Department of Orthopaedic Surgery, Fukuoka University, Fukuoka, Japan.
Spine (Phila Pa 1976). 2011 Jan 1;36(1):57-62. doi: 10.1097/BRS.0b013e3181ccb1d4.
A total of 15 patients with lumbar disc herniation at the L5-S1 disc level who underwent microendoscopic discectomy were examined. The nerve root blood flow and electrophysiological values were measured during an intraoperative straight-leg-raising (SLR) test.
To investigate the relationships between nerve root blood flow changes and the electrophysiological values during an intraoperative SLR test.
It is unknown how the electrophysiological values are affected by nerve root blood flow changes during an SLR test.
We measured S1 nerve root blood flow and electrophysiologically evaluated the nerve root using the compound muscle action potentials (CMAPs) from the gastrocnemius muscle after S1 nerve root stimulation during an intraoperative SLR test. Subsequently, we analyzed the relationships between the nerve root blood flow changes and the electrophysiological values.
Before discectomy, there were sharp decreases in the nerve root blood flow after 1 and 3 minutes of the SLR test (P < 0.001), and the amplitudes of the CMAPs deteriorated significantly (P < 0.001). Significant correlations were found between the decrease ratio for the nerve root blood flow during the SLR test and the deterioration ratio for the amplitude of the CMAPs. After discectomy, the blood flow increased significantly (P = 0.001). When the SLR test was performed again, the blood flow showed no significant decreases. The average amplitudes of the CMAPs were significantly ameliorated (P < 0.01). When the SLR test was performed again, no significant differences were found for the average amplitudes after 1 and 3 minutes of the test.
Significant correlations were found between the decrease ratio for the nerve root blood flow and the deterioration ratio for the amplitude of the CMAPs. The present results demonstrate that temporary ischemic changes in the nerve root cause transient conduction disturbances.
共对 15 例 L5-S1 椎间盘水平腰椎间盘突出症患者进行了研究，所有患者均行微创经皮内镜椎间盘切除术。术中直腿抬高（SLR）试验时测量神经根血流和电生理值。
探讨术中 SLR 试验时神经根血流变化与电生理值的关系。
目前尚不清楚 SLR 试验时神经根血流变化如何影响电生理值。
术中 SLR 试验时，我们通过刺激 S1 神经根后测量腓肠肌的复合肌肉动作电位（CMAP）来测量 S1 神经根血流并从电生理角度评估神经根，随后分析神经根血流变化与电生理值之间的关系。
在椎间盘切除术前，SLR 试验 1 分钟和 3 分钟后神经根血流明显下降（P < 0.001），CMAP 波幅明显恶化（P < 0.001）。SLR 试验中神经根血流下降率与 CMAP 波幅恶化率之间存在显著相关性。椎间盘切除术后，血流明显增加（P = 0.001）。再次进行 SLR 试验时，血流无明显下降，CMAP 波幅平均明显改善（P < 0.01）。再次进行 SLR 试验时，试验 1 分钟和 3 分钟后 CMAP 波幅的平均振幅无显著差异。
神经根血流下降率与 CMAP 波幅恶化率之间存在显著相关性。本研究结果表明，神经根的短暂缺血性变化可导致短暂的传导障碍。
