Ikai T
Department of Orthopaedic Surgery, School of Medicine, Keio University, Tokyo, Japan.
Nihon Seikeigeka Gakkai Zasshi. 1993 Apr;67(4):275-88.
This study attempts clarify the mechanism of neurological deficits in tethered cord syndrome using evoked spinal cord potentials (ESCPs). ESCPs in response to both sciatic nerve (SN-ESCP) and spinal cord stimulation (SC-DESCP) were recorded from the dorsal epidural space. With a fixed degree of caudal traction on the spinal cord in ten cats for 2-4 hours, ESCPs were increased in amplitude in the N1 and N2 deflections of the SC-DESCPs to 158% and 154% at L5 and decreased to 91% and 76% after transient augmentation at L3. On the other hand, the amplitude in the N1 deflection of the SN-ESCPs at L3 and L5 was decreased to 40% and 68%. These findings suggest that not only the force but also the duration of traction influence the degree of the spinal cord dysfunction. When the spinal cords of 17 cats received compression with traction and without traction, the SN-ESCPs of the former became positive earlier than that of the latter. The extent of the recovery in amplitude of both SC-DESCPs and SN-ESCPs propagated over compression site was far limited in the former than in the latter. These results would indicate that the spinal cord subjected to traction is vulnerable to compression.
本研究试图利用脊髓诱发电位（ESCPs）阐明脊髓栓系综合征中神经功能缺损的机制。从硬脊膜外间隙记录坐骨神经（SN - ESCP）和脊髓刺激（SC - DESCP）诱发的ESCPs。对10只猫的脊髓施加固定程度的尾端牵引2 - 4小时，SC - DESCPs的N1和N2波幅在L5处分别增加到158%和154%，在L3处短暂增加后分别降至91%和76%。另一方面，L3和L5处SN - ESCPs的N1波幅分别降至40%和68%。这些发现表明，不仅牵引的力量，而且牵引的持续时间都会影响脊髓功能障碍的程度。当17只猫的脊髓在有牵引和无牵引的情况下受到压迫时，前者的SN - ESCPs比后者更早变为阳性。在前者中，通过压迫部位传播的SC - DESCPs和SN - ESCPs波幅恢复的程度远低于后者。这些结果表明，受到牵引的脊髓更容易受到压迫。
