摘要
目的探讨微骨折技术联合仿生水凝胶支架对兔肩袖损伤修补术后腱-骨愈合的影响。方法利用明胶和甲基丙烯酸酐合成甲基丙烯酰胺基明胶,通过紫外光交联和真空冷冻干燥技术制备仿生水凝胶支架。大体观察支架颜色、性状后,扫描电镜观察其微观形貌,并行体外降解性能测试。取24只成年新西兰大白兔,雌雄不限,体质量2.8~3.5 kg,建立双侧急性肩袖损伤模型后,随机取一侧行止点骨床微骨折处理联合穿骨肌腱修补术(对照组,n=24);另一侧在微骨折处理后,将仿生水凝胶支架植入骨床,再行穿骨肌腱修补术(实验组,n=24)。术后观察动物一般情况,分别于术后4、8周取肩袖标本行大体观察、Micro-CT检测、HE染色和生物力学测试。结果仿生水凝胶支架外观呈白色,具有丰富多孔结构,孔径为31.7~89.9μm,于PBS溶液中能缓慢降解,18 d时降解率约为95%。兔肩袖修补术后均存活至实验完成。大体观察示两组腱-骨界面未见明显缺损和再撕裂。Micro-CT检测,术后4、8周两组骨密度、组织骨密度和骨体积分数差异均无统计学意义(P>0.05)。HE染色显示术后4、8周对照组腱-骨界面均以纤维瘢痕组织为主,而实验组术后4周腱-骨界面部分区域可见矿化软骨和纤维软骨形成,且术后8周软骨逐渐呈有序排列成过渡结构;术后4、8周,实验组肌腱成熟度评分均明显优于对照组(P<0.05)。生物力学测试术后4周两组极限负荷和刚度差异无统计学意义(P>0.05);术后8周两组刚度差异无统计学意义(t=2.286,P=0.071),但实验组极限负荷明显优于对照组(t=4.162,P=0.009)。结论与单纯微骨折技术相比,微骨折技术联合仿生水凝胶支架有利于兔肩袖腱-骨愈合,增强腱-骨界面抗拉性能。
Objective To assess the effect of microfracture and biomimetic hydrogel scaffold on tendon-to-bone healing in a rabbit rotator cuff tear model.Methods Gelatin and methacrylic anhydride were used to synthesize gelatin methacryloyl(GelMA).Then the GelMA were treated with ultraviolet rays and vacuum freeze-drying method to obtain a biomimetic hydrogel scaffold.The morphology of the scaffold was observed by gross observation and scanning electron microscope.Degradation of the scaffold was determined at different time points.Twenty-four adult New Zealand rabbits,weighting 2.8-3.5 kg and male or female,were surgically created the bilateral acute rotator cuff tear models.One shoulder was treated with microfractures on the footprint and transosseous suture(control group,n=24).The other shoulder was treated with the same way,except for putting the scaffold on the footprint before transosseous suture(experimental group,n=24).The general conditions of rabbits were observed postoperatively.Tendon-to-bone healing was evaluated by gross observation,Micro-CT,HE staining,and bio-mechanical testing at 4 and 8 weeks after operation.Results The scaffold was white and has a porous structure with pore size of 31.7-89.9μm,which degraded slowly in PBS solution.The degradation rate was about 95%at 18 days.All the rabbits survived to the completion of the experiment.Micro-CT showed that there was no obvious defect and re-tear at the tendon-to-bone interface in both groups.No difference was found in bone mineral density(BMD),tissue mineral density(TMD),and bone volume/total volume(BV/TV)between the two groups at 4 and 8 weeks postoperatively(P>0.05).HE staining showed that the fibrous scar tissue was the main component at the tendon-to-bone interface in the control group at 4 and 8 weeks postoperatively;the disorderly arranged mineralized cartilage and fibrocartilage formation were observed at the tendon-to-bone interface in the experimental group at 4 weeks,and the orderly arranged cartilage formation was observed at 8 weeks.Besides,the tendon maturation scores of the experimental group were significantly higher than those of the control group at 4 and 8 weeks(P<0.05).There was no significant difference in the ultimate load to failure and stiffness between the two groups at 4 weeks(P>0.05);the ultimate load to failure at 8 weeks was significantly higher in the experiment group than in the control group(t=4.162,P=0.009),and no significant difference was found in stiffness between the two groups at 8 weeks(t=2.286,P=0.071).Conclusion Compared with microfracture alone,microfracture combined with biomimetic hydrogel scaffold can enhance tendon-to-bone healing and improve the ultimate load to failure in rabbits.
作者
黄成龙
赵松
程飚
陈刚
潘界恩
HUANG Chenglong;ZHAO Song;CHENG Biao;CHEN Gang;PAN Jieen(Department of Orthopedics,Clinical Medical School,the Affiliated Shanghai No.10 People’s Hospital,Nanjing Medical University,Shanghai,200072,P.R.China;Department of Sports Medicine,Shanghai Jiao Tong University Affiliated Sixth People’s Hospital,Shanghai,200233,P.R.China;Department of Orthopaedics,the Second Affiliated Hospital of Jiaxing University,Jiaxing Zhejiang,314000,P.R.China)
出处
《中国修复重建外科杂志》
CAS
CSCD
北大核心
2020年第9期1177-1183,共7页
Chinese Journal of Reparative and Reconstructive Surgery
基金
嘉兴市科技计划项目(2018AY32006)
浙江省自然科学基金资助项目(LBQ20H060001)。
关键词
肩袖损伤
微骨折
水凝胶
腱-骨愈合
兔
Rotator cuff tear
microfracture
hydrogel
tendon-to-bone healing
rabbit
作者简介
通信作者:程飚,Email:13681973702@sina.cn。
