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61.
Abstract Background: In recent years, biomaterials are being found and frequently utilized in bone defects. They have also gained significant precedence in hand surgery. Objectives: The respective requirements for such replacement material will be cited and acknowledged in this article. The individual material groups will also be referred to in this review. An introduction to some of the customary bone replacement materials will be cited and concluded with a corresponding recommendation. Conclusion: The implantation of autologous cancellous bone is still regarded today as the “gold standard”. Nevertheless, the usage of bone replacement material can be an enormous advantage in certain indications. The original article can be found online at There was an error in the author’s affiliation and the address for correspondence was incomplete. Please note the correct institution and complete address: Department of Orthopedics and Traumatology, Hand-, Foot- and Reconstructive Surgery, Kreiskrankenhaus Gummersbach GmbH, Germany. Alexander von Friesen, MD Department of Orthopedics and Traumatology, Hand-, Foot- and Reconstructive Surgery Kreiskrankenhaus Gummersbach GmbH Wilhelm-Breckow-Allee 20 51643 Gummersbach Germany Phone (+49/2261) 171-575, Fax -449 e-mail: Friesen@kkh-gummersbach.de  相似文献   
62.
Autogenous cancellous bone and freeze-dried allogeneic cancellous bone were tested in a total of 41 adult male mongrel dogs. In each humerus, an implant with a commercially pure titanium fiber metal porous coating was placed in an overreamed cavity so that a uniform 3-mm gap was present between the implant and host cancellous bone. Graft material was placed in the gap of one humerus while the gap of the other humerus was left empty and served as a paired negative control. Histologically, both autograft and allograft appeared to aid repair of the defect, but quantitatively only autograft enhanced new bone formation within the defect. Treatment with autograft significantly increased the amount of bone ingrowth within the implants by nearly three-fold at 4 weeks and eight-fold at 8 weeks. The enhancing effect was recognizable as early as 2 weeks. The strength of fixation was increased by nearly seven-fold at 4 weeks and two-fold at 8 weeks in the autograft group, but this was only statistically significant at 4 weeks. Treatment with allograft did not enhance bone ingrowth at any time period, but had a small positive effect on strength of fixation at 4 weeks.  相似文献   
63.
Donor bone grafts are an important aspect of orthopaedic surgery. The use of plain film as a pathological screening tool before donor bone dispatch has revealed “lytic” lesions in proximal humeri. Donor demographics did not support the diagnosis of myeloma and subsequent computed tomography (CT) scans of these bones identified the lesions as air, not pathology. In total, 27 long bones were scanned and 100% (27/27 cases) exhibited air within the trabecular bone. Three distinct patterns were found: ovoid, linear/branching, and broad channel. A longitudinal course of CT scans was performed to identify at which stage air appeared within the bone. Pre-retrieval, preprocessing, and postprocessing scans revealed that air originated between the retrieval and preprocessing stages of donor bone preparation. There may be multiple aetiology of this phenomenon, including bone retrieval and natural decomposition.  相似文献   
64.
65.
目的 探讨一种良好的治疗腕舟骨骨折不愈合的方法 ,丰富治疗腕舟骨骨折不愈合的手术方式。方法 切除腕舟骨骨折不愈合之硬化骨 ,以克氏针贯穿固定骨折端 ,用带骨间掌侧动脉背侧支血管蒂桡骨瓣翻转移植治疗腕舟骨骨折不愈合 15例。结果 术后随访 3~ 6个月 ,骨折完全愈合 ;9~ 18个月 ,腕关节活动正常无痛。结论 前臂间掌侧动脉背侧支解剖位置恒定 ,变异少 ,位置较表浅 ,血管蒂长、口径粗、游离安全容易 ,血供充分 ,能有效地促进舟骨骨折愈合。  相似文献   
66.
韩培  蒋垚  陈旸  邵俊杰  张先龙 《上海医学》2004,27(5):327-330,i003
目的 研究重组骨形态发生蛋白-2(rhBMP-2)结合软骨下骨钻孔治疗犬关节软骨全层缺损的可行性,为临床应用提供实验依据。方法 依照软骨缺损处理方法的不同将64侧股骨髁随机均分为4组:①结合组:软骨下骨钻孔 胶原海绵吸附rhBMP-2充填软骨缺损;②BMP组:胶原海绵吸附rhBMP-2充填软骨缺损;③钻孔组:单纯软骨下骨钻孔;④对照组:不作处理或单纯用胶原海绵填塞。术后2、4、8、12周取材观察其大体、光镜、透射电镜、免疫组织化学情况。结果 除对照组仅有纤维组织修复外,其余3组均有不同程度的软骨修复,但结合组的修复在组织细胞形态、超微结构、Ⅱ型胶原含量等方面均明显优于其他两组。结论rhBMP-2结合软骨下骨钻孔能有效修复犬膝关节软骨的全层缺损,该技术可行,有望在临床应用。  相似文献   
67.
We describe a firm, effective suture-tying method using a tensioner for reattaching tibial avulsion fractures of the anterior cruciate ligament. Our simple method achieves strong, firm reattachment of the fracture. In addition, it prevents fixation loosening during suture tying effectively. Since pullout repair using nonabsorbable sutures is commonly used to fix various avulsion fractures, the tensioner helps attain strong, firm reattachment of avulsion fractures simply and effectively.  相似文献   
68.
Abstract: We have analyzed the plasma pharmacokinetics of busulfan in 272 patients receiving high-dose oral busulfan and intravenous cyclophosphamide in conjunction with allogeneic or autologous bone marrow transplantation. The patients ranged in age from 2 months to 59 yr (mean 10, median 12 yr) and had the following diagnoses: thalassemia or sickle cell anemia (n = 74); leukemia or myelodysplasia (n = 112); inborn errors of metabolism (n = 41) or immunodeficiency (n = 45). Plasma specimens were collected following the first dose for each patient which ranged from 1 to 4 mg/kg (mean ± SD, 1.21 ± 0.41, median 1.15). Busulfan was quantitated using ultraviolet absorbance detection after derivatization and HPLC separation. Pharmacokinetic parameters were derived by modeling the raw data to fit first-order single compartment kinetics. The kinetic parameters showed wide interpatient variability independent of age and diagnosis. There was a statistically significant correlation of age with the following parameters: area under the curve (AUC); maximal concentration; minimum concentration; clearance; volume of distribution and absorption half-time. The coefficients of determination (i.e. correlation coefficient squared) were low ranging from 0.04 to 0.12 implying only a small part (i.e. 4–12%) of the variance was explained by age. Although busulfan pharmacokinetics are age-related most of the variability is not explained by age or diagnosis.  相似文献   
69.
AMEDLINEsearchwasconductedtoidentifystudiespublishedfromJanuary1999toMarch2004thatcom-paredinjectablecalciumphosphatebone(NorianSRS)cementwithconventionaltreatmentindistalradialfrac-tures.Fromalistof13articlesidentifiedfromthesearchstrategy,fourarticleswe…  相似文献   
70.
The aim of this study was to fabricate an artificial bile duct for the development of a new treatment for biliary diseases. Eighteen hybrid pigs were implanted with a bile duct organoid unit (BDOU) made of a bioabsorbable polymer. Twelve of the transplanted BDOUs had been seeded with autologous bone marrow cells (BMCs) in advance. Six animals, the controls, were grafted with the scaffold alone with no BMCs seeded. The common bile duct was cut, the hepatic cut end of the native common bile duct was anastomosed to the BDOU and the other end was anastomosed to the duodenum. The controls underwent a similar operation. The neo-bile duct was removed at pre-determined time points and investigated histologically. All 18 recipient pigs survived until their sacrifice at 6 weeks, 10 weeks or 6 months. Histological examination revealed incomplete epithelialization of the neo-bile duct at 6 weeks and 10 weeks after transplantation. At 6 months, the organoid exhibited a morphology almost identical to that of the native common bile duct. No differences were found between the controls and BMC-seeded pigs. These results show that the artificial bile duct thus fabricated can serve as a substitute for the native bile duct.  相似文献   
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