蚕丝组织工程肌腱修复肌腱缺损的实验性研究

[目的]探讨用蚕丝与同种异体肌腱细胞联合培养植入体内,构建组织工程化肌腱的可行性。[方法]以罗曼鸡为实验对象分两组,术后第2、4、6、8周进行病理学检查、生物力学和拉伸度的测定。数据采用SPSS 13.0进行统计分析。[结果]细胞组在胶原的合成以及力学检测均明显优于非细胞组(P0.05)。[结论]本实验的结果说明蚕丝材料对肌腱细胞的吸附明显,降解缓慢,抗拉性能优越,构成组织工程化肌腱,可能会在肌腱缺损的治疗方面发挥出巨大潜能。     

骨髓间充质干细胞促进骨-肌腱结合部位早期愈合的动物生物力学实验研究

[目的]通过生物力学研究,观察骨髓间充质干细胞对骨-肌腱结合部愈合的影响.[方法]采用骨髓穿刺、全骨髓培养法获取兔骨髓间充质干细胞.24只18周龄新西兰大白兔随机分为2组,实验组将骨髓间充质干细胞与Pluronic F-127载体材料结合后,植入兔髌骨部分切除模型,对照组只进行手术,不植入细胞.在术后6、12、18周处死动物取标本(n=4)进行生物力学检测评估骨-肌腱结合部位的愈合恢复情况.[结果]生物力学结果显示相同时间点实验组拉断负荷及极限拉应力均大于对照组,差异有统计学意义(P<0.05),提示实验组恢复较对照组迅速.[结论]相同时间点实验组拉断负荷、极限拉应力均大于对照组.实验组的力学特性明显高于对照组.骨髓间充质干细胞可以促进骨-肌腱结合部细胞早期愈合,提高其力学特性.     

骨膜促进骨-肌腱结点愈合的研究

[目的]探讨骨膜对骨-肌腱结合部位愈合的影响,通过实验证明骨膜促进骨-肌腱结合部位细胞增生,进而促进该部位愈合.[方法]48只18周龄新西兰大白兔随机分为2组,实验组将骨膜游离并植入兔髌骨部分切除模型中骨-肌腱结点中,对照组只进行手术,不植入骨膜.在术后4、8、12周处死动物取标本进行大体和组织学观察.[结果]大体观察可见实验组骨-肌腱结合部位愈合较早.组织学检查显示实验组术后4、8周骨-肌腱结合部组织愈合明显,以从松质骨再生和骨-肌腱愈合接点纤维软骨带的再生为特征,较对照组迅速,提示早期实验组恢复较对照组迅速.[结论]骨膜可以促进骨-肌腱结合部位细胞增生,增加细胞基质合成,促进新生骨和纤维软骨移行带形成,促进其愈合.     

几种制备因素对同种骨移植物的生物力学特性的影响

本文研究了超声清洗,冷冻干燥和Co~(60)r射线辐照灭菌几项制备因素对同种骨移植物的生物力学特性的影响。结果表明,实验组和对照组之间无显著性差异,即这些制备因素对同种骨移植物的生物力学特性无影响。     

深低温冷冻异体肌腱移植的组织学和生物力学研究

[目的]探讨深低温冷冻同种异体肌腱替代自体肌腱进行移植治疗肌腱缺损的可行性及移植后异体肌腱的形态学和生物力学性能的动态变化.[方法]采用兔跟腱缺损修复模型,经深低温冷冻的同种异体跟腱为实验组.自体跟腱移植为对照组,分别在术前及术后2、4、8周时对实验组同种异体跟腱及对照组自体跟腱进行大体观察、组织学检查和生物力学测试.[结果]同种异体跟腱与自体跟腱在移植前和移植后2、4、8周时其大体观察、组织学检查和生物力学测试等各项指标均无明显差异,显示同种异体跟腱和自体跟腱有相类似的结构及愈合过程.另外,同种异体跟腱在移植后其力学性能(除衰竭应变外)均比移植前明显降低.随时间推进有上升的趋势,但8周时仍明显低于移植前水平.[结论]深低温冷冻同种异体肌腱可替代自体肌腱应用于移植修复肌腱缺损.同时,由于移植后肌腱力学性能明显下降,需给予适当保护,防止过度牵拉而导致衰竭.     

辐照对rhBMP-2骨诱导活性的影响

目的探讨不同剂量γ射线辐照对基因重组人骨形态发生蛋白2(rhBM P-2)骨诱导活性的影响及胶原载体的作用。方法以胶原海绵为载体制成rhBM P-2胶原复合物,分为4类:(Ⅰ)对照组:复合物未辐照;(Ⅱ)复合物辐照组:剂量为15、20、25和50kGy;(Ⅲ)载体辐照组:胶原载体接受50kGy辐照,然后复合未辐照的rhBM P-2;(Ⅳ)BM P辐照组:将rhBM P-2辐照25和50kGy,然后复合于胶原载体。各类BM P胶原复合物植入大鼠股骨肌袋内,术后2周和4周取出包块,进行大体、X线和组织学观察,通过组织形态分析对成骨进行定量分析。结果术后2周,复合物辐照15、20和25kGy组与对照组包块的大体、X线和组织学所见相似,包块内见大量未成熟的编织骨,成骨定量分析见20kGy组与对照组差异无统计学意义;复合物辐照25kGy组新生骨量明显低于复合物辐照15kGy组(P<0.05);复合物辐照50kGy和BM P辐照组无新骨形成。术后4周,各组均出现含有骨髓的成熟骨组织,其中复合物辐照25kGy组与对照组相似;复合物辐照50kGy组有成熟骨但数量较少;载体辐照和BM P辐照组新生骨量明显少于对照组。结论20和25kGy剂量辐照对rhBM P-2骨诱导活性没有影响或仅有一过性抑制;在辐照过程中,胶原载体对BM P具有保护作用。     

大鼠和家兔辐照灭菌去抗原—自溶同种骨移植片骨移植研究

利用大鼠颅骨钻孔移植和家兔尺骨缺损移植实验观察经不同方法制备的去抗原-自溶同种骨移植片(AAA)骨的愈合效果,并与自体骨、新鲜同种骨、不脱灰AAA骨及异种骨相比较,结果发现脱灰AAA骨具有较好的骨诱导活性;25kGy剂量的辐照可以明显降低移植大鼠颅骨的愈合效果,但对家兔影响甚小。辐照AAA骨的愈合效果明显优于新鲜同种骨。     

人同种异体肌腱的实验研究及临床应用

[目的]在无水甘油保存液中保存人同种异体肌腱,并做人肌腱移植,评估人同种异体肌腱保存的可行性.[方法]将人同种异体肌腱随机分为2组,即生理盐水组、无水甘油组,各组在12个月进行细菌学检查;将人同种异体肌腱随机分为2组,即新鲜肌腱对照组、无水甘油组肌腱,保存12个月后行生物力学测定;无水甘油组肌腱保存12个月后复水修复人的肌腱缺损.[结果]12个月内无水甘油保存液无细菌生长,保存12个月后进行肌腱的生物力学测试.无水甘油肌腱组:最大拉伸力均值367.2 N,标准差141.6;拉伸刚度107.1 N/mm,标准差31.9.新鲜肌腱组:最大拉伸力均值418.0 N,标准差114.6;拉伸刚度86.0 N/mm,标准差24.6;无水甘油组肌腱修复肌腱缺损22例,28条肌腱,随访7个月～7.8年,平均5.8年,TAM法进行功能测定:优良率72.7％,可13.6％,差13.6％.[结论]无水甘油保存液具有抑制细菌作用,无细菌生长;在无水甘油保存液中常温对肌腱进行保存,在12个月内,无水甘油组肌腱和新鲜肌腱在生物力学上无统计学差异;在无水甘油保存液保存的肌腱可以替代自体肌腱用于肌腱移植,并取得了比较满意的临床效果.     

前交叉韧带重建同种异体移植物灭菌及保存方法的研究进展

目的综述用于前交叉韧带(anterior cruciate ligament,ACL)重建的同种异体移植物的灭菌和保存方法研究现状及进展。方法广泛查阅有关同种异体移植物灭菌和保存方法的文献,并进行分析总结。结果同种异体移植物灭菌方法较多,最常用的是γ射线辐照,但最佳辐照剂量仍不清楚。电子束辐照也是可选择方法之一,但辐照剂量过大对移植物塑形有明显影响。物理与化学结合的联合灭菌法仍处于探索阶段。深低温冷冻保存是目前最常用的一种保存方法,注意坚持"缓慢降温,快速复温"原则,以减少冰晶对移植物的影响。结论同种异体移植物灭菌及保存方法会影响ACL重建术后效果,因此临床医生在选择同种异体移植物时应综合考虑其灭菌和保存方法。     

雷公藤甲素对同种异体肌腱移植修复鸡肌腱缺损的作用

目的雷公藤甲素具有抗排斥作用,探讨其在同种异体肌腱移植修复鸡肌腱缺损中的作用。方法 4月龄健康清洁级雄性来亨鸡64只,体重1.9～2.3 kg,取右足第3足趾肌腱制备肌腱缺损模型并行同种异体肌腱修复。根据是否给予雷公藤甲素,随机分为两组(n=32)。实验组术后给予雷公藤甲素100μg/(kg.d),共3周;对照组正常喂养。术后观察动物一般情况,于1、2、3、4周各组取4只动物大体观察移植肌腱情况,其中1、3周取材行组织学观察、2、4周行透射电镜观察。术后3、6周各组另取8只动物采血行流式细胞学检测,取肌腱行生物力学检测。结果术后实验动物均存活至实验完成。标本大体观察显示,随时间延长,两组肌腱周围充血、水肿缓解,实验组见疏松粘连带,对照组为广泛致密纤维组织粘连带。组织学观察示,术后1、3周实验组炎性反应均较对照组轻。透射电镜观察示,术后2、4周,实验组成纤维细胞核大,常染色质丰富,异染色质较少;对照组成纤维细胞细胞质内有少量粗面内质网,腔小,内容物少。术后3、6周,实验组CD4+、CD8+T淋巴细胞均较对照组少,CD4+/CD8+T淋巴细胞比值低于对照组;实验组肌腱最大拉伸断裂强度大于对照组,拉断粘连带功耗小于对照组;以上指标比较差异均有统计学意义(P<0.05)。结论雷公藤甲素可以降低鸡同种异体肌腱移植中的免疫排斥反应,增强肌腱愈合强度,减轻肌腱粘连程度。     

Effects of Chemical Sterilization and Gamma Irradiation on the Biochemical and Biomechanical Properties of Human Tendon Allografts In Vitro Study

ObjectivePre‐implantation sterilization procedures for tendons are important measures to reduce the risk of disease transmission, however these procedures may compromise tendon microarchitecture and biomechanical properties to varying degrees. We explore the effects of different sterilization procedures on the micro‐histology, biomechanical strength and biochemical properties of human tendon allografts in vitro study.MethodsThe tendon allografts were harvested from cadaveric donors after the donors were serologically screened by antibody or nucleic acid testing of infectious agents. All samples were divided into five groups, which were fresh‐frozen group (control group), 15 kGy gamma irradiation group, 25 kGy gamma irradiation group, 70% ethanol group, and peracetic acid‐ethanol group. Each group included 10 tendons for testing. Histological staining and transmission electron microscopy were applied to observe the internal structure and arrangement of tendon collagen fibers, while the machine learning classifier was trained to distinguish the darker cross‐sections of collagen fibers and brighter backgrounds of the electron micrograph to detect the distribution of diameters of tendon collagen fibers. The viscoelasticity, mechanical properties and material properties of tendon allografts were examined to detect the influence of different intervention factors on the biomechanical properties of tendons.ResultsHistological staining and transmission electron microscopy showed that the structure of fresh‐frozen tendons was similar to the structures of other experimental groups, and no obvious fiber disorder or delamination was observed. In the uniaxial cyclic test, the cyclic creep of 25 kGy irradiation group (1.5%) and peracetic acid‐ethanol group (1.5%) were significantly lower than that of the control group (3.6%, F = 1.52, P = 0.039) while in the load‐to‐failure test, the maximum elongation and maximum strain of the peracetic acid‐ethanol group were significantly higher than those of the control group (F = 4.60, P = 0.010), and there was no significant difference in other biomechanical indicators. According to the experimental results of denatured collagen, it could be seen that no matter which disinfection procedure was used, the denaturation of the tendon sample would be promoted (F = 1.97, P = 0.186), and high‐dose irradiation seemed to cause more damage to collagen fibers than the other two disinfection procedures (296.2 vs 171.1 vs 212.9 μg/g).ConclusionBiomechanical experiments and collagen denaturation tests showed that 15 kGy gamma irradiation and 70% ethanol can preserve the biomechanical strength and biochemical properties of tendons to the greatest extent, and these two sterilization methods are worthy of further promotion.     

Mechano-receptors in the flexor tendons of the hand

Flexor tendons of the hand obtained fresh at autopsy were studied histologically for free nerves and mechano-receptors. In addition to free nerves, Ruffini endings, Pacinian corpuscles and Golgi tendon organs were found throughout the tendons. Golgi tendon organs and Pacinian corpuscles were subjectively in greater numbers than Ruffini endings. The predominance of these two mechano-receptors indicates that position sense and kinetic activities of the fingers are well-served, as evidenced in hand movements.     

Biomechanical evaluation of flexor tendon function after hamate hook excision

PURPOSE: Hamate hook fractures are uncommon injuries for which treatment is controversial. Excision of the hamate hook is considered to be the preferred method of treatment but the effects of hamate excision are not clearly delineated. The purpose of this study was to determine what effect, if any, excision of the hamate has on flexor tendon function. METHOD: The biomechanical effects of hamate hook excision on flexor tendon function were studied in fresh cadaveric forearm specimens with wrists fixed in 3 positions (neutral, 30 degrees extension, 30 degrees extension with 30 degrees ulnar deviation). Flexor tendon force, flexor tendon excursion, and flexor tendon shift were evaluated. RESULTS: Flexor tendon force decreased after hamate hook excision (11% in neutral, 14% in 30 degrees extension, and 15% in 30 degrees extension with 30 degrees ulnar deviation). The flexor profundus tendons had a 7- to 11-mm increase in proximal tendon excursion after hamate hook excision depending on the position of the wrist, and the flexor profundus tendons of the small finger shifted 4 to 5 mm in ulnar direction. CONCLUSIONS: The hamate hook provides some biomechanical advantage for flexor tendon function and cadaveric changes in tendon force after its excision suggest that power grip may be decreased after hamate hook excision.     

自体组织工程化肌腱预制的初步研究

目的：应用组织工程技术研究组织工程化肌腱体内形成的可行性。方法：取成年家鸡的趾深屈肌腱，用酶消化法分离，培养肌腱细胞，将在体外扩增到一定浓度的肌腱细胞接种到聚羟基乙酸（PGA）上，形成细胞－材料复合物，体外培养5d后，将此复合物回植至自体右翼皮下，左侧以单纯PGA作为对照，培养后第3，4，6，8周取材，从大体，组织学等方面进行分析。结果；术后8周见组织工程化肌腱呈白色，有光泽，组织学见胶原组织平行排列，但仍可见未降解的PGA及少量炎性细胞，对照组则无任何组织形成，结论：自体肌腱细胞与生物材料复合后在免疫功能正常的自体动物体内能够再生出肌腱样组织，新生的肌腱样组织在大体，组织学等方面均与正常肌腱相似。     

腱缝合后鞘内置入法在Ⅱ区屈肌腱修复中的临床应用

目的介绍用腱缝合后鞘内置入法，治疗Ⅱ区屈肌腱损伤的方法和疗效。方法按该法治疗屈肌腱损伤４６例７７指。伸直型１２例２６指：经原腱鞘伤口缝合肌腱，术毕将肌腱缝合部置于近侧健康鞘管内。屈曲型３４例５１指：在肌腱远断端以远约０．５ｃｍ处另作腱鞘切口，经此切口将损伤腱近端拉出进行缝合，术毕将腱缝合口置于远端切口和原伤口间的完整鞘管内。结果术后随访到３８例５９指，随访时间为２个月～３年，平均１年８个月。按ＴＡＭ评定法评定疗效，优级：３０指，良级：１７指，余为中差级；总优良率达到７９．７％。锐器切割伤４３指，疗效优良者４２指占９７．７％；合并腱鞘及周围组织损伤１６指，疗效优良者５指占３１．３％。结论该术式对单纯指屈肌腱损伤疗效满意，这可能和术时腱鞘损伤轻，肌腱缝合口被健康鞘管包绕后，有利于肌腱的内源性愈合并减少了外源性愈合的参与有关     

手指腱鞘内屈肌腹损伤的急诊显微外科修复

目的 回顾性研究手指腱鞘内屈肌腱损伤急诊显微外科修复的效果.方法应用显微外科技术急诊修复手指腱鞘内屈肌腱损伤151例382条肌腱.结果优98例、良37例、可9例、差7例,优良率89.4%.结论手指腱鞘内屈肌腱损伤采用显微肌腱缝合方法并修复腱鞘,一期修复可获得较好疗效.     

电子束辐照预防肌腱粘连的实验研究

目的 探索放射辐照对预防肌腱粘连的影响.方法 30只鸡按时间2、4、8周随机分成3组,每组10只,设左足为实验组,右足为对照组.切断鸡双足第2、3、4趾趾深屈肌腱,用8字法缝合肌腱,术后不做外固定.左足于术后24 h内采用电子束照射(总剂量15 Gy),右足不作特殊处理.于术后2、4、8周分别做大体观察、生物力学测试、病理组织学观察.结果 发现在大体粘连性状、关节屈曲角度、肌腱滑动距离、病理组织学上,辐照实验足和未照射对照足差异有统计学意义(P＜0.01);肌腱最大抗断裂负荷上两足差异无统计学意义(P＞0.05).结论 肌腱术后放射辐照能明显抑制胶原过分增生,对预防肌腱损伤术后粘连有效,为临床应用提供实验模型.     

Improved Tendon Radioprotection by Combined Cross-linking and Free Radical Scavenging

Allograft safety is a great concern owing to the risk of disease transmission from nonsterile tissues. Radiation sterilization is not used routinely because of deleterious effects on the mechanical integrity and stability of allograft collagen. We previously reported several individual cross-linking or free radical scavenging treatments provided some radioprotective effects for tendons. We therefore asked whether a combination of treatments would provide an improved protective effect after radiation exposure regarding mechanical properties and enzyme resistance. To address this question we treated 90 rabbit Achilles tendons with a combination of cross-linking (1-ethyl-3-[3-dimethyl aminopropyl] carbodiimide [EDC]) and one of three scavenging regimens (mannitol, ascorbate, or riboflavin). Tendons then were exposed to one of three radiation conditions (gamma or electron beam irradiation at 50 kGy or unsterilized). Combination-treated tendons (10 per group) had increases in mechanical properties and higher resistance to collagenase digestion compared with EDC-only and untreated tendons. Irradiated tendons treated with EDC-mannitol, -ascorbate, and -riboflavin combinations had comparable strength to native tendon and had averages of 26%, 39%, and 37% greater, respectively, than those treated with EDC-only. Optimization of a cross-linking protocol and free radical scavenging cocktail is ongoing with the goal of ensuring sterile allografts through irradiation while maintaining their structure and mechanical properties.     

不同浓度透明质酸钠防肌腱粘连的对比研究

６０只白兔随机分为５组，于右后肢２、３趾屈肌腱Ⅱ区造成肌腱损伤，Ａ组伤腱不作处理，Ｂ、Ｃ、Ｄ、Ｅ组分别涂以０．５％、１．０％、１．５％、２．０％的透明质酸钠０．２ｍｌ，术后不同时间段取材，行大体，光镜观察、屈趾功能测定和计算机图像分析。结果：Ａ、Ｂ组腱周形成致密粘连，Ｃ、Ｄ组粘连较轻，Ｅ组几无粘连；透明质酸钠浓度与腱周组织中成纤维细胞计数、肌腱发生粘连长度的百分率间呈显著负相关（Ｐ＜０．０１），与屈趾功能呈显著正相关（Ｐ＜０．０１），提示用于防肌腱粘连的透明质酸钠浓度不宜低于１．０％，且浓度越高，效果越好。     

Flexor tendon repair in vitro: a comparative histologic study of the rabbit, chicken, dog, and monkey

Flexor tendon healing in four different animal species was explored in a tissue culture system. Ninety percent transverse lacerations were made in 88 tendon segments obtained from rabbits, chickens, dogs, and monkeys. The tendons were removed from culture and studied by light and electron microscopy at intervals of 3, 6, 9, and 12 weeks. A characteristic sequence of repair including epitenon thickening, cellular differentiation, cell migration, and phagocytosis was seen in each of the repaired tendons. The endotenon cells of several animal tendons appeared to be synthesizing collagen. There was a consistent difference in the rate of healing between the four species. The rabbit tendons demonstrated nearly complete closure of the repair site by 12 weeks. A lesser response was seen in the chicken, followed by the dog and monkey. The differences in healing rate appeared to be due to the non-species-specific in vitro culture media. The in vitro flexor tendon culture system is particularly useful in studying the tendon repair responses of various species with the contributions of vascularity and synovial cells excluded.