Objective To study the clinical effects of artificial vertebral laminae of the biomimetic nano-hydroxyapatite/polyamide 66 (n-HA/PA66) composites in prevention of the scar formation in lumbar spinal canal and the reconstruction of posterior vertebral laminae structure. Methods From January 2003 to December 2005, 23 patients were treated with artificialvertebral laminae of the biomimetic n-HA/PA66 composites. There were 16 males and 7 females, aging from 48 to 76 years with an average of 59 years. Of 23 cases,11 cases had spinal stenosis, 7 cases had spinal stenosis with spondylolysis, 3 cases had lumbar disk herniation and 2 cases had spinal tumor. Twenty cases of vertebral laminae were reconstructed by 1 artificial vertebral laminae and 3 cases by 2.The affected locations were C5,6,L1 and L2 in 1 case respectively; L4,5 in 5 cases; L4-S1 in 9 cases; and L5, S1 in 6 cases. Results First intension was achieved in 22 cases and infection occured in 1 case.In the period of follow-up for all cases lasted from 5 to 24 months,the postoperative CT showed that the nHA/PA66 artificial vertebral laminae enlarged the spinal canal. MRI showed little scar formation and adhesion in the lumbar spinal canal. CT showed illdefined boundary between artificial vertebral laminae and recipient vertebral laminae. No neural symptoms occured in all cases except onebecause of stretch injury of nerve root in operation. Also no rejection reaction was observed. Conclusion The artificial vertebral laminae of the biomimetic nHA/PA66 composites can effectively prevent the compression to the nerve root and dural sac from the scar and restore the vertebral laminae.
Objective To explore effective substances and methods for prevention of peridural adhesion. Methods Laminectomy was performed on the 5th lumbar segment in 64 rabbits, which were equally divided into 4 groups. The duramater (12 mm×6 mm) was exposed. The exposed duramater was left uncovered in Group A; the exposed dura mater was covered with sodium hyaluronate jel (high molecular weight, 1 ml) in Group B; the lamina repair was performed with the autologous spinous process in Group C; the lamina repair was performed with the sodium hyaluronate jel filling and the autologous spinousprocess in Group D. The specimens were observed grossly and histologically at 2, 4, 6 and 8 weeks postoperatively. The computed imaging analysis on the epidural adhesion was also performed at 6 weeks postoperatively. Results ①The gross anatomical evaluation: Severe peridural adhesion was formed in Group A, less adhesion formed in Groups B and C, but no obvious adhesion formed in Group D. ②The area percentage of the epidural scar: The area percentage ofthe epidural scar was 15.89%±1.88% and 13.94%±1.89% in Groups C and D respectively, which were significantly lower than those in Groups A and B (22.66%±2.89% and 20.70%±2.82%,Plt;0.05). ③The density of epidural scar: Thedensity of the epidural scars were 42.03%±7.36% and 36.50%±9.08% in Groups B and D, which were significantly lower than those in Groups A and C (63.73%±6.06% and 52.11%±4.10%，Plt;0.05). Conclusion The high molecular weight sodium hyaluronate jel filling combined with the lamina repair using the autologous spinous process has the best preventive effect on the peridural adhesion after laminectomy.
Objective To study the effect of the allogeneic bone sheet that has been treated by the freezedrying and radiation sterilization in preventing the epidural adhesion after laminectomy in sheep. Methods Laminectomy was performed on L3,4and L4,5 of 12 adult male sheep. Afteroperation, one site of L3,4 or L4,5was covered by the allogeneicbone sheet in “H” shape after the freeze-drying and radiation sterilization treatment; and the other site was used as a control. The sheep were killed and the specimens were retrieved at 4，8，12，16，20 and 24 weeks after operation to observe the scar formation process. X-ray andCT scan were performed in the segments of L3,4and L4,5at 4 and 24weeks. Results Four weeks after operation, the position and the shape of the allogeneic bone sheet were good in condition, and no lumbar spinal stenosis or compression of the dura was found in the experimental sections. Twentyfour weeks after operation theexamination on the experimental sections revealed that the vertebral canal reconstruction was completed, the allograft was absorbed almost completely, and inosculation with the lamina of the vertebra and the shape of the lumbar spine were good, with no fibroid tissues found in the epidural area. Compared with the control segment, the dura adhesion degree in the laminoplasty segment was significantly decreased (Plt;0.01), and the dura sac remained in a good shape. There was no obvious compression on the dura. Conclusion The allogeneic bone sheet after the treatment of freeze-drying and radiation sterilization can effectively reduce the scar formation after laminectomy and prevent postoperative recurrence of the spinal stenosis.
Objective To determine the ability of the polyactic acid glue (PLA-G) in preventing epidural adhesion after laminectomy. Methods Each of the 24 randomly selected rats was done laminectomyof L2 and L5. The PLA-G, which would change from liquid to solid when meets with serum, was used in the epidural site of L5 to become a half-solid membrane(the experimental group, EG). The PLA-G was not used in the same site of L2(the control group, CG) .The gross anatomical, histological, and microscopical evaluation were made 2，4，6，8，10 and 12 weeks after operation; electron microscope observation was also made on two rats 4 weeks after operation(both EG and CG). Results Obvious epidural space was observed between dura mater and scar tissue(ST), but no cells in the epidural space were observed inEG 2 weeks after operation. Corps of the red cells between dura mater and ST and proliferation of fibroblast cell(FB) were observed in CG 2 weeks after operation. Some remaining glue shiver in the epidural space with lightly increasing fibroblast and smooth dura mater were observed in EG 4 weeks after operation. However, fragile scar conglutinated with dura mater diffusely and more FB were observed in CG. From the 6th week to the 12th week, a potential interspace between scar and dura mater was observed and PLA glue was absorbed completely in EG. However, tougher scar, which was very difficult to dissect from dura mater and surrounding tissues, was observed. According to the fibroblast ultrastructure observation, bigger nucleus and more plentiful rough endoplasmic reticulum were observed in CG. Conclusion The PLA-G can effectively reduce the epidural scar and adhesion in animal experiment.
In order to find an ideal biological material to prevent peridural adhesion following laminectomy, 30 rabbits were used as animal model, in each of which 2 defects with a size of 1 cm x 0.5 cm were made following laminectomy of L3, L5 spine. One of the defects was covered extradurally with chitosan, gelatin foam or PLA membrane respectively, while the other defect was exposed as control. All of these animals were sacrificed on the 2nd, 4th, 6th, 8th and 10th week after operation, and the extradural fibrosis and adhesion of every animal were evaluated by gross observation and histological examinations. It was revealed that in the chitosan and PLA membrane groups, the extradural tissue was smooth without thickening and there was no fibrous proliferation or adhesion in the epidural cavity, and that in the chitosan group, the growth of fibroblast was restrained but the growth of the epithelial cells was promoted significantly, thus, wound healing was rapid. In the control group and gelatin foam group, obvious extradural fibrosis and adhesion were observed and the extradural space had almost disappeared. Therefore, it was concluded that the biodegradable PLA membrane and chitosan were both an ideal material in the prevention of postoperative epidural adhesion.
目的 根据MRI颈脊髓信号异常平面决定椎板切除减压范围，观察侧块螺钉固定结合不同范围全椎板切除减压治疗在颈脊髓损伤的临床疗效。 方法 2008年9月-2011年12月收治颈脊髓损伤患者16例。其中男10例，女6例，高处坠落伤5例，车祸11例，MRI显示脊髓损伤信号改变波及2个节段3例，3个节段9例，4个节段4例，椎间盘损伤变性12例，椎间盘轻度突出4例，均诊断为颈脊髓损伤伴高位截瘫，均行后路手术治疗。根据手术方式将16位患者分为观察组（9例）及对照组（7例），均采用后路侧块螺钉固定结合全椎板切除减压治疗，观察组减压范围以MRI提示颈脊髓信号异常为中心，对照组减压范围均为颈3～颈7。比较两组治疗前后的ASIA评分改变。 结果 16例患者均得到随访，随访10～48个月，平均17个月，脊髓神经恢复功能按照ASIA运动评分，平均增长值：对照组（42.75 ± 12.56）高于观察组（20.52 ± 11.60），差异有统计学意义（P＜0.05）。观察组患者ASIA分级分布：术前A级4例，B级4例，C级1例，末次家庭随访时A级4例，B级3例，C级2例；对照组术前A级3例，B级3例，C级1例，末次家庭随访时A级2例，B级1例，C级2例，D级2例，对照组ASIA分级术前与术后比较，差异有统计学意义（P＜0.05）；观察组ASIA分级术前与术后比较，差异无统计学意义（P＞0.05）；比较两组ASIA分级改善率，对照组明显优于观察组（P＜0.05）。 结论 根据MRI提示的颈脊髓信号异常平面决定侧块螺钉固定及颈椎板切除范围治疗颈脊髓损伤疗效不佳，减压范围扩大至颈3-颈7疗效较好。
Objective To investigate the safety and efficacy of different doses of tranexamic acid (TXA) in posterior cervical laminectomy with lateral mass screw fixation and bone graft fusion by a prospective clinical study. Methods The middle-aged and elderly patients with cervical spondylotic myelopathy, who were admitted between January 2020 and January 2022 and scheduled to undergo posterior cervical laminectomy with lateral mass screw fixation and bone graft fusion, were studied as the research subjects. Among them, 165 patients met the selection criteria and were included in the study. The patients were allocated into 3 groups (n=55) by random double-blind lottery. Groups A and B were given intravenous infusion of TXA at 30 minutes before operation according to the standards of 15 and 30 mg/kg, respectively; and group C was given normal saline in the same way. There was no significant difference in gender, age, body mass index, and preoperative D-dimer, hemoglobin (Hb), and hematocrit (HCT) between groups (P>0.05). The intraoperative bleeding, intraoperative blood transfusion, postoperative drainage volume, drainage days, and postoperative hospital stay were recorded. The Hb, HCT, and D-dimer were compared before operation and at 3 days after operation. Venous ultrasonography of the lower extremities was taken after operation to assess thrombosis; and the postoperative hematoma and epilepsy were also observed. Results All operations were successfully completed, and the incisions healed by first intention. The differences in intraoperative bleeding volume, postoperative drainage volume, drainage days, and postoperative hospital stay between groups were significant (P<0.05). The above indexes were significantly less in group B than in groups A and C. During operation, 14 patients in group A and 23 patients in group C were transfused, and no patient in group B had blood transfusions. Compared with groups A and C, the blood transfusion volume in group B significantly decreased (P<0.05), and the difference between groups A and C was not significant (P>0.05). There was no significant difference in the differences of D-dimer, Hb, and HCT before and after operation between groups (P>0.05). At 5 days after operation, the venous ultrasonography of the lower extremities showed that the 2 cases of intermuscular venous thrombosis occurred in groups A, B, and C, respectively. No hematoma or epilepsy occurred after operation. Conclusion The application of 15 and 30 mg/kg TXA in posterior cervical laminectomy with lateral mass screw fixation and bone graft fusion can reduce intraoperative bleeding and postoperative drainage volume, postoperative drainage days, and postoperative hospital stay. And application of 30 mg/kg TXA can reduce intraoperative blood transfusion, without increasing the risk of lower extremity venous thrombosis, hematoma, and epilepsy.