Yoshii Yuichi, Ishii Tomoo, Tung Wen-lin
Department of Orthopaedic Surgery, Tokyo Medical University Ibaraki Medical Center, Ami, 300-0395, Japan.
J Orthop Res. 2015 May;33(5):726-30. doi: 10.1002/jor.22843. Epub 2015 Mar 2.
To assess the biomechanical effect of carpal tunnel release (CTR), we evaluated the deformation and displacement patterns of the median nerve before and after CTR in carpal tunnel syndrome (CTS) patients. Sixteen wrists of 14 idiopathic CTS patients who had open CTR and 26 wrists of 13 asymptomatic volunteers were evaluated by ultrasound. Cross-sectional images of the carpal tunnel during motion from full finger extension to flexion were recorded. The area, perimeter, aspect ratio of a minimum enclosing rectangle, and circularity of the median nerve were measured in finger extension and flexion positions. Deformation indices, determined by the flexion-extension ratio for each parameter, were compared before and after CTR. After CTR, the deformation indices of perimeter and circularity became significantly larger and the aspect ratio became significantly smaller than those before CTR (p < 0.05). Those differences were more obvious when comparing the values between the patients before CTR and the controls. Since the deformation indices after CTR are similar to the patterns of normal subjects, the surrounding structures and environment of the median nerve may be normalized upon CTR. This may be a way to tell how the median nerves recover after CTR.
为评估腕管松解术（CTR）的生物力学效应，我们评估了腕管综合征（CTS）患者在CTR前后正中神经的变形和位移模式。通过超声对14例接受开放性CTR的特发性CTS患者的16只手腕以及13名无症状志愿者的26只手腕进行了评估。记录了从手指完全伸展到屈曲运动过程中腕管的横断面图像。在手指伸展和屈曲位置测量正中神经的面积、周长、最小外接矩形的长宽比和圆形度。通过每个参数的屈伸比确定变形指数，并在CTR前后进行比较。CTR后，周长和圆形度的变形指数显著增大，长宽比显著减小（p < 0.05）。在比较CTR前患者与对照组的值时，这些差异更为明显。由于CTR后的变形指数与正常受试者的模式相似，正中神经周围的结构和环境在CTR后可能恢复正常。这可能是一种判断正中神经在CTR后如何恢复的方法。
