几丁糖膜预防椎板切除术后硬膜周围粘连的实验研究

目的：观察几丁糖膜对预防椎板切除术后硬膜周围粘连的作用。方法：２４只成年新西兰白兔Ｌ３、Ｌ５水平切除椎板１０×０５ｃｍ,Ｌ３硬膜外放置几丁糖膜（Ａ点）,Ｌ５作为空白对照（Ｂ点）。分别于术后３周、６周、１２周进行大体形态、组织学观察。结果：Ａ点硬膜与瘢痕无明显粘连,硬膜外有空隙,未见明显异物、炎症反应;Ｂ点硬膜与瘢痕紧密粘连,瘢痕侵入椎管内,对硬膜有压迫。结论：几丁糖膜具有明显的预防硬膜周围粘连的作用。     

椎板切除术后预防硬膜外瘢痕粘连的实验研究

为了寻找预防椎板切除后硬膜粘连的材料，选用家兔３０只，随机分为三组，每组１０只。每只作Ｌ３、Ｌ５椎板切除，形成两个大小１ｃｍ×０．５ｃｍ的缺损，一个缺损无任何覆盖，作空白对照；另一个缺损分别在硬膜外覆盖几丁糖、聚乳酸（ＰＬＡ）膜及明胶海绵，即为几丁糖组、ＰＬＡ膜组及明胶海绵组。术后２，４，６，８及１０周处死动物，通过肉眼、光镜及透射电镜，观察瘢痕生长及硬膜外粘连情况。结果表明，几丁糖组和ＰＬＡ膜组硬膜外均光滑、无增厚，硬膜外腔隙未见纤维组织增生或粘连；几丁糖具有明显抑制成纤维细胞生长和促进表皮细胞生长的作用，切口愈合快。而各组空白对照和明胶海绵组硬膜外纤维组织增生或粘连明显，硬膜外腔隙基本消失。认为，可生物降解吸收的几丁糖、ＰＬＡ膜能有效地预防椎板切除术后瘢痕粘连。     

预防椎板切除术后硬膜外粘连的实验研究

目的通过动物实验观察预防硬膜外粘连的有效材料和方法。方法５６只大白兔随机分为４组。切除Ｌ５椎板后造成１２ｍｍ×５ｍｍ硬脊膜裸露区,Ａ组不用任何间置物覆盖,Ｂ组充填质量分数为２％的透明质酸钠,Ｃ组用酒精保存的异体硬脊膜覆盖,Ｄ组用透明质酸钠充填后再用硬脊膜覆盖。术后２、４、８、１２周进行肉眼及光镜观察,８周还行硬膜外粘连等级评定及计算机图像分析。结果Ａ组硬膜外形成致密粘连,Ｂ、Ｃ组部分粘连,Ｄ组无明显粘连。结论保存硬脊膜与透明质酸钠联合应用为预防椎管内粘连最为有效的方法。     

防硬膜外粘连的实验研究与临床观察

目的：观察椎板切除术后防止硬膜外瘢痕粘连的几种物质及其作用机制。方法：用４８只ＳＤ大鼠制作硬膜外损伤模型，在损伤的硬膜表面涂布透明质酸钠、自体游离脂肪、几丁糖、生理盐水，分别于术后４、８、１２周观察瘢痕形成情况并测定胶原纤维含量。椎板切除术中临床上用不同防粘连方法共１８８例。分３组，即Ａ组硬膜外未做任何防粘连处理共１５例。Ｂ组硬膜外涂布几丁糖以防粘连共６４例。Ｃ组为硬膜外涂布几丁糖的同时加自体硬膜外带血供脂肪覆盖共１０９例。术后半年进行功能评定和ＭＲＩ检查。结果：生理盐水组大鼠硬膜外瘢痕自第４周开始形成，于第８周达高峰，１２周时开始软化、收缩。透明质酸钠与几丁糖预防瘢痕形成均有明显效果，其中几丁糖明显优于透明质酸钠。组织相容性自体游离脂肪最好，其次是几丁糖、透明质酸钠。临床结果Ｃ组为最佳防粘连方法，Ｂ组其次，Ａ组明显差于上述两组。结论：几丁糖对硬膜外周围的瘢痕形成、粘连有明显预防作用。     

预防椎板切除术后硬膜外疤痕粘连的实验研究

对１０只山羊在暴露的硬膜表面分别行不相连续的椎板切除术。Ｌ_２～３水平为空白对照（Ｃ点），Ｌ_４～５水平涂硅油（Ｂ点），Ｌ_６～Ｓ_１水平涂硅油阿霉素油剂（Ａ）点。术后动态观察１６周脊柱横断面变化，显示Ａ、Ｂ两点疤痕与硬膜均无粘连，Ｃ点则紧密粘连。与Ｂ、Ｃ两点比较，Ａ点各期疤痕均薄，成熟晚。结果表明：医用２０１甲基硅油能有效地预防硬膜与疤痕粘连，对机体无毒、无副作用。阿霉素可减少疤痕生成，延缓疤痕成熟，但对神经可产生毒性或刺激作用。     

聚乙交酯膜预防椎管术后硬膜外瘢痕粘连的实验研究-大体组织学改变

目的观察聚乙交酯(PGA)膜对预防椎板切除术后硬膜周围粘连的作用.方法在新西兰兔L3、L5部位切除椎板1.0cm×0.5cm,一缺损处在硬膜外放置PGA膜,另一缺损部放置明胶海绵或空白对照,于术后3、6、9、12周作形态和组织学观察.结果大体形态观察PGA膜3周时开始降解,6周时分解成较大碎片,9周时吸收60%～80%,12周时仅残留部分小碎片,硬膜外无瘢痕粘连.明胶海绵和空白对照组瘢痕粘连发生率为88%和100%.组织学检查PGA膜组各时点均未见硬膜外纤维组织产生,硬膜与背侧组织无粘连,明胶海绵组(除3周外)和空白对照组均产生明显的粘连.结论PGA膜能有效防止椎管术后瘢痕粘连.     

预防硬膜外瘢痕粘连的实验研究

目的通过动物实验观察几丁糖对预防椎板切除术后硬膜瘢痕粘连的作用。方法24只成年山羊行腰2腰4短节段椎弓根钉系统固定及取自体髂骨行后外侧植骨融合术,腰3水平全椎板切除,切除口约3cm×1.5cm,腰3硬膜外分别放置几丁糖或空白对照各12只。于术后24周进行大体形态、组织学观察,并进行硬膜外瘢痕粘连程度分级。结果几丁糖组硬膜与瘢痕无明显粘连,空白对照组硬膜与瘢痕紧密粘连。结论几丁糖能有效地预防椎板切除术后硬膜外瘢痕粘连。     

不同材料预防椎板切除后硬膜粘连的实验研究

为观察不同材料对椎板切除后硬膜粘连的预防效果，作者以１４４只ＳＤ大鼠为实验对象，研究了聚合纤维素（ＰＣＭＣ）、透明质酸钠（ＳＨＡ）、明胶海绵（ＧＦ）、棘上韧带（Ｌ）和游离脂肪（ＦＦ）在预防椎板切除后硬膜周围粘连中的作用。通过肉眼、光镜、电镜观察，计算机图像分析，增强ＭＲＩ扫描观察。结果显示：椎板切除后硬膜周围粘连的高峰在术后８周内。ＰＣＭＣ作为三维的屏障材料能有效地防止硬膜的粘连。ＳＨＡ早期防止粘连有一定作用，晚期作用不明显。明胶海绵和棘上韧带防粘连无效。ＦＦ虽可防止硬膜的粘连，但感染率高，脂肪萎缩与坏死严重，晚期几乎均不同程度地向椎管内嵌入，甚至造成脊髓和神经根受压。     

几丁糖防硬膜外粘连的实验与临床研究

目的 观察选择性脊神经后根切除术（ＳＰＲ）椎板切除术后硬膜几种防瘢痕粘连物质的作用及其机制。方法 用４８只ＳＤ大鼠制作硬膜外周围粘连模型,在损伤的硬膜表面涂布透明质酸钠,自体游离脂肪,几丁糖,生理盐水,分别于４,８,１２周观察瘢痕形成情况并测定胶原纤维含量。ＳＰＲ术后临床上用不同防粘连方法共２１６例,分４组即Ａ组硬膜外未作任何防粘连措施１５例,Ｂ组硬膜外涂布几丁糖作防粘连６４例Ｃ组为硬膜外涂布几丁     

大鼠是否适合作椎板切除后硬膜粘连的实验模型?

有些学者以大鼠为实验对象进行椎板切除后硬膜外瘢痕形成与粘连的实验研究[1～ 3] 。由于低级动物椎板有再生能力 ,且速度较快 ,这无疑会影响预防效果观察的准确性。作者对大鼠是否适合作椎板切除后防止硬膜粘连的实验模型作了观察。材料与方法　成年ＳＤ大鼠 2 4只 ,体重 2 0 0～ 2 5 0 ｇ ,雌雄各半。随机分为黄韧带保留完整组和黄韧带部分切除组 ,各 12只。 1%戊巴比妥 ( 2 5ｍｇ/ｋｇ)大鼠腹腔注射麻醉。取腰背正中切口3ｃｍ ,剥离骶棘肌 ,剪去Ｌ1、Ｌ2 棘突 ,用特制微型咬骨钳咬除椎板 ,造成 0 2×1 0ｃｍ椎板缺损。一组保留完整的黄…     

Prevention of postlaminectomy scar formation

An animal experimental study was performed to investigate prevention of scar formation under lumbar laminectomy by using new biodegradable interposing materials-- polylactic acid (PLA) foam and membrane. The experimental animals consisted of 32 dogs, 16 control and 16 experimental. The experimental surgery consisted of L5 or L6 complete laminectomy and covering of the laminectomy defect with the experimental materials. The same procedure but without the covering of the laminectomy defect was performed on the control group animals. Animals were sacrificed at varying intervals (2-52 weeks) and the lumbar spines were evaluated with histologic preparations. The PLA membrane is found to be a promising material for prevention of scar tissue extension and adhesion after laminectomy but has a problem of marginal fitting. PLA foam is found to behave as a scaffold for scar tissue extension and adhesion onto the nerve. Other foamy materials such as gelatin foam or avitane are probably behaving similarly, causing scar tissue extension and adhesion. The new materials were found to be completely biocompatible and slowly biodegradable. A combined use of posteriorly convexed stiff PLA membrane and marginal gap filler with PLA foam may provide solutions for both prevention of scar tissue extension and adhesion and prevention of postlaminectomy spinal stenosis.     

防止椎板切除术后硬脊膜外瘢痕粘连的实验研究

作者在４个平面间隔切除１１只山羊的椎板，分别用硅胶膜、自体游离脂肪片、带蒂肌肉瓣覆盖硬脊膜，一处平面作空白对照。术后４个月组织学检查，结果显示，硅胶膜后方有少许瘢痕组织增生，间质中有炎细胞灶状浸润，硅胶膜与硬膜囊无瘢痕形成，新形成的椎管后壁光滑，硬膜囊无受压；脂肪片被纤维组织取代，周围纤维组织增生轻微，形成菲薄之纤维膜，与硬脊膜容易分离；带蒂肌肉瓣周围形成较多瘢痕与硬脊膜粘连重，肌肉瓣已完全纤维化，空白组形成瘢痕最多，与硬脊膜粘连最重。术后硬膜囊矢状径以硅胶膜组最大，脂肪片组次之，带蒂肌肉瓣组再次之，空白组最小。作者认为，硅胶膜与脂肪片能明显防止椎板切除术后纤维瘢痕粘连对硬膜囊的压迫，在支架诱导作用方面，硅胶膜优于脂肪片，在生物相容性方面脂肪片优于硅胶膜。带蒂肌肉瓣优于对照组，但不及前两者。     

聚乳酸凝胶预防硬膜外瘢痕粘连的实验研究

目的 探讨新型生物可吸收材料聚乳酸凝胶(polyactic acid glue，PLA-G)预防椎板切除术后硬膜外瘢痕粘连的作用。方法 切除24只成年日本大耳白兔的L2和L5椎板；在L5外露的硬膜及神经根表面喷涂液态PLA-G形成胶冻膜，为实验组；L2处只做椎板切除，为自身空白对照组。术后2、4、6、8、10及12周随机处死各4只兔，取标本行大体、组织学及超微结构的观察。结果 2周时实验组PLA-G未降解为机械屏障膜，硬膜与外侧瘢痕组织(scartissue，ST)间有明显间隙，光镜下显示间隙内无细胞；对照组为血肿覆盖较易分开，硬膜与ST间有血细胞团块，成纤维细胞(fibroblast，FB)增生活跃。4周时实验组PLA-G部分降解，机械屏障及间隙存在，光镜下ST中FB增多；对照组为较多质脆ST与硬膜广泛粘连，光镜下可见组织细胞浸润间隙，ST内FB明显多于实验组。6周时实验组PLA-G完全降解，少量ST与硬膜无粘连，光镜下FB已减少；对照组有大量质韧难以从硬膜分离的ST，FB继续增生活跃。8、10及12周时实验组ST与硬膜无粘连；对照组ST与硬膜粘连严重，光镜下见ST和硬膜粘连紧密伴毛细血管再造。超微结构观察：4周时实验组FB的粗面内质网较稀疏，分泌胶原纤维少；对照组FB的粗面内质网极丰富，胶原纤维多而成束。结论 PLA-G在实验兔腰椎板切除后的硬膜外能有效地减少瘢痕形成和粘连。     

Effect of polylactic acid glue in preventing epidural scar mdhesion after laminectomy in rabbits

Objective： To determine the efficacy of polylactic acid glue in preventing epidural scar adhesion after laminectomy in rabbits. Methods： Twenty-four Japanese white rabbits underwent laminectomy （including the attached ligaments） at Lz and Ls. After laminectomy at Ls, polylactic acid glue was sprayed on the dura and nerve roots and this segment was taken as the experimental group. After laminectomy at Lz, nothing was used and this segment was enrolled as the self control group. Four rabbits were killed every two weeks postoperatively till the end of the experiment at 12 weeks. Then the operated spine was observed grossly, histologically and ultrastructurally to check the degree of scar formation, the status of epidural scar adhesion, the absorption of the glue, and the intraceHular structure of fibroblasts. Results： The glue coagulated immediately after spraying and showed excellent hemostatic effect. The glue membrane was easy to be taken away from the dura mater of the samples for 2 weeks and there were no cells in the epidural space in the experimental group. But the dura mater was covered by hematoma in the control group,which formed mild adhesion, with fibroblasts proliferating actively. In the 4th week, some glue shivers remained in the epidural space with fibroblasts increasing a little, and the dura mater was smooth in the experimental group. However, in the control group, the formed scar was fragile and conglutinated with the dura mater diffusely and fibroblasts were much more than those in the experimental group. In the 6th-12th weeks, there was a potential interspace between the scar and the dura mater, and the polylactic acid glue was absorbed completely in the experimental group. Much tough scar was found in the control group, which was very difficult to dissect from the dura mater and the surrounding tissues. From the ultrastructural observation of the fibroblasts, the nucleus became much bigger and the rough endoplasmic reticulum was much more plentiful in the control group than that in the experimental group. Conclusions： Polylactic acid glue can effectively reduce epidural cicatrization and adhesion.     

Effect of polylactic acid glue in preventing epidural scar adhesion after laminectomy in rabbits

Objective: To determine the efficacy of polylactic acid glue in preventing epidural scar adhesion after laminectomy in rabbits. Methods: Twenty-four Japanese white rabbits underwent laminectomy (including the attached ligaments) at L2 and L5. After laminectomy at L5, polylactic acid glue was sprayed on the dura and nerve roots and this segment was taken as the experimental group. After laminectomy at L2, nothing was used and this segment was enrolled as the self control group. Four rabbits were killed every two weeks postoperatively till the end of the experiment at 12 weeks. Then the operated spine was observed grossly, histologically and ultrastructurally to check the degree of scar formation, the status of epidural scar adhesion, the absorption of the glue, and the intracellular structure of fibroblasts. Results: The glue coagulated immediately after spraying and showed excellent hemostatic effect. The glue membrane was easy to be taken away from the dura mater of the samples for 2 weeks and there were no cells in the epidural space in the experimental group. But the dura mater was covered by hematoma in the control group, which formed mild adhesion, with fibroblasts proliferating actively. In the 4th week, some glue shivers remained in the epidural space with fibroblasts increasing a little, and the dura mater was smooth in the experimental group. However, in the control group, the formed scar was fragile and conglutinated with the dura mater diffusely and fibroblasts were much more than those in the experimental group. In the 6th-12th weeks, there was a potential interspace between the scar and the dura mater, and the polylactic acid glue was absorbed completely in the experimental group. Much tough scar was found in the control group, which was very difficult to dissect from the dura mater and the surrounding tissues. From the ultrastructural observation of the fibroblasts, the nucleus became much bigger and the rough endoplasmic reticulum was much more plentiful in the control group than that in the experimental group. Conclusions: Polylactic acid glue can effectively reduce epidural cicatrization and adhesion.     

选择性脊神经后根切除术椎板切除后硬膜外防粘连的实验研究

目的观察选择性脊神经后根切除术（ＳＰＲ）椎板切除后硬膜外几种防瘢痕粘连物质的作用并探讨其机制。方法用４８只ＳＤ大鼠制作硬膜外周围粘连模型,在损伤的硬膜表面分别涂布透明质酸钠、自体游离脂肪、几丁糖、生理盐水,分别于４、８、１２周观察瘢痕形成情况并测定胶原纤维含量。结果生理盐水组大鼠硬膜外瘢痕自第４周开始形成,于第８周达高峰,１２周时开始软化、收缩;透明质酸钠与几丁糖预防瘢痕形成均有明显效果,其中几丁糖明显优于透明质酸钠;组织相容性以自体游离脂肪最好,其次是几丁糖、透明质酸钠。结论几丁糖对硬膜外周围瘢痕形成、粘连有明显预防作用     

Vertebral plate regeneration induced by radiation-sterilized aliogeneic bone sheets in sheep

Objective: To evaluate the effects and mechanism of radiation-sterilized allogeneic bone sheets in inducing vertebral plate regeneration after laminectomy in sheep. Methods: Twelve adult male sheep (aged 1.5 years and weighing 27 kg on average) provided by China Institute for Radiation Protection underwent L3-4 and L4-5 laminectomy. Then they were randomly divided into two groups: Group A ( n = 6 ) and Group B ( n = 6 ). The operated sites of L4-5 in Group A and L3-4 in Group B were covered by " H-shaped" freeze-drying and radiation-sterilized allogeneic bone sheets ( the experimental segments), while the operated sites of L3-4 in Group A and L4-5 in Group B were uncovered as the self controls (the control segments ). The regeneration process of the vertebral plate and the adhesion degree of the dura were observed at 4,8,12,16,20 and 24 weeks after operation. X-ray and CT scan were performed in both segments of L3-4 and L4-5 at 4 and 24 weeks after operation. Results: In the experimental segments, the bone sheets were located in the anatomical site of vertebral plate, and no lumbar spinal stenosis or compression of the dura was observed. The bone sheets were absorbed gradually and fused well with the regenerated vertebral plate. While in the control segments, the regeneration of vertebral plate was not completed yet, the scar was inserted into the spinal canal, compressing the dura and the spinal cord, and the epidural area almost disappeared. Compared with the control segments, the dura adhesion degree in the experimental regenerated segments was much milder (P<0.01), the internal volume of the vertebral canal had no obvious change and the shape of the dura sack remained well without obvious compression. Conclusions: Freeze-drying and radiation-sterilized allogeneic bone sheets are ideal materials for extradural laminoplasty due to their good biocompatibility, biomechanical characteristics and osteogenic ability. They can effectively reduce formation of post-laminectomy scars, prevent recurrence of post-laminectomy spinal stenosis, and induce regeneration of vertebral plates.