Department of Orthopedic Surgery, The Third Affiliated Hospital of Xi'an Jiaotong University (Shaanxi Provincial People's Hospital), Xi'an, China.
Department of Gastroenterology, The Third Affiliated Hospital of Xi'an Jiaotong University (Shaanxi Provincial People's Hospital), Xi'an, China.
Eur Spine J. 2020 Mar;29(3):616-627. doi: 10.1007/s00586-019-06268-8. Epub 2020 Jan 1.
To determine the safe range of shortening the spinal column at middle thoracic spine and to observe the changes in blood-spinal cord barrier (BSCB), microglia/macrophage activation and inducible nitric oxide synthase (iNOS) activity after shortening-induced spinal cord injury.
Dogs were allocated to four groups. Group A (control) underwent laminectomy of T7 without shortening the spinal column. Groups B, C and D had 1/3, 1/2, and 2/3 of T7 resected, respectively, followed by spinal shortening. Somatosensory evoked potential (SSEP) and hind-limb function were recorded periodically for 14 days after operation. Spinal cord blood flow (SCBF) and BSCB were detected at the acute phase of shortening. Microglia/macrophage reactions and iNOS activity were observed by immunohistochemistry.
Shortening of 1/3 of a vertebral height caused no significant changes in SSEP and hind-limb function after operation, whereas shortening of 1/2 of the height caused SSEP abnormality and paraparesis, and severe neurologic deficit of hind-limb was observed when the shortening reached 2/3 of the height. SCBF increased temporarily and showed a trend of recovery when the shortening was within 1/2 of a vertebral segment height. When it reached 1/2 or 2/3 of the height, SCBF at 6 h post-operation was 86.33% or 74.95% of the baseline, and an increasing BSCB permeability was observed. In the subsequent 7 days, obvious activation of macrophage and increased number of iNOS-positive cells were observed.
It is safe to shorten the spinal cord within 1/3 of a vertebral height in middle thoracic spine under two-segment laminectomy in canine. The BSCB disruption, macrophage activation, and increased iNOS activity were observed in the acute phase of the injury. These slides can be retrieved under Electronic Supplementary Material.
确定胸椎中段缩短脊柱的安全范围，并观察缩短诱导脊髓损伤后血脊髓屏障（BSCB）、小胶质细胞/巨噬细胞激活和诱导型一氧化氮合酶（iNOS）活性的变化。
狗被分为四组。A 组（对照组）行 T7 椎板切除术但不缩短脊柱。B、C 和 D 组分别切除 1/3、1/2 和 2/3 的 T7 后行脊柱缩短。术后定期记录体感诱发电位（SSEP）和后肢功能 14 天。在缩短的急性期检测脊髓血流（SCBF）和 BSCB。通过免疫组织化学观察小胶质细胞/巨噬细胞反应和 iNOS 活性。
缩短 1/3 个椎体高度术后 SSEP 和后肢功能无明显变化，缩短 1/2 个椎体高度引起 SSEP 异常和截瘫，缩短 2/3 个椎体高度时后肢严重神经功能缺损。SCBF 在缩短至 1/2 个椎体节段高度内时暂时增加并呈恢复趋势。当达到 1/2 或 2/3 的高度时，术后 6 小时的 SCBF 为基线的 86.33%或 74.95%，并且观察到 BSCB 通透性增加。在随后的 7 天中，观察到巨噬细胞明显激活和 iNOS 阳性细胞增多。
在犬双节段椎板切除术中，缩短胸椎中段 1/3 的脊柱是安全的。在损伤的急性期观察到 BSCB 破坏、巨噬细胞激活和 iNOS 活性增加。这些幻灯片可以在电子补充材料中检索到。
