Tat Jimmy, Kociolek Aaron M, Keir Peter J
Occupational Biomechanics Laboratory, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada.
J Ultrasound Med. 2015 Apr;34(4):679-87. doi: 10.7863/ultra.34.4.679.
A common pathologic finding in carpal tunnel syndrome is fibrosis and thickening of the subsynovial connective tissue. This finding suggests an etiology of excessive shear forces, with relative longitudinal displacement between the flexor tendon and adjacent subsynovial connective tissue. The purpose of this study was to validate color Doppler sonography for measurement of tendon displacement over time.
Eight unmatched fresh frozen cadaver arms were used to evaluate color Doppler sonography for measurement of tendon displacement. The middle flexor digitorum superficialis tendon was moved through a physiologic excursion of 20 mm at 3 different tendon velocities (50, 100, and 150 mm/s).
We found that color Doppler sonography provided accurate measurement of tendon displacement, with absolute errors of -0.05 mm (50 mm/s), -1.24 mm (100 mm/s), and -2.36 mm (150 mm/s) on average throughout the tendon excursion range. Evaluating relative displacement between the tendon and subsynovial connective tissue during finger flexion-extension movements also offered insight into the gliding mechanism of the subsynovial connective tissue. During flexion, we observed a curvilinear increase in relative displacement, with greater differential motion at the end range of displacement, likely due to the sequential stretch of the fibrils between successive layers of the subsynovial connective tissue. In extension, there was a linear return in relative displacement, suggesting a different unloading mechanism characterized by uniform relaxation of fibrils.
We demonstrated the validity of color Doppler displacement for use in the evaluation of relative motion. Color Doppler sonography is useful in our understanding of the behavior of the subsynovial connective tissue during tendon excursion, which may elucidate the role of finger motion in the etiology of shear injury.
腕管综合征常见的病理表现是滑膜下结缔组织纤维化和增厚。这一发现提示病因是剪切力过大，屈肌腱与相邻滑膜下结缔组织之间存在相对纵向位移。本研究的目的是验证彩色多普勒超声测量肌腱随时间的位移。
使用8个未配对的新鲜冷冻尸体手臂评估彩色多普勒超声测量肌腱位移的情况。指浅屈肌腱以3种不同的肌腱速度（50、100和150mm/s）进行20mm的生理性移动。
我们发现彩色多普勒超声能准确测量肌腱位移，在整个肌腱移动范围内，平均绝对误差分别为-0.05mm（50mm/s）、-1.24mm（100mm/s）和-2.36mm（150mm/s）。评估手指屈伸运动过程中肌腱与滑膜下结缔组织之间的相对位移，也有助于深入了解滑膜下结缔组织的滑动机制。在屈曲过程中，我们观察到相对位移呈曲线增加，在位移末端范围差异运动更大，这可能是由于滑膜下结缔组织连续层之间的纤维依次拉伸所致。在伸展过程中，相对位移呈线性恢复，表明存在一种不同的卸载机制，其特征是纤维均匀松弛。
我们证明了彩色多普勒位移测量在评估相对运动方面的有效性。彩色多普勒超声有助于我们了解肌腱移动过程中滑膜下结缔组织的行为，这可能阐明手指运动在剪切伤病因中的作用。
