MOTION Science Institute, Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, Chapel Hill, NC.
Department of Orthopaedics, University of North Carolina at Chapel Hill, Chapel Hill, NC.
Med Sci Sports Exerc. 2021 Jun 1;53(6):1228-1234. doi: 10.1249/MSS.0000000000002572.
This study aimed 1) to determine whether talar cartilage deformation measured via ultrasonography (US) after standing and hopping loading protocols differs between chronic ankle instability (CAI) patients and healthy controls and 2) to determine whether the US measurement of cartilage deformation reflects viscoelasticity between standing and hopping protocols.
A total of 30 CAI and 30 controls participated. After a 60-min off-loading period, US images of the talar cartilage were acquired before and after static (2-min single-leg standing) and dynamic (60 single-leg forward hops) loading conditions. We calculated cartilage deformation by assessing the change in average thickness (mm) for overall, medial, and lateral talar cartilage. The independent variables include time (Pre60 and postloading), condition (standing and dynamic loading), and group (CAI and control). A three-way mixed-model repeated-measures ANCOVA and appropriate post hoc tests were used to compare cartilage deformation between the groups after static and dynamic loading.
After the static loading condition, those with CAI had greater talar cartilage deformation compared with healthy individuals for overall (-10.87% vs -6.84%, P = 0.032) and medial (-12.98% vs -5.80%, P = 0.006) talar cartilage. Similarly, the CAI group had greater deformation relative to the control group for overall (-8.59% vs -3.46%, P = 0.038) and medial (-8.51% vs -3.31%, P = 0.043) talar cartilage after the dynamic loading condition. In the combined cohort, cartilage deformation was greater after static loading compared with dynamic in overall (-8.85% vs -6.03%, P = 0.003), medial (-9.38% vs -5.91%, P = 0.043), and lateral (-7.90% vs -5.65%, P = 0.009) cartilage.
US is capable of detecting differences in cartilage deformation between those with CAI and uninjured controls after standardized physiologic loads. Across both groups, our results demonstrate that static loading results in greater cartilage deformation compared with dynamic loading.
本研究旨在：1）确定经超声（US）测量的距骨软骨在站立和跳跃负荷后是否存在差异，该差异在慢性踝关节不稳定（CAI）患者和健康对照组之间是否存在差异；2）确定 US 测量的软骨变形是否反映了站立和跳跃协议之间的粘弹性。
共纳入 30 例 CAI 患者和 30 例健康对照组。在 60 分钟的去负荷期后，在静态（2 分钟单腿站立）和动态（60 次单腿向前跳跃）负荷条件下，分别在距骨软骨的 US 图像采集前后，对其进行评估。通过评估距骨软骨的平均厚度（mm）变化，我们计算了软骨变形。独立变量包括时间（Pre60 和负荷后）、条件（站立和动态负荷）和组（CAI 和对照组）。采用三因素混合模型重复测量方差分析和适当的事后检验比较了两组在静态和动态负荷后的软骨变形。
在静态负荷条件下，与健康个体相比，CAI 患者的距骨软骨整体（-10.87%比-6.84%，P = 0.032）和内侧（-12.98%比-5.80%，P = 0.006）距骨软骨的变形更大。同样，与对照组相比，CAI 组在动态负荷条件下的整体（-8.59%比-3.46%，P = 0.038）和内侧（-8.51%比-3.31%，P = 0.043）距骨软骨的变形也更大。在联合队列中，与动态负荷相比，静态负荷后整体（-8.85%比-6.03%，P = 0.003）、内侧（-9.38%比-5.91%，P = 0.043）和外侧（-7.90%比-5.65%，P = 0.009）距骨软骨的变形更大。
US 能够检测出 CAI 患者和未受伤对照组之间标准化生理负荷后软骨变形的差异。在两组中，我们的结果均表明，与动态负荷相比，静态负荷会导致更大的软骨变形。
