坐骨神经损伤模型的量化研究

Quantitative Study on Model of Sciatic Nerve Injury

目的:对SD大鼠坐骨神经钳夹伤模型进行量化研究,确定不同压力对坐骨神经造成的损伤程度,建立符合SunderlandⅤ度分类法中坐骨神经损伤模型。方法:对JZ06Cr 14 cm止血钳进行压力测定,采用JZ06Cr 14 cm止血钳进行造模,将32只4周龄健康清洁级雄性SD大鼠随机分为4组,正常对照组(8只)及压力组(1扣压力亚组、2扣压力亚组、3扣压力亚组各8只),分别于造模后30 min检测各组神经传导速度(NCV),并取神经进行HE染色观察。结果:止血钳压力测定显示止血钳1扣压力约16 N,2扣压力约为31 N,3扣压力约为46 N。1扣压力亚组的坐骨神经传导速度与正常对照组相比差异有统计学意义(P<0.05),形态学显示神经纤维平行排列,结构致密,轴突、髓鞘、神经内膜束膜都完好无破裂;2扣压力亚组的NCV与正常对照组、1扣压力亚组之间相比差异均有统计学意义(P<0.05),形态学可见神经纤维断裂,神经内膜发生部分损害,结构紊乱;3扣压力亚组的部分NCV无法测出,并与其他各组之间差异均有统计学意义(P<0.05),形态学可见神经纤维断裂,神经外膜与束膜均保持完整。结论:约16 N压力坐骨神经钳夹伤模型符合SunderlandⅠ度损伤;约31 N压力坐骨神经钳夹伤模型符合SunderlandⅡ或Ⅲ度损伤;约46 N压力坐骨神经钳夹伤模型符合SunderlandⅢ度损伤。

Objective:To perform a quantitative study to determine the degree of sciatic nerve injury in SD rats caused by varying clamp forces and established a new model of sciatic nerve injury in accordance with the SunderlandⅤclassification.Methods:A force measurement was performed on JZ06Cr 14 cm hemostatic forceps.JZ06Cr 14 cm hemostatic forceps were used in rat model generation.Thirty-two 4-week-old healthy clean-grade male SD rats were randomly divided into groups control(n=8)and pressure[n=32,including hemostatic forceps first ratchet position subgroup(8 rats),second ratchet position subgroup(8 rats),and third ratchet position subgroup(8 rats)].All groups were measured for nerve conduction velocity(NCV)30 minutes after modeling,and the nerves were obtained for HE staining and observation.Results:Force measurements of JZ06cr 14 cm hemostatic forceps showed that the force generated by the first ratchet position was approximately 16 N,that of the second ratchet position was approximately 31 N,and that of the third ratchet position was approximately 46 N.Sciatic nerve NCV of the first ratchet position group showed significant difference compared to that of the control group(P<0.05).Examination of morphology showed nerve fibers arranged in parallel;dense structure;and intact axons,myelin sheaths,and endomembrane without rupture.Sciatic nerve NCV of the second ratchet position group showed significant difference when compared to that of the control group and first ratchet position group(P<0.05).Morphologically,the nerve fibers were broken,the endomembrane partially damaged,and the structure disordered.In the third ratchet position group,the NCV of some nerves could not be measured,and there was statistical significance compared to all other groups(P<0.05).Observation of morphology revealed broken nerve fibers and intact epineurium and perineurium.Conclusion:Approximately 16 N of clamp force creates the sciatic nerve clamp injury model in accordance with SunderlandⅠdegree injury;approximately 31 N accords with SunderlandⅡorⅢdegree injury,and approximately 46 N accords with SunderlandⅢdegree injury.