兔脊髓损伤后脊髓运动诱发电位D波与后肢运动功能的关系

目的 探讨兔脊髓损伤模型损伤后双后肢肌力和脊髓运动诱发电位D波之间的关系.方法 45只兔按随机数字表法分为打击组(显露硬脊膜并打击,并按打击能量大小分为50gcf组、75 gcf组、100gcf组、125 gcf组、150gcf组、175 gcf组、200 gcf组、250 gcf组)和对照组(显露硬脊膜但不打击).打击后和第4周末记录兔双后肢肌力、运动诱发电位D波的潜伏期和波幅,并在第4周末取家兔脊髓行神经微丝(NF)免疫组化染色及病理形态观察,测量NF吸光度值.结果 脊髓损伤当时和第4周末脊髓硬膜外运动诱发电位D波波幅下降的幅度与兔后肢运动功能呈线性相关关系(R2=0.98,P＜0.001,回归曲线Y=0.33+4.82X;R2=0.99,P＜0.001,回归曲线Y=0.04+0.51X),而D波潜伏期的变化则与术后肌力的变化无相关关系(R2=-0097,P=0.573;R2=-0.165,P=0.337);NF吸光度值随着D波波幅的下降而下降,两者呈线性相关关系(R2=0.87,P＜0.001,回归曲线Y=0.12+0.58X).结论 在脊髓损伤中可以通过脊髓硬膜外运动诱发电位D波波幅的下降程度作为判断脊髓损伤运动功能障碍程度的指标.

Abstract：

Objective To study the relationship between D-wave of thc spinal motor evoked potential and hindlimb motor function status (myodynamia) of rabbits with experimental spinal cord injury. Methods Forty-five rabbits were randomly divided into a control group and 8 injured groups (receiving Allen's injury of50, 75, 100, 125, 150, 175, 200 and 250 gcf, respectively). The myodynamia of hindlimbs and the latency and amplitude of D-wave of the spinal motor evoked potential were recorded right after the injury and in the 4th week of injury, respectively. Simultaneously in the 4th week of injury,the rabbits' spinal sections were stained with neurofilament (NF) immunohistochemistry and their pathological morphologies were observed; and optical densities of NF were measured. Statistic analysis of correlation between myodynamia of hindlimbs and latency and amplitude of D-wave was performed.Results A statistic linear correlation was found between amplitudes declination of D-wave of the spinal motor evoked potential and modified Tarlov's scores right after the injury and in the 4th week of injury (R2=0.98, P＜0.00, regression curve: Y=0.33+4.82X; R=0.99, P＜0.001, regression curve: Y=0.04+0.5 1X),but no statistical correlation was noted between myodynamia and the latency of D-wave of the spinal motor evoked potential at the same time periods(R2=-0.097, P=0.573; R2=-0.165, P=0.337). And the optical density of NF decreased following the amplitude declination of D-wave of the spinal motor evoked potential with linear correlation (R2=0.87, P＜0.001, regression curve: Y= 0.12+0.58X).Conclusion Amplitude declination of D-wave of the spinal motor evoked potential could be used to evaluate the severity of dyskinesia in the injured spinal cord.

Relationship between D-wave of the spinal motor evoked potential and hindlimb motor function status of rabbits with experimental spinal cord injury

Objective To study the relationship between D-wave of thc spinal motor evoked potential and hindlimb motor function status (myodynamia) of rabbits with experimental spinal cord injury. Methods Forty-five rabbits were randomly divided into a control group and 8 injured groups (receiving Allen's injury of50, 75, 100, 125, 150, 175, 200 and 250 gcf, respectively). The myodynamia of hindlimbs and the latency and amplitude of D-wave of the spinal motor evoked potential were recorded right after the injury and in the 4th week of injury, respectively. Simultaneously in the 4th week of injury,the rabbits' spinal sections were stained with neurofilament (NF) immunohistochemistry and their pathological morphologies were observed; and optical densities of NF were measured. Statistic analysis of correlation between myodynamia of hindlimbs and latency and amplitude of D-wave was performed.Results A statistic linear correlation was found between amplitudes declination of D-wave of the spinal motor evoked potential and modified Tarlov's scores right after the injury and in the 4th week of injury (R2=0.98, P＜0.00, regression curve: Y=0.33+4.82X; R=0.99, P＜0.001, regression curve: Y=0.04+0.5 1X),but no statistical correlation was noted between myodynamia and the latency of D-wave of the spinal motor evoked potential at the same time periods(R2=-0.097, P=0.573; R2=-0.165, P=0.337). And the optical density of NF decreased following the amplitude declination of D-wave of the spinal motor evoked potential with linear correlation (R2=0.87, P＜0.001, regression curve: Y= 0.12+0.58X).Conclusion Amplitude declination of D-wave of the spinal motor evoked potential could be used to evaluate the severity of dyskinesia in the injured spinal cord.