Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan; Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology, Suita, Japan; Research Fellow of Japan Society for the Promotion of Science, Chiyoda-ku, Japan.
J Biomech. 2021 May 7;120:110390. doi: 10.1016/j.jbiomech.2021.110390. Epub 2021 Mar 20.
An increase in the stiffness of the coracobrachialis muscle can restrain proper movement of the glenohumeral joint and scapula during arm elevation. Therefore, muscle stiffness should be reduced through stretching. The aim of this study was to determine the effective stretching position of the coracobrachialis muscle using ultrasound shear wave elastography imaging to evaluate the stiffness of individual muscles. Eighteen healthy young men participated in this study. The shear modulus of the coracobrachialis muscle was measured at the following eight shoulder positions: i) 20° abduction (Rest), ii) maximal external rotation at 90° abduction (ER2), iii) maximal internal rotation at 90° abduction (IR2), iv) maximal flexion (Flex), v) maximal extension (Ext), vi) maximal horizontal abduction at 90° abduction (Hab), vii) maximal horizontal abduction and maximal external rotation at 90° abduction (HabER), and viii) maximal horizontal abduction and maximal internal rotation at 90° abduction (HabIR). The shear modulus in each position was compared with that of Rest using the Wilcoxon signed-rank test, and a multiple comparison test was performed among the positions that exhibited significant difference. The shear modulus of all stretching positions was significantly higher than that of Rest, except for Flex. Moreover, the shear moduli of IR2, Ext, Hab, HabER, and HabIR were significantly higher than that of ER2. The shear modulus of Ext was significantly higher than that of HabIR. The coracobrachialis muscle could be stretched effectively at IR2, Ext, Hab, HabER, and HabIR. Among these positions, Ext, Hab, and HabER are recommended for clinical settings.
三角肌肱二头肌的僵硬程度增加会限制肩关节和肩胛骨在手臂抬起过程中的正常运动。因此，应该通过拉伸来降低肌肉僵硬程度。本研究旨在使用超声剪切波弹性成像来确定三角肌肱二头肌的有效拉伸位置，以评估单个肌肉的僵硬程度。18 名健康的年轻男性参与了这项研究。在以下 8 个肩部位置测量三角肌肱二头肌的剪切模量：i）20°外展（Rest），ii）90°外展时最大外旋（ER2），iii）90°外展时最大内旋（IR2），iv）最大屈曲（Flex），v）最大伸展（Ext），vi）90°外展时最大水平外展（Hab），vii）90°外展时最大水平外展和最大外旋（HabER），以及 viii）90°外展时最大水平外展和最大内旋（HabIR）。使用 Wilcoxon 符号秩检验比较每个位置的剪切模量与 Rest 的差异，并对显示显著差异的位置进行多重比较检验。除 Flex 外，所有拉伸位置的剪切模量均明显高于 Rest。此外，IR2、Ext、Hab、HabER 和 HabIR 的剪切模量明显高于 ER2。Ext 的剪切模量明显高于 HabIR。IR2、Ext、Hab、HabER 和 HabIR 可以有效地拉伸三角肌肱二头肌。在这些位置中，Ext、Hab 和 HabER 推荐用于临床环境。
