年轻人，并进行了 3T MRI 方案，包括 MRE 和 Dixon 脂肪分数成像。在对应于四个股四头肌（即股外侧肌（VL）、股内侧肌（VM）、股中间肌（VI）、股直肌（RF））、股四头肌总和、股二头肌和内收肌以及整个大腿的 ROI 中计算肌肉僵硬、脂肪分数和肌肉 CSA。在除 VI（p = 0.573）和 RF（p = 0.081）以外的所有测量 ROI 中，老年组的肌肉僵硬均显著降低（p < 0.05）。同样，在所有 ROI 中，老年组的平均脂肪分数均显著增加（p < 0.05），除 VI（p = 0.059）和 VL 肌肉群（p = 0.142）外。在 VM（p = 0.003）和股四头肌总和（p = 0.001）、股二头肌和内收肌（p = 0.008）以及整个大腿（p = 0.003）中，老年参与者的肌肉 CSA 均显著降低。在整个大腿中，僵硬与脂肪分数呈显著负相关（r = -0.560，p = 0.037），与 CSA 呈显著正相关（r = 0.749，p = 0.002）。逐步回归分析显示，年龄是肌肉僵硬的最显著预测因子（p = 0.001）。这些结果表明，健康的老年人的肌肉僵硬明显降低。老年人的肌肉脂肪分数和肌肉 CSA 也发生了显著变化；然而，年龄是肌肉僵硬的最显著预测因子。
