Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan; Department of Rehabilitation, Sapporo Medical University Hospital, Sapporo, Japan.
Second Division of Physical Therapy, School of Health Sciences, Sapporo Medical University, Sapporo, Japan.
J Biomech. 2020 Jan 23;99:109498. doi: 10.1016/j.jbiomech.2019.109498. Epub 2019 Nov 9.
Although shear wave elastography (SWE) has been used to indirectly measure passive tension in muscle tissues, it is unknown whether SWE can adequately evaluate passive tension in capsule tissues. This study investigated the relationship between the shear modulus and passive tension in the posterior shoulder capsule using SWE. Ten posterior middle and ten posterior inferior shoulder capsules were dissected from ten fresh-frozen cadavers; humeral head-capsule-glenoid specimens were created from each capsule. The humeral head and glenoid were immobilized with clamps in a custom-built device. Loads (0-400 g, in 25-g increments) were applied to each capsule via a pulley system; elasticity was simultaneously measured using SWE. The elasticity-load relationship of each tested capsule was analyzed by fitting a least-squares regression line to the data. Elasticity change due to creep or hysteresis effects was evaluated by comparing the elastic modulus for a 100-g load during and after the stepwise application of the loads. The observed relationship between the shear modulus and passive capsule tension was highly linear for all twenty tested capsules (p < 0.01). The mean coefficient of determination was 0.882 ± 0.075 and 0.901 ± 0.050 for the posterior middle and posterior inferior capsules, respectively. There was no difference in the shear modulus between the two 100-g load assessments for both the posterior middle (p = 0.205) and posterior inferior capsules (p = 0.161). Thus, SWE is a valid and useful method for indirectly evaluating the change in the passive tension under loading in specific posterior shoulder capsule.
虽然剪切波弹性成像（SWE）已被用于间接测量肌肉组织的被动张力，但尚不清楚 SWE 是否能充分评估囊组织的被动张力。本研究使用 SWE 研究了肩关节后囊的剪切模量与被动张力之间的关系。从 10 个新鲜冷冻尸体中解剖出 10 个后中部和 10 个后下部肩关节囊；从每个囊制备肱骨头-囊-关节盂标本。用夹具将肱骨头和关节盂固定在定制的装置中。通过滑轮系统向每个囊施加（0-400 g，每次增加 25 g）的载荷；同时使用 SWE 测量弹性。通过将最小二乘回归线拟合到数据上来分析每个测试囊的弹性与载荷关系。通过比较加载过程中及之后 100 g 载荷下的弹性模量来评估蠕变或滞后效应引起的弹性变化。对于所有 20 个测试的囊，观察到的剪切模量与被动囊张力之间的关系具有高度的线性（p<0.01）。后中部和后下部囊的平均决定系数分别为 0.882±0.075 和 0.901±0.050。在后中部（p=0.205）和后下部囊（p=0.161）中，两次 100 g 载荷评估之间的剪切模量没有差异。因此，SWE 是一种有效且有用的方法，可以间接评估特定后肩囊在加载下被动张力的变化。
