Department of Neurologic Surgery, Mayo Clinic, Rochester, MN 55905, USA.
J Neurosci Methods. 2013 Mar 30;214(1):37-44. doi: 10.1016/j.jneumeth.2013.01.003. Epub 2013 Jan 11.
Peripheral nerve reconstruction is seldom done in the acute phase of nerve injury due to concomitant injuries and the uncertainty of the extent of nerve damage. A proper model that mimics true clinical scenarios is critical but lacking. The aim of this study is to develop a standardized, delayed sciatic nerve repair model in rats and validate the feasibility of direct secondary neurrorraphy after various delay intervals. Immediately or 1, 4, 6, 8 and 12 weeks after sciatic nerve transection, nerve repair was carried out. A successful tension-free direct neurorraphy (TFDN) was defined when the gap was shorter than 4.0 mm and the stumps could be reapproximated with 10-0 stitches without detachment. Compound muscle action potential (CMAP) was recorded postoperatively. Gaps between the two nerve stumps ranged from 0 to 9 mm, the average being 1.36, 2.85, 3.43, 3.83 and 6.4 mm in rats with 1, 4, 6, 8 and 12 week delay, respectively. The rate of successful TFDN was 78% overall. CMAP values of 1 and 4 week delay groups were not different from the immediate repair group, whereas CMAP amplitudes of 6, 8 and 12 week delay groups were significantly lower. A novel, standardized delayed nerve repair model is established. For this model to be sensitive, the interval between nerve injury and secondary repair should be at least over 4 weeks. Thereafter the longer the delay, the more challenging the model is for nerve regeneration. The choice of delay intervals can be tailored to meet specific requirements in future studies.
周围神经重建在神经损伤的急性期很少进行，这是由于同时存在的损伤和神经损伤程度的不确定性。一个模拟真实临床情况的适当模型是至关重要的，但却缺乏这样的模型。本研究的目的是在大鼠中建立一种标准化的、延迟的坐骨神经修复模型，并验证在不同延迟时间后直接进行二次神经吻合的可行性。在坐骨神经切断后立即或 1、4、6、8 和 12 周进行神经修复。当间隙小于 4.0mm，并且可以用 10-0 缝线无分离地重新接近残端时，定义成功的无张力直接神经吻合（TFDN）。术后记录复合肌肉动作电位（CMAP）。两个神经残端之间的间隙从 0 到 9mm 不等，分别为 1 周、4 周、6 周、8 周和 12 周延迟大鼠的平均间隙为 1.36、2.85、3.43、3.83 和 6.4mm。总的 TFDN 成功率为 78%。1 周和 4 周延迟组的 CMAP 值与即刻修复组无差异，而 6 周、8 周和 12 周延迟组的 CMAP 幅度明显降低。建立了一种新的、标准化的延迟神经修复模型。为了使该模型具有敏感性，神经损伤和二次修复之间的间隔时间至少应超过 4 周。此后，延迟时间越长，神经再生的难度就越大。延迟时间的选择可以根据未来研究的具体要求进行调整。
