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1.
目的研究在下颌骨较大速率牵引成骨术(DO)中应用重组人骨形成蛋白(rhBMPs)对成骨的影响,探讨下颌骨较大速率DO的可行性。方法12只山羊双侧下颌骨行DO,山羊及左右下颌骨随机化分为实验侧、对照侧,一只山羊作为正常标本。术中预置牵开间隙3.5mm,实验侧应用rhBMPs,延迟期为3d,牵引速率为1.5mm/d,分3次牵引,延长幅度为20mm。3、5、7、12周行大体、X线、骨密度、生物力学和组织学观察。结果延长幅度达到20mm,自固定期3周开始观察,牵引间隙新骨的再生形成及成熟改建仍是连续的骨愈合过程。固定期5周时,大体及X线观察表明实验侧已形成良好的骨皮质连续性,密度近于正常骨,而对照侧牵引间隙中间区却存在骨不连或间隙存在。组织学显示DO过程仍然是膜内成骨,对照侧牵引间隙中央可见中央区纤维连接、软骨改变,周边区可见新骨组织形成。生物力学三点弯曲实验显示实验侧在5周时接近正常骨,与对照侧有显著差异。骨密度随时间递增,实验侧在各时间点均高于对照侧。本实验条件下在5周后拆除牵引器较为可靠。结论较大速率DO的骨再生形成也是一个连续的膜内成骨过程。rhBMPs在较大速率和较大幅度DO中的应用能够加速骨的再生和愈合速...  相似文献   

2.
[目的]观察人骨形态发生蛋白2基因修饰的自体骨髓间充质干细胞移植对兔胫骨牵张成骨新骨形成的促进作用。[方法]48只新西兰白兔随机摸球法分为3组。建立牵张成骨动物模型,在固定期第2 d,实验组于牵张间隙注射人骨形态发生蛋白2基因修饰的自体骨髓间充质干细胞;对照组注射等量自体骨髓间充质干细胞;空白组不注射任何物质。[结果]在固定期2周及6周实验组牵张区在大体观察、HE染色、X线观察方面成骨质量均好于对照组和空白组。12周后取牵张成骨区标本作骨组织骨密度和生物力学测定,结果显示实验组新生骨质量较高,骨愈合情况要优于对照组和空白组。[结论]骨形态发生蛋白2基因修饰的自体骨髓间充质干细胞移植能有效提高兔胫骨牵张成骨新骨形成质量。  相似文献   

3.
下颌骨牵引术治疗成人半面短小畸形一例   总被引:1,自引:0,他引:1  
牵引成骨技术(distraction osteogenesis,DO)是一项将骨切开后应用牵引装置缓慢牵拉,使牵引间隙中形成新骨,从而达到骨骼处长目的的技术。我们对1例成人复杂半面短小畸形患者进行上、下颌骨的同时牵引治疗,效果良好。  相似文献   

4.
目的观察经皮自体骨髓移植在骨缺损瘢痕组织内的成骨作用,探索治疗骨不连的新途径。方法选健康家兔18只,建立双侧桡骨中段骨及骨膜缺损1cm模型,6周后,实验侧(右)骨缺损区经皮注射自体红骨髓2ml,对照侧(左)骨缺损区经皮注射自身外周血2ml。在不同时间内进行X线片、组织学检查及新生组织钙、磷含量测定。临床应用经皮自体骨髓移植治疗骨不连15例,其中腕舟骨不连7例,肱骨不连3例,股骨不连2例,胫骨不连3例。骨不连时间为7~48个月,平均13个月。结果实验侧骨缺损区在骨髓注射后不同时间的X线片、组织学检查均显示新骨形成逐渐增多,钙、磷含量均高于对照侧。对照侧无成骨现象。临床应用的15例中,13例在5~9个月骨折愈合,2例未愈合。结论经皮自体骨髓移植在骨缺损瘢痕组织内有成骨作用,在临床上可作为治疗骨不连的方法,尤其适用于骨不连部位软组织条件差、不具备开放植骨的病例。  相似文献   

5.
几丁质膜引导兔桡骨缺损骨再生的实验研究   总被引:14,自引:0,他引:14  
采用引导骨组织再生原理进行长管状骨缺损修复实验。取兔10只,造成双侧桡骨8mm节段性骨缺损,一侧采用几丁质膜覆盖成管室状,另一侧作为空白对照。术后6周,对愈后情况进行X线及组织学检查,对照侧均呈骨不连,骨端圆纯、髓腔闭合,治疗侧在膜表面形成薄形骨痂使骨缺损取得愈合。结果表明,几丁质膜具有引导骨组织再生、防止骨不连作用。而膜管内骨痂稀少可能与膜管阻碍了一些成骨因子进入膜管内有关,在膜管中植入BMP,  相似文献   

6.
目的 观察猕猴牵张成骨术整复腭裂过程中,新骨组织形成与改建活动的特点,探讨新骨生成的规律.方法 建立猕猴腭裂动物模型,以牵张成骨术整复其腭部软硬组织缺损,以每天2次、每次0.4 mm的速率牵引,直至骨运送盘移动关闭裂隙后原位固定.分别于固定期第1、2、4、6、8、12及24周取材,每时相点3只实验动物.取材前6 d,实验组动物(21只)均肌肉注射四环素(30 mg/kg)标记.各组标本包埋切片行组织学及荧光标记观察.结果 与实验对照组及空白对照组(动物各2只,同法标记)对比.结果 实验组骨运送盘移动至裂隙对侧关闭缺损,牵开间隙内以膜内成骨方式原位成骨,成功整复腭部软硬组织缺损.牵张成骨术后固定期从1至24周逐渐延长,呈现出成骨-改建-成熟的动态变化过程:牵张区新骨形成的量及其钙化程度不断增加,与此同时,新骨组织亦呈现不断改建成熟的趋势,软组织随着新骨的形成不断地延伸,对照组裂隙无法自行修复.结论 应用牵张成骨术整复腭裂缺损,在良好的固定下,通过膜内成骨的方式,新骨不断的成熟和改建,直至成功修复软硬组织缺损.  相似文献   

7.
目的 研究内源性骨形态发生蛋白 (BMP)、β转化生长因子 (TGF - β)的来源、分泌规律以及对骨修复的作用。方法 家兔 36只 ,每只动物左侧胫骨为对照侧 ,环形切除胫骨中段骨膜长 3cm ,并于内侧行部分骨皮质剥脱术 ,长 2 6cm ,厚 1mm ,不暴露骨髓腔。右侧为实验侧 ,以同法处理后 ,辅以钻孔达骨髓腔。术后 3天及 1、2、4、6、8周分别随机处死 6只动物 ,取双侧胫骨 ,制作 5 μm厚的组织切片 ,进行BMP、TGF - βⅢ免疫组化染色。结果 BMP、TGF - βⅢ免疫组化染色显示 ,对照侧染色阴性 ,始终无骨痂形成。实验侧术后 3天染色呈阳性反应 ;术后 1周内源性BMP、TGF - βⅢ浓度达高峰 ,成骨能力增强 ;术后 6周阳性细胞消失 ,但随着骨重建过程增强 ,骨基质染色较深。结论 骨损伤后内源性BMP、TGF - βⅢ呈阶段性分泌 ,且对骨损伤的修复起着重要作用。  相似文献   

8.
目的 评价组织隔离法与机械活动法在建立兔胫骨萎缩型与肥大型骨不连模型中的作用方法将l2只体重为3~4.5kg的新西兰大白兔随机分成A、B两组,A组于胫骨中段截骨,两断端套接1cm硅胶管,单侧外固定器固定,保持两断端间距2mm,8周取出硅胶管,观察组织隔离法构建萎缩型骨不连模型的效果。B组于胫骨中段截骨后采用2枚1mm克氏针行髓内松动固定,被动活动断端200次/天,持续1个月,观察机械活动法构建肥大型骨不连模型的效果。结果 A组中所有动物在硅胶管取出后4周,无1例断端出现骨愈合表脱,X线片显示良好萎缩型骨不连的复制。B组中所有动物存6周内截骨端出现延迟愈合,部分伴有畸形.骨断端有人量肥大骨痂形成。结论 硅胶管组织隔离法是复制兔胫骨萎缩型骨不连模型的有效方法,而采用被动机械活动复制兔胫骨肥大型骨不连模型的方法尚需进一步研究。  相似文献   

9.
骨搬移治疗胫骨感染性骨不连   总被引:1,自引:0,他引:1  
目的分析骨搬移治疗胫骨感染性骨不连的临床疗效。方法2002年10月至2007年10月采用胫骨感染骨端清创、重建外固定支架加压固定及胫骨干骺端截骨骨搬移治疗胫骨感染性骨不连、纠正肢体短缩畸形45例。结果45例胫骨感染均得到一期控制,软组织缺损创面消灭,4例出现钉道感染;44例骨折愈合,1例骨折端再次形成骨不连;39例双下肢长度基本恢复一致,6例仍有1.5~3cm肢体短缩畸形存在,1例因截骨端提前愈合使肢体未能达到预期长度;术后截骨端骨延长2~9cm,平均延长6cm,无血管及神经损伤的症状出现;术后外固定支架固定6~12个月,平均8个月,所有病例延长区新骨组织形成良好。结论采用骨搬移治疗胫骨感染性骨不连,能达到一次手术兼顾控制骨端感染、消灭皮肤创面、骨折端不需植骨达到骨性愈合及均衡肢体长度的临床治疗作用,是治疗胫骨感染性骨不连的理想方法。  相似文献   

10.
目的研究生物衍生骨与骨髓基质干细胞(marrow stromal stem cells, MSCs)复合修复山羊胫骨缺损的血管化过程,了解其修复长段管状负重骨缺损的血管化情况. 方法制备生物衍生骨作为支架材料,培养、诱导MSCs作为种子细胞,二者在体外复合构建组织工程骨.20只山羊双侧胫骨中段制备成20 mm长的骨-骨膜缺损模型,采取自身左右侧对照,实验侧(右侧)缺损处植入组织工程骨,对照侧(左侧)植入单纯支架材料,采用钢板内固定.术后2、4、6及8周用墨汁灌注透明标本及血管面积图像分析方法观察血管化过程,组织学观察血管形成及成骨情况. 结果术后2、4周,实验侧血管形成较对照侧少(P<0.05);术后8周,两侧均完全血管化,差异无统计学意义(P>0.05).实验侧于术后6、8周新骨形成逐渐增加,材料降解吸收较对照组快;对照侧术后8周材料孔隙内仍无明显新骨形成. 结论生物衍生骨作为骨组织工程的支架材料,能够较快发生血管化;组织工程骨成骨能力较单纯支架材料强.  相似文献   

11.
The purpose of this study was to determine if low intensity pulsed ultrasound (LIPU) accelerated the maturation of regenerate bone when applied after distraction in a rabbit model. A mid-tibial osteotomy was performed in 26 New Zealand white rabbits and an external fixator applied anteromedially. After a seven day latency period, the tibiae were distracted 0.5 mm every 12 h for 10 days. Thirteen of the rabbits received LIPU for 20 min/day (treatment group) and 13 received sham LIPU (control group) from day 17 until sacrifice on day 37. Radiographs were taken weekly after distraction and the total and mineralized areas of the callus were measured. After sacrifice, dual-energy X-ray absorptiometry, torsional testing to failure, and histomorphometry were performed. Ultrasound-treated tibiae were a mean of 68.8 +/- 3.8% as stiff as and 68.2 +/- 6.0% as strong as the contralateral tibiae. Control tibiae were 78.7 +/- 7.0%, as stiff as and 70.2 +/- 7.9% as strong as the contralateral tibiae. The differences in stiffness and strength were not significant (p = 0.39 and 0.81, respectively) with the number of the animals tested in the study. The treatment group was 91.6% as dense as the contralateral side and the control group was 88.5% as dense as the contralateral side (p = 0.84). Radiographs revealed a significantly larger callus in the LIPU-treated tibiae at 1, 2 and 3 weeks after distraction compared to control tibiae (p < 0.01, 0.008 and 0.05, respectively). Histomorphometry revealed significantly less fibrous tissue in the LIPU-treated tibiae (p < 0.05) and a strong trend towards more bone in the LIPU-treated tibiae compared to controls (p = 0.06). LIPU was found to increase the size of the distraction callus and it might alter the composition of regenerate bone but it did not have a positive effect on the mechanical properties or density of regenerate bone when applied during the consolidation phase of distraction osteogenesis.  相似文献   

12.
Distraction osteogenesis is used both for leg lengthening and for bone transportation in the treatment of fractures and nonunions. The main problem with this method is that the time until full recovery may be up to a year, partly because of the time needed for the new formed bone to consolidate and become strong enough for weight bearing. We have studied whether intermittent parathyroid hormone (PTH(1-34)) could accelerate the consolidation of new formed bone after distraction osteogenesis in rats. Forty-seven, 3-months-old male Sprague-Dawley rats underwent lengthening of the right femur using an external fixator. After a middiaphyseal osteotomy and a 7-day latency period, the callus was distracted during 10 days, with a distraction rate of 0.25 mm twice a day. The consolidation time was either 20 days or 40 days after distraction was completed. A dose of 60 microg of human PTH(1-34)/kg body weight/injection or vehicle was given every second day beginning 30 days before the rats were killed. Both femura of each rat were subjected to mechanical testing and dual-energy X-ray absorptiometry. Blinded histological examination was done for the distracted femura. In the 20 days consolidation experiment, PTH(1-34) increased ultimate load (56%), stiffness (117%), total regenerate callus volume (58%), callus BMC (24%) and histologic bone density (35%) compared to untreated distraction osteogenesis specimens. In the 40 days consolidation experiment, PTH(1-34) increased ultimate load (54%), stiffness (55%), callus BMC (33%) and histologic bone density (23%) compared to untreated distraction osteogenesis specimens. Total regenerate callus volume was unchanged. The contralateral femur also became stronger, stiffer and denser under PTH(1-34) treatment, but to a lesser degree. PTH(1-34) might become useful to shorten the consolidation time after distraction osteogenesis in humans.  相似文献   

13.
Angiogenesis is essential for wound healing and proliferative processes such as bone formation and repair. Since increased expression of the vascular endothelial growth factor (VEGF) stimulates bone formation, it can be hypothesized that surgical procedures leading to a systemic increase of VEGF for instance during wound healing, influence enchondral ossification processes and might be responsible for observed growth phenomena during callus distraction. To study the mechanisms of angiogenesis in soft tissue during unilateral callus distraction, lengthening of the right tibia was performed in 12 beagles. After osteotomy, application of a ring fixator and after five latency days, distraction was started for 25 days. A control group of four additional beagles underwent no surgical procedure. Subsequent to the distraction period (Group A), muscle samples from six beagles were taken from the distracted side (ds) and the contralateral non-distracted side (n-ds), six beagles underwent an additional consolidation period of 25 days (Group B). Samples were analyzed for VEGF, VEGFR-1 and VEGFR-2 mRNA expression using real-time PCR and protein expression using Western Blot analysis. Muscles from both extremities showed significantly increased expression of VEGF and its cognate receptors VEGFR-1/2. Expression decreased significantly after the consolidation period, whereby the level at the non-distracted side decreased more than the level at the distracted side. Interestingly VEGF and VEGFR-1 levels at the non-distracted side were significantly higher than at the distracted side. In contrast VEGFR-2, the receptor that mediates endothelial cell proliferation, showed higher levels at the distracted than at the non-distracted side. These findings indicate that callus distraction results not only in locally increased expression of VEGF and its receptors, but leads also to increased VEGF and VEGFR-1/2 levels at distant sides and might therefore be responsible for the observed growth phenomena during callus distraction.  相似文献   

14.
Background Distraction osteogenesis can be used for the treatment of osteomyelitis and nonunion, conditions thought to benefit from increased blood flow in the bone tissue of the distracted limb. We have questioned whether such an increase occurs, and investigated the spatial distribution of bone blood flow after distraction osteogenesis.

Methods The tibiae of 8 rabbits were lengthened 10 mm by a standard midtibial distraction osteogenesis procedure. 2 weeks into the consolidation phase, the bone and soft tissue blood flow of the distracted and the contralateral extremity were measured using radioactive microspheres.

Results The absolute bone blood flow of the distracted tibia was 4% lower than that of the non-distracted side, representing a 41% decrease in the proximal metaphysis, a smaller decrease in the proximal epiphysis, distal metaphysis and distal epiphysis, and an increase in the diaphysis.

Interpretation Mid-tibial distraction osteogenesis redistributed the bone blood flow of the distracted tibia, but absolute tibial blood flow did not increase. Our results do not confirm previous research in this field.  相似文献   

15.
《Acta orthopaedica》2013,84(4):459-464
Background Distraction osteogenesis can be used for the treatment of osteomyelitis and nonunion, conditions thought to benefit from increased blood flow in the bone tissue of the distracted limb. We have questioned whether such an increase occurs, and investigated the spatial distribution of bone blood flow after distraction osteogenesis.

Methods The tibiae of 8 rabbits were lengthened 10 mm by a standard midtibial distraction osteogenesis procedure. 2 weeks into the consolidation phase, the bone and soft tissue blood flow of the distracted and the contralateral extremity were measured using radioactive microspheres.

Results The absolute bone blood flow of the distracted tibia was 4% lower than that of the non-distracted side, representing a 41% decrease in the proximal metaphysis, a smaller decrease in the proximal epiphysis, distal metaphysis and distal epiphysis, and an increase in the diaphysis.

Interpretation Mid-tibial distraction osteogenesis redistributed the bone blood flow of the distracted tibia, but absolute tibial blood flow did not increase. Our results do not confirm previous research in this field.  相似文献   

16.
OBJECTIVES: The aim of the current study was to analyze distraction osteogenesis histomorphometrically to investigate the amount of enchondral ossification adjacent to intramembranous ossification. STUDY DESIGN: Species-specific, longitudinal time study.METHODS Lengthening of 25% of the right tibia was performed in 24 beagle dogs by callus distraction after osteotomy and application of a ring fixator. Distraction was started at the fifth postoperative day with a distraction rate of 0.5 mm twice a day. Twelve dogs were killed at the end of the distraction phase of 25 days (group A) and the remaining 12 dogs after an additional consolidation period of 25 days (group B). The tibia was removed from the distracted right leg and from the left control side of each animal, and longitudinal sections were cut and stained with Pentachrome. In all tibiae, an area of 0.5 x 2.4 cm within the endosteal bone was evaluated histomorphometrically with a Merz grid, and the results were compared between distraction and control side as well as between the dogs of group A and group B. RESULTS: On the distraction side, the typical signs of an increased de novo bone formation with a significant increase of osteoblasts and osteoid in group A, as well as an additional significant increase of bone volume and trabecular thickness in group B, were found. In all distraction cases, islands of cartilage formation, which underwent enchondral ossification, were found, besides membranous ossification. The ratio between membranous and enchondral ossification was found to be five to one. CONCLUSION: Bone formation during distraction osteogenesis results from both membranous and enchondral ossification.  相似文献   

17.
Distraction osteogenesis is widely used in treating deformities, defects, and fractures of both long bones and craniofacial bones. Demands for acceleration of bone consolidation are increased in distraction osteogenesis. Nerve growth factor (NGF) can enhance innervation and bone regeneration in a fracture model and stimulate differentiation of osteoblastic cells. In this study, we tested the ability of locally applied NGF to enhance bone regeneration in a rabbit model of mandibular distraction osteogenesis. Twenty rabbits underwent bilateral distraction osteogenesis with a rate of 0.5 mm per 12 h. Two times 0.04 mg human NGFbeta (hNGFbeta) in buffer was injected into the callus after distraction. The contralateral side received placebo injections. Rabbits were euthanized at consolidation times of 14 and 28 days. Specimens were subjected to radiography, callus dimensions measurement, mechanical testing, and bone histological and histomorphometric analysis. The maximum load, bone volume/total volume, mineral apposition rate of the 1st to 11th day, and mineralized bone percentage were significantly higher in the hNGFbeta side at 14 and 28 days (p<0.05). The data indicate that locally applied hNGFbeta can accelerate callus maturation and may be an option to shorten the consolidation period in distraction osteogenesis.  相似文献   

18.
Bone injuries have a systemic influence on the remodeling of bone. This effect has not been examined concerning its extent and duration. We measured the systemic effect of distraction osteogenesis on the remodeling of bones of the axial skeleton by means of the mineral apposition rate and bone formation rate in an animal experiment. Distraction osteogenesis was performed on the tibiae of 24 mature Yucatan minipigs. After a 4-day latency period, the tibiae were distracted 2 mm/day for 10 days. The ensuing consolidation phase lasted 10 days. Three fluorescent labeling substances were applied intravenously: calcein green at the second postoperative day, tetracycline 1 day after the end of the distraction phase, and xylene orange 2 days before sacrifice. We prepared ground sections from the ninth right ribs. The mineral apposition rate and bone formation rate were measured histomorphometrically on labeled osteons. The median mineral apposition rate during distraction was 2.39 μm/day (2.12–2.62 μm/day), which was higher than the rate during consolidation (median, 1.62 μm/day; 1.54–1.84 μm/day). The median bone formation rate confirmed this result and was 840.51 μm2/day (744.20–1148.26 μm2/day) during distraction and 384.25 μm2/day (330.84–467.71 μm2/day) during consolidation. Thus, a short period of distraction osteogenesis appears to have an anabolic effect on the mineral apposition rate of remote cortical bone.  相似文献   

19.
To study the effect of applying pulsed electromagnetic fields (PEMF) during the consolidation phase of limb lengthening, a mid‐tibial osteotomy was performed in 18 adult New Zealand White rabbits and an external fixator was applied anteromedially. Animals were randomly assigned to treatment and control groups. After a 7‐day latency period, the tibiae were distracted 0.5 mm every 12 h for 10 days. The treatment group received a 20‐day course of PEMF for 60 min daily, coinciding with initiation of the consolidation phase. The control group received sham PEMF. Radiographs were performed weekly after distraction. Animals were euthanized 3 weeks after the end of distraction. Radiographic analysis revealed no significant difference in regenerate callus area between treatment and control tibiae immediately after distraction, at 1 week, 2 weeks, or 3 weeks after distraction ( p = 0.71, 0.22, 0.44, and 0.50, respectively). There was also no significant difference in percent callus mineralization ( p = 0.96, 0.69, 0.99, and 0.99, respectively). There was no significant difference between groups with respect to structural stiffness ( p = 0.80) or maximal torque to failure ( p = 0.62). However, there was a significant positive difference in mineral apposition rate between groups during the interval 1–2 weeks post‐distraction ( p < 0.05). This difference was no longer evident by the interval 2–3 weeks post‐distraction. While PEMF applied during the consolidation phase of limb lengthening did not appear to have a positive effect on bone regenerate, it increased osteoblastic activity in the cortical bone adjacent to the distraction site. Since the same PEMF signal was reported to be beneficial in the rabbit distraction osteogenesis when applied during distraction phase and consolidation phase, application of PEMF in the early phase may be more effective. Further work is necessary to determine optimal timing of the PEMF stimulation during distraction osteogenesis. © 2005 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res  相似文献   

20.
Clinical results of distraction osteogenesis with transplantation of marrow-derived mesenchymal stem cells (MSCs) and platelet-rich plasma (PRP) were reviewed in three femora and two tibiae of the two patients with achondroplasia and one patient with congenital pseudarthrosis of the tibia. MSCs derived from the iliac crest were cultured with osteogenic supplements and differentiated into osteoblast-like cells. PRP, which is known to contain several growth factors and coagulate immediately by a minute introduction of thrombin and calcium, was prepared just before transplantation. Culture-expanded osteoblast-like cells and autologous PRP were injected into the distracted callus with the thrombin-calcium mixture so that the PRP gel might develop within the injected site. Transplantation of MSCs and PRP was done at the lengthening and consolidation period in each patient. The target lengths were obtained in every leg without major complications and the average healing index was 23.0 days/cm (18.8-26.9 days/cm). Although these results are still preliminary, transplantation of osteoblast-like cells and PRP, which seemed to be a safe and minimally invasive cell therapy, could shorten the treatment period by acceleration of bone regeneration during distraction osteogenesis.  相似文献   

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