新型生物降解材料输尿管支架的生物相容性研究

目的探讨新型生物降解材料输尿管支架己内酯丙交酯乙交酯三元共聚物（PCLGA20：60：20）的生物相容性。方法通过肌肉埋植实验，初步评价材料生物相容性；通过PCLGA支架输尿管植入实验，观察支架管在输尿管局部组织相容性情况。结果测试材料肌肉埋植引发的局部组织反应为非细菌性炎症反应，材料周围纤维包裹层厚度小于30μm；输尿管植入实验中，PCLGA支架在12周内完全降解，输尿管腔内无材料碎片残留，支架植入术后的输尿管炎症反应随材料降解而逐渐消退。结论PCLGA材料具有良好的生物相容性，是加工生物降解输尿管支架的理想材料。     

人工神经移植物丝素蛋白导管的生物相容性的初步研究

目的初步探讨人工神经移植物丝素蛋白导管的生物相容性。方法将丝素蛋白导管植入兔子皮下,术后4周、8周、12周、24周取材,切片,HE染色,观察局部组织反应。结果大体观察和组织切片观察,局部组织反应轻,纤维包裹逐渐变薄,丝素蛋白导管至24周完全降解。结论丝素蛋白导管有良好的生物相容性和可降解性,是理想的人工神经移植物。     

脱细胞牛心包构建引导骨再生膜的初步研究

目的制备具有良好生物相容性和适宜降解吸收时间的引导骨组织再生（guided bone regeneration，GBR）膜材料。方法采用0．25％Trypsin＋0．5％Triton X-100酶联脱细胞法对新鲜牛心包进行脱细胞处理，将脱细胞牛心包（A组）、甘油保存脱细胞牛心包（B组）、碳化二亚胺[1-ethyl-3-（3-dimethylamino propyl）carbodiimide hydrochloride，EDAC]交联脱细胞牛心包（C组）、甘油保存EDAC交联脱细胞牛心包（D组）4种膜材料分别植入38只SD大鼠背部皮下，不植人材料为E组。于2、4、8和16周分别处死大鼠7、12、12和7只，观察周围组织反应及材料的降解吸收情况。结果4种材料植入动物体内均有不同程度的炎性反应和纤维囊膜形成。术后4周，A组和C组的炎性反应轻微，纤维包膜变薄。A组膜材料吸收替代时间为8周左右，C组吸收替代时间为16周左右；16周时B组和D组材料仍有纤维包膜。结论EDAC交联脱细胞牛心包具有良好的生物相容性和理想的降解性能，在动物体内能顺利被自体组织替代。     

人工肋骨支架多孔磷酸钙的制备及体内降解研究

目的 对多孔磷酸钙(CPC)体内降解情况进行研究,为其作为组织工程化人工肋骨支架提供实验基础.方法 将CPC材料埋植于兔皮下,并于预定的时间点将材料取出,称重并送扫描电镜检查,以观察其降解情况;其周围组织则进行苏木素-伊红(HE)染色和透射电镜检查,以观察其炎症反应和生物相容性.结果 CPC材料在术后2、4、8、12、24周的生物吸收率分别为(2.500±0.098)%、(7.000±0.167)%、(10.000±0.242)%、(14.000±0.251)%、(30.000±0.177)%,降解速度平稳,能有效维持缺损部位的稳定性;HE染色和透射电镜结果 显示其炎症反应于4周时消失,有良好的生物相容性.结论 CPC的体内降解速度平稳,组织相容性好,是承重部位和非承重部位的良好组织工程支架.     

几丁质-胶原蛋白膜的制作及皮下埋植实验

目的 探讨几丁质—胶原蛋白膜作为真皮支架的可行性。方法 以酸溶法制备胶原溶液，添加一定比例的脱乙酰化几丁质，冻干成膜，0．05％戊二醛溶液浸泡交联，行体外酶降解实验，检测其耐受酶降解能力；将制备的几丁质—胶原蛋白膜包埋于36只SD大鼠皮下，术后3、5天，1、2、3、4、6、8和12周取材，捡a其组织相容性、血管化能力及材料在体内障解情况。结果 制备的几丁质—胶原蛋白膜，呈微黄、半透明状，纤维排列呈网状，一例较光滑，孔小，另一例孔稍大，孔径大小保持在50～250μm之间，其体外降解缓慢。皮下埋植实验术后5天～2周显示材料具有良好的组织相容性，无明显炎性反应，血管化早，体内障解缓慢；8周后经改建可形成纤维排列较规则的类真皮样结构。结论 几丁质—胶原蛋白膜具有较好的物理及生物学性能，组织相容性好，血管化能力强，体内、外降解缓慢，具有良好的真皮替代功能。     

新型可注射性磷酸钙骨水泥对松质骨成骨作用的实验研究

目的：研制一种新型的、可注射的磷酸钙骨水泥，并测试该骨水泥的成分、理化学特性及其在松质骨内的生物隆解和成骨特性，探讨该骨水泥在松质骨内的代谢情况。方法：根据相关文献合成一种含有β-磷酸三钙、磷酸二氢钙、碳酸钙和纳米相羟基磷灰石的磷酸钙骨水泥，并用含藻酸钠的液相成分将该骨水泥调制成为用注射器和16号穿刺针操作的注射物。在新西兰大白兔的股骨髁部钻取直径为2mm的骨洞。注入该骨水泥。在术后4、8、12、16周分别取标本，骨锐钙后石蜡包进并行HE染色，光镜下观察该骨水泥在松质骨内的降解及新骨再生情况。扫描电镜观察骨-骨水泥界面的超微结构。结果：采用Gillmore双针法测试该型骨水泥的初凝时间为25-30min，终凝时间为17-20h，扫描电镜发现该骨水泥的颗粒较小、孔隙率较高。术后切片见骨水泥在松质骨内相容性良好。4周时骨水泥在体内开始降解，12周为降解反应的高峰期，16周降解反应基本完成，降解同时有大量骨小梁生成。结论：该型磷酸钙骨水泥可操作性强、生物相容性好、具有骨传导和骨诱导作用，有望成为老年骨质疏松性椎体压缩骨折治疗中较好的填充剂。     

纳米磷酸钙/氧化锆骨组织工程支架体内降解的实验研究

目的研究纳米磷酸钙/氧化锆骨组织工程支架材料体内降解特性,为进一步构建组织工程化纳米人工骨提供研究依据。方法制作兔股部肌袋,将灭菌的纳米磷酸钙/氧化锆骨组织工程支架材料植入肌袋内,在植入4周、8周、12周、16周时取材通过大体、组织学、扫描电镜观察材料降解情况,同时将材料取出后煅烧,测量残余无机物含量,判断降解的量,同时进行X线衍射实验,测量残余材料的组成。结果材料植入8周内降解较慢,生物力学强度减低不明显,12周时降解加速,材料强度明显减低,16周时新骨形成明显,降解残余材料分布于新形成的骨组织内部,X线衍射发现12周时材料内有羟基磷灰石成分出现,提示有新骨形成,16周时羟基磷灰石成分明显增多。结论纳米磷酸钙/氧化锆骨组织工程支架材料具有较好的降解性和生物相容性,具有诱导成骨作用,可作为骨组织工程的支架材料。     

牡蛎壳材料填充兔股骨骨缺损的实验研究

目的评价牡蛎壳材料填充兔骨缺损的生物相容性、降解性及成骨能力。方法将牡蛎壳用机械方法碾碎致牡蛎壳粉末。建立牡蛎壳材料修复兔股骨下段骨缺损动物模型。应用组织学、影像学、大体观察研究该材料的生物相容性、降解能力及成骨能力。结果术后组织无明显排斥反应,8周牡蛎壳材料开始降解,16周材料基本降解,24周材料完全降解。结论牡蛎壳材料具有良好的生物相容性,在体内可以发生生物降解,能促进骨修复,成骨方式为传导成骨,呈内向性。     

生物衍生材料构建组织工程肌腱体内植入的实验研究

目的 探讨用同种异体肌腱细胞与生物衍生肌腱材料体外联合培养后植入体内，构建组织工程肌腱的可行性。方法 选用四川锦猴15只，手术造成纤维鞘管内屈指深肌腱2．5cm缺损后，分三组。A组：生物衍生肌腱材料构建的组织工程肌腱移植组；B组：单纯生物衍生肌腱材料移植组；C组：自体肌腱移植组。术后1、2、3、6和12周分期观察植入物的大体形态、组织学和超微结构，BrdU标记表达。结果 A组植入体内后肌腱细胞能继续增殖，细胞形态随着时间增加而逐渐趋于正常，形成的肌腱呈白色且有光泽、致密，组织学可见胶原纤维排列较为规则，12周肌腱细胞仍成活并分泌胶原，BrdU表达为阳性；B组植入体内3周后材料逐渐变细，12周后材料被逐渐降解吸收出现中断；C组植入体内2周后桥接部有纤维连接，排列较为规则，肌腱愈合。A组分别于3、6、12周进行扫描电镜观察可见肌腱细胞排列均匀，胶原纤维相互连接形成网状，主体趋势与肌腱走行方向一致；透射电镜下可见细胞核仁清晰，细胞器丰富。随时间的增加A、C组与B组的差异明显增大。结论 同种异体肌腱细胞与生物衍生肌腱材料复合构建的组织工程肌腱，植入免疫功能正常的动物体内能够再生出肌腱样组织，植入的肌腱细胞具有生命力，新生的肌腱组织在大体、组织学方面与正常肌腱相似。     

甲壳素短纤维对聚己内酯体内的降解作用

目的 对纯聚己内酯（PCL）和甲壳素短纤维增强PCL复合材料进行体内降解实验研究，观察其理化性能变化及组织反应情况，为临床应用提供有价值的实验依据。方法 将纯PCL和甲壳素短纤维增强PCL植入兔背部脊柱两侧肌肉内，于2、4、8、12、16、24周取材，分别测试两种材料的生物吸收率、弯曲强度和弯曲模量，并行组织学和透视电镜观察。结果 甲壳素短纤维增强PCL初始强度大于纯PCL，在体内植入过程中，生物吸收率大于纯PCL，力学性能先高后低，强度和模量值24周时与初始值相差不大。未见材料周围组织变性、坏死或肉芽肿异常增生现象。结论 PCL复合甲壳素纤维后，加快降解速度，提高力学性能，材料-组织界面炎性反应轻，是一种具有开发价值的新型胸壁缺损修补及骨科内固定材料。     

聚磷酸钙纤维作为肌腱组织工程支架材料的体外实验研究

目的　探讨编织的辫状聚磷酸钙纤维 (CPPF)支架 ,在体外物理性能及与肌腱细胞的吸附情况。　方法　 CPPF直径 1 5μm,编织成横截面积为 3mm× 2 mm的辫状支架 ;体外测试其拉伸强度、孔隙率及吸水率。将体外培养 SD大鼠原代趾屈肌腱细胞 ,以 5× 1 0 6/ ml浓度与 CPPF辫状支架或 型胶原涂层的 CPPF辫状支架进行体外混合培养 ,组织学观察材料与细胞的吸附情况。　结果　编织的 CPPF辫的平均拉伸强度为 (1 2 2 .80± 1 7.34) N;平均吸水率为61 .56%± 1 4 .57% ;平均孔隙率为 50 .2 9%± 8.1 6%。肌腱细胞与 CPPF支架纤维的吸附较差 ,与 型胶原涂层后的CPPF支架纤维吸附良好。　结论　CPPF有可能成为一种较理想的构建肌腱组织工程复合型支架的新型材料     

聚磷酸钙纤维/磷酸钙骨水泥复合材料修复骨缺损的实验研究

目的：探讨聚磷酸钙纤维（calcium polyphosphate fiber，CPPF）和磷酸钙骨水泥（calcium phosphate cement．CPC）复合材料修复骨缺损的能力及作为人工骨修复替代材料的可行性。方法：选用新西兰大白兔双侧桡骨制作骨缺损模型，将CPPF／CPC复合材料植入左侧骨缺损处，右侧骨缺损以自体微小颗粒骨植入作为实验对照，另做不植入任何物质的骨缺损作空白对照。在2、4、8、12周时分别进行大体观察、X线摄片、组织学切片观察，8、12周时进行扫描电镜观察及骨密度测定，12周时进行力学测试。结果：CPPF／CPC人工骨组与微小颗粒骨组骨缺损均完全修复，空白对照组骨缺损未见修复，CPPF／CPC与微小颗粒骨两组间X线评分、骨密度及力学测试指标比较，差异均无统计学意义（P〉0．05）。结论：CPPF／CPC复合材料具有良好的骨传导能力、力学特性及生物相容性，有望成为骨组织工程中修复骨缺损的理想材料。     

组织工程肌腱低温贮存的初步研究

目的　研究深低温冻存组织工程肌腱适宜的抗冻剂。方法　选用近交系裸小鼠 6 4只 ,4只为空白对照组 ,6 0只左侧为实验组 ,右侧为对照组。将第 5 4代转化人胚肌腱细胞与碳纤维和聚羟基乙酸编织带体外复合培养构建组织工程肌腱。组织工程肌腱制备完成后在 1、2、3和 4号抗冻剂保护下液氮冻存 2个月。快速复温后植入实验组修复跟腱缺损 ,缺损长度为 5 mm,占裸鼠跟腱总长 6 5 .7% ;对照组组织工程肌腱不经冻存处理。术后 2、4、6、8和 12周后各组取出 ,观察形态学、组织学和免疫组织化学变化 ,并行短串联重复位点检测。结果　实验组体内植入的肌腱细胞形态随时间增加而逐渐恢复正常 ,合成胶原能力逐渐增强 ,12周后仍有肌腱细胞存活并具有分泌 I型胶原功能 ,与对照组差异逐渐减小。经 1号抗冻剂保存的肌腱细胞线粒体空泡减少 ,肌腱细胞排列整齐 ,胶原纤维增粗并连接。结论　 1号抗冻剂可以在深低温下保护组织工程肌腱     

颗粒骨的制备及修复骨缺损的研究

目的 观察聚磷酸钙纤维(CPPF)磷酸钙骨水泥(CPC)、微小颗粒骨复合物体外降解特性及体内修复骨缺损的能力.方法 将CPPF、CPC、微小颗粒骨按质量比1∶4∶4制成复合人工骨,通过PH值、重量、抗压强度的变化,观察人工骨在pH7.4的37℃磷酸盐缓冲液(PBS)中的降解性能.通过大体、X光片、组织学观察及力学测试来检测复合人工骨的体内修复骨缺损的能力.结果 体外实验证实:CPPF/CPC/颗粒骨复合材料孔隙率为72.1%,CPC/颗粒骨孔隙率为58.2%;扫描电镜显示CPPF/CPC/颗粒骨复合材料的孔径为100～400 μm,CPC/颗粒骨为50～300 μm;两组样品溶液pH值在12周内基本维持恒定;CPPF/CPC/颗粒骨复合材料0～4周重量变化较小,4～8周下降较快,12周为初始重量50%,CPC/颗粒骨复合材料在0～6周变化较小,6周后重量下降较快,12周时为初始重量70%;CPPF/CPC/颗粒骨复合材料初始抗压强度9.28 MPa,CPC/颗粒骨复合材料初始抗压强度6.21 Mpa,两者有统计学意义.CPPF/CPC/颗粒骨强度在0～4周下降较慢,4周后下降较快,12周时为0.1,8 MPa,CPC/颗粒骨强度均匀下降,12周时为0.24 MPa.体内实验:CPPF/CPC/颗粒骨复合材料修复骨缺损效果优于其他各组,且差异有统计学意义(P＜0.05).结论 复合材料以其优良的生物学性能有望成为理想的骨替代材料.     

Ultrasound sonography in the diagnosis and follow-up of Achilles tendon rupture

In addition to allowing definite diagnosis of Achilles tendon rupture and localization of the rupture site, ultrasonography also enables the examiner to grade the rupture and the course of healing for quantity and quality. Twenty patients with subcutaneous achilles tendon rupture were examined in a prospective study that is still in progress. In this trial an operative and a conservative-functional treatment with a newly developed shoe were compared. The dynamic examination revealed adaptation of the tendon in plantar flexion in two-thirds of the patients. After 2 weeks continuity of the tendon was restored in all patients. A remarkable increase in the regeneration of the tendon at the rupture or suture site was observed from the 4th to the 12th week. The variations in tendon structure were assessed, and a classification is presented.     

Extracellular matrix scaffolds are repopulated by bone marrow-derived cells in a mouse model of achilles tendon reconstruction.

The extracellular matrix derived from porcine small intestinal submucosa (SIS-ECM), an FDA-approved material currently used clinically for rotator cuff repair, has been shown to attract bone marrow-derived cells during in vivo remodeling of a subcutaneous implant and produce chemoattractant peptides following chemical degradation in vitro. The purpose of the present study was to determine if bone marrow-derived cells participate in the long-term remodeling of the Achilles tendon in a mouse model when repaired with SIS-ECM. A 2-mm gap was produced in the Achilles tendon of 40 chimeric mice produced to express green fluorescent protein (GFP) in all of their bone marrow-derived cells. Tendons were repaired by replacing the resected section with autologous tendon tissue or with a single layer sheet of lyophilized SIS-ECM. Four animals from each treatment group were sacrificed at 1, 2, 4, 8, and 16 weeks, and sections were harvested for histologic and fluorescence microscopy. Both groups showed accumulation of GFP-expressing marrow-derived cells at the site of tendon remodeling at 1 and 2 weeks that were associated with areas of angiogenesis and inflammation. By 16 weeks, the SIS-ECM-treated group showed GFP expressing cells throughout the remodeled tendon in the absence of any inflammatory response, while the autologous tendon repair group showed no GFP expressing cells within the tendon except for occasional cells in the lumen of blood vessels. An SIS-ECM scaffold used for tendon repair recruits a population of bone marrow-derived cells that participates in the long-term remodeling process. The ability of SIS-ECM to recruit a population of marrow-derived cells to the remodeling site may alter the default mechanism of tendon healing. The involvement of these cells in the remodeling process may explain in part the process of site specific constructive remodeling as opposed to scar tissue formation when the ECM is used as a biologic scaffold for tendon reconstruction.     

Management of chronic ruptures of the Achilles tendon

Chronic ruptures of Achilles tendons are those that present four to six weeks after the original injury. They have become more common as acute Achilles tendon injuries have become more frequent, and they are associated with considerable functional morbidity. Most surgeons agree that chronic ruptures should be managed operatively. Diagnosis is based predominantly on history and clinical examination. Real-time, high-resolution ultrasound and magnetic resonance imaging are helpful in preoperative planning or as a diagnostic aid. Local tissue, local tendons, and allografts can be used to reconstruct the tendon, and end-to-end repair is possible if the gap is <2.5 cm. Compared with acute injuries, chronic injuries are associated with a higher rate of postoperative infection and more prolonged recovery.     

Achilles Tendon Repair with Acellular Tissue Graft Augmentation in Neglected Ruptures

Neglected Achilles tendon rupture injuries present surgical challenges because of the quality and quantity of tendon tissue during repair combined with the magnitude of mechanical forces placed on this tendon. The purpose of this study was to evaluate the effects of an acellular human dermal tissue matrix, GRAFTJACKET, as an augmentation material in neglected Achilles tendon repair. Nine patients with neglected Achilles tendon ruptures were evaluated and followed up for a minimum of 20 months. Primary repair was followed by augmentation with the graft and suturing circumferentially around the tendon. Patients were placed in an early, functional rehabilitation program with postoperative evaluation at 3, 6, and 12 months. Outcome scores were calculated based on the American Orthopaedic Foot and Ankle Society ankle-hindfoot scoring system. At 20 to 30 months postoperative follow-up range, there has been no incidence of re-rupture or recurrent pain. The average return-to-activity time was 15.2 +/- 1.7 weeks. The results from this retrospective clinical series suggest that using an acellular human dermal tissue matrix to augment neglected Achilles tendon rupture primary repair offers desirable return-to-activity time points and viable surgical alternative over previously reported surgical options.     

跟腱损伤修复术后局部软组织缺损的处理

目的探讨跟腱损伤修复后局部软组织坏死致跟腱外露的处理方法。方法1996年4月-2006年4月,共收治24例跟腱修复术后因局部软组织坏死致跟腱外露的患者。其中男17例,女7例;年龄16-59岁。损伤原因开放性损伤8例,其中机器绞伤2例,重物砸伤3例,车轮绞伤3例;闭合性损伤16例,均为运动损伤。单纯行皮神经营养血管修复软组织缺损11例,其中腓肠神经营养血管皮瓣移位修复8例,隐神经营养血管皮瓣移位修复3例;跟腱修复加上述皮神经营养血管皮瓣移位修复软组织缺损13例。伤后至本次手术时间为9-76d,跟腱外露至本次手术修复的时间为3-65d。结果术后所有移位皮瓣均成活良好,质地好,外露跟腱被覆盖。其中4例皮瓣边缘少许黄色分泌物经2-3周换药后痊愈,6例行二期皮瓣修薄术。18例获6-24个月随访,皮瓣无破溃,不影响穿鞋,两点辨别觉为12-20mm。踝关节功能按AOFAS（美国足踝外科协会）标准评分,优8例,良6例,可3例,差1例,优良率为77.8%。13例提踵功能良好,3例能完成提踵功能,力量较健侧差,2例不能提踵。结论跟腱损伤修复术,若处理不当,易导致局部软组织坏死,跟腱外露。应尽早视情况行单纯皮神经营养血管皮瓣移位修复,或跟腱修复加皮神经营养血管皮瓣移位术。软组织修复及跟腱修复应力争同期进行。     

Granuloma formation secondary to Achilles tendon repair with nonabsorbable suture

INTRODUCTION

Several complications can be observed after Achilles tendon repairs. In this study we aimed to report granuloma formation secondary to Achilles tendon repair with Ethibond (Ethicon INC, Somerville, New Jersey) suture.

PRESENTATION OF CASE

A 31 year-old man operated for Achilles tendon rupture. The Ethibond suture was used for primary repair. The patient attended to polyclinic with the complaints of swelling and discharge around the operation site four months after operation. A mass around distal portion of the Achilles tendon was detected. The granulomatous tissue was excised. Inside the mass Ethibond suture was detected. On histopathologic examination, typical findings of the foreign body reaction were observed. No microorganism was cultivated in the tissue culture. The patient has no complaint on the twelfth month control after surgery.

DISCUSSION

The results of primary repair of Achilles tendon are good but several complications were reported. In tendon repairs generally nonabsorbable sutures are used. The Ethibond is nonabsorbable, braided suture. In the literature, granuloma formations secondary to the suture materials such as polygylactine and braided polyethylen–polyester after Achilles tendon repair were reported but granuloma secondary to the Ethibond is very rare.

CONCLUSION

Although Ethibond suture is a strong and safe material for Achilles tendon repairs it may cause soft tissue problems such as granuloma.