体外冲击波对狗胸腰段脊髓神经功能的影响

The effects of extracorporeal shock waves on the lumbar spinal cord

目的探讨体外冲击波(ESW)对狗脊髓神经功能的影响,为腰椎小关节退变所致慢性腰痛的ESW治疗提供理论依据。方法选择5只成年狗,ESW聚焦于L_(4-5)右侧小关节突处,能量设定为14.2 kV,冲击次数为1000次,冲击频率为120次/min。ESW处理前及处理后3 d检测狗双侧后肢体感诱发电位,观察其运动功能变化,取L_(4-5)节段处脊髓标本行病理学检查,同时取T_1节段正常脊髓作为对照观察。结果ESW处理后3 d,狗右后肢Tarlov评分3.5分,左后肢Tarlov评分5分;双侧后肢体感诱发电位检测显示,P波潜伏期延长,P-N波幅下降,左、右后肢P波潜伏期与P-N波幅比较,差异有统计学意义(P<0.05);ESW作用部位的脊髓轻度肿胀,表面静脉充血;镜下可观察到少许红细胞及中性粒细胞渗出,髓鞘轻度肿胀,无脱髓鞘现象。结论ESW对脊髓神经传导功能有影响,脊髓对ESW有一定的耐受能力,至于ESW对脊髓作用的安全距离和能量范围尚需进一步研究。

Objective： To investigate whether or not extracorporeal shock wave （ESW） treatment is safe for treating low back pain caused by lumbar facet joint degeneration by observing its effects on the lumbar segment of the spinal cord. Methods： Five adult dogs were used for this study. ESWs were focused on their right L4_5 facet joints. The energy output was set at 40% of the maximum output, and a total of 1000 shocks were delivered at a frequency of 120/min. Before and 3 days after the treatment, the somatosensory evoked potentials （SEPs） induced by stimulating the tibial nerve were recorded from the animals＇ scalps, and the motor function of their hind limbs was evaluated with Tarlov＇s scale. The animals were then sacrificed and the L4-5 segments of their spinal cords were taken for histopathological observation, with the T12 segments taken as controls. Results Three days after ESW treatment, the left and the right hind limbs scored 5 and 4 on the Tarlov scale. The amplitude of SEPs decreased and their latency increased. Histopathological observation showed mild swelling of the L4_5 segment of the spinal cord with congested veins on the surface. Erythrocyte and leukocyte exudation as well as myelin sheath swelling in the spinal cord were also observed under the microscope, but with no demyelination. Conclusion： ESW had some adverse effects on the spinal cord when focused on the facet joint. Further studies of the safety range of ESW energy and distance are needed.