周圍神經損傷是很常見的疾病，坐骨神經痛更是很常見的病徵。過去有關神經方面的研究較多是著重在病理學、電生理學或組織學上的探討，有關力學上的研究以及量化到目前來說仍然是比較少的。
本實驗利用高解析微力試驗機和差動可變磁阻轉換器，配合自製之夾具量測老鼠下肢關節角度動態變化時坐骨神經之滑動量和相對應變量，隨後探討人為椎管狹窄對於坐骨神經之應變量與滑動量產生何種程度的影響。實驗過程中主要是藉著下肢關節模擬器帶動髖關節或膝關節分別做旋轉運動，量測並記錄每個動作過程中坐骨神經之相對應變量與滑動量的變化情形。
不管是在控制組或是實驗組，當執行伸膝動作，此時坐骨神經之相對應變量與滑動量則皆有增加的趨勢(p＜0.05)，分別為20.2 ± 6.3%和0.9 ± 0.3公厘、20.7 ± 4.7%和0.5 ± 0.1公厘，在滑動方向上皆往遠端方向滑動；此外與控制組相比，椎管狹窄實驗組在滑動量上則有明顯的減少(p＜0.05)。當執行屈膝動作時，此時控制組與椎管狹窄實驗組之坐骨神經之相對應變量與滑動量則皆有減少的趨勢(p＜005)，分別減少成15.4 ± 9.2%和0.4 ± 0.2公厘、20.3 ± 10.8%和0.7 ± 0.2公厘，在滑動方向上皆往近端方向滑動。
結果發現：當受到人為椎管狹窄後，確實會對神經的應變量與滑動量造成影響，使得神經的滑動量與活動範圍降低。當膝關節執行伸展運動時，實驗組之坐骨神經滑動量有很明顯的減少，如此可能是引起坐骨神經痛病患疼痛感的最大原因，而在應變量的改變方面，只有些微的增加。

Peripheral nerve injury is a very common disease, especially the sciatica, which is resulted from the herniated intervertebral disc, spinal stenosis and spondylolisthesis. Several studies investigated the histology, pathology and electroneurophysiology of the nerve, but only few studies focus on mechanical and dynamic testing.
This study was to study the biomechanical properties of the rat sciatic nerve in vivo with cyclic movements of the hind limb in both normal rats (the control group) and an animal model of spinal stenosis (the experimental group). The Microforce Testing System integrated with DVRT and the custom-made clamp was utilized to measure the strain and excursion on the rat sciatic nerve during performing simulated motion of the hip and knee joints, respectively.
Significant increases (p＜0.05) in the strain of the sciatic nerve were observed in both groups when the knee joint was extended from flexion 45° to flexion 0° (Control: 20.2± 6.3%, Experimental: 20.7 ± 4.7%), and decreased significantly (p＜0.05) when the knee joint was flexed from flexion 45° to flexion 90° (Control: -15.4 ± 9.2%, Experimental: -20.3 ± 10.8%). There is no significant difference in the strain of the sciatic nerve between the control group and the experimental group during the knee joint movement.
The excursion in the sciatic nerve increased significantly (p＜0.05) in both groups when the knee joint was extended (Control: 0.9± 0.3mm, Experimental: 0.5 ± 0.1mm), and decreased significantly (p＜0.05) when the knee joint was flexed (Control: 0.4 ± 0.2mm, Experimental: 0.7 ± 0.2mm). There was significant difference in the excursion of the sciatic nerve between the control group and the experimental group when the knee joint was extended.
It altered the mechanical properties of the sciatic nerve following spinal stenosis induced by extradural balloon compression. The finding of this study was found that the excursion of the sciatic nerve was reduced while the nerve was stretched.

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