1Department of Neurological Surgery, University of Washington, Seattle, Washington.
2Faculty of Medicine and University Hospital Cologne, Department of Orthopedics and Trauma Surgery, University of Cologne; and.
J Neurosurg Spine. 2022 Nov 18;38(3):299-306. doi: 10.3171/2022.6.SPINE22383. Print 2023 Mar 1.
Acute traumatic spinal cord injury (tSCI) is followed by a prolonged period of secondary neuroglial cell death. Neuroprotective interventions, such as surgical spinal cord decompression, aim to mitigate secondary injury. In this study, the authors explore whether the effect size of posttraumatic neuroprotective spinal cord decompression varies with injury severity.
Seventy-one adult female Long Evans rats were subjected to a thoracic tSCI using a third-generation spinal contusion device. Moderate and severe tSCI were defined by recorded impact force delivered to the spinal cord. Immediately after injury (< 15 minutes), treatment cohorts underwent either a decompressive durotomy or myelotomy. Functional recovery was documented using the Basso, Beattie, and Bresnahan locomotor scale, and tissue sparing was documented using histological analysis.
Moderate and severe injuries were separated at a cutoff point of 231.8 kdyn peak impact force based on locomotor recovery at 8 weeks after injury. Durotomy improved hindlimb locomotor recovery 8 weeks after moderate trauma (p < 0.01), but not after severe trauma (p > 0.05). Myelotomy led to increased tissue sparing (p < 0.0001) and a significantly higher number of spared motor neurons (p < 0.05) in moderate trauma, but no such effect was noted in severely injured rats (p > 0.05). Within the moderate injury group, myelotomy also resulted in significantly more spared tissue when compared with durotomy-only animals (p < 0.01).
These results suggest that the neuroprotective effects of surgical spinal cord decompression decrease with increasing injury severity in a rodent tSCI model.
急性创伤性脊髓损伤（tSCI）后会经历一段较长时间的继发性神经胶质细胞死亡。神经保护干预措施，如脊髓减压手术，旨在减轻继发性损伤。在这项研究中，作者探讨了创伤后神经保护性脊髓减压的效果大小是否随损伤严重程度而变化。
71 只成年雌性 Long Evans 大鼠使用第三代脊髓挫伤装置造成胸段 tSCI。中度和重度 tSCI 由记录到的脊髓所受冲击力量来定义。损伤后立即（<15 分钟），治疗组进行减压性椎板切开术或椎板切除术。使用 Basso、Beattie 和 Bresnahan 运动评分记录功能恢复情况，使用组织学分析记录组织保留情况。
根据损伤后 8 周的运动恢复情况，将中度和重度损伤在 231.8 kdyn 峰值冲击力的截定点分开。在中度创伤时，椎板切开术改善了后肢运动恢复（p<0.01），但在重度创伤时没有改善（p>0.05）。在中度创伤时，椎板切除术导致更多的组织保留（p<0.0001）和显著更多的存活运动神经元（p<0.05），但在重度损伤的大鼠中没有观察到这种效果（p>0.05）。在中度损伤组中，与单纯椎板切开术动物相比，椎板切除术也导致更多的组织保留（p<0.01）。
这些结果表明，在啮齿动物 tSCI 模型中，手术性脊髓减压的神经保护作用随损伤严重程度的增加而降低。
