髓内钉在矫治儿童成骨不全严重肢体畸形中的应用

[目的]探讨用髓内钉治疗儿童成骨不全严重肢体畸形中的矫形和防止再骨折的作用。[方法]2000年1月-2004年8月期间，共治疗8例，男3例，女5例。术中均将弯曲股骨或胫骨行多段截骨后髓内钉固定。其中2．0mm克氏针置入2例，Ender钉3例，Nancy弹性髓内钉3例。[结果]术后8例畸形改善明显，随访9个月．5a，平均2．4a，随访中肢体未再发骨折，未见髓内针合并感染、骨不连等并发症。1例术前轮椅患儿术后可扶拐行走；1例发生克氏针骨外部分断裂。[结论]多段截骨矫形后内置髓内钉治疗儿童成骨不全，对矫正肢体畸形、减少再次骨折机会，效果确实可靠。     

rhBMPs对山羊下颌骨较大速率DO成骨的影响

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...     

脂肪干细胞/Ⅰ型胶原凝胶复合体的构建及其体内外成骨分化研究

目的探讨利用脂肪干细胞与Ⅰ型胶原凝胶复合构建新型骨组织工程复合体的可行性并对其体内外成骨分化情况进行分析。方法取3月龄日本大耳白兔肩胛部皮下脂肪，Ⅰ型胶原酶消化获得细胞，于体外依次进行骨、软骨、脂肪多向诱导分化鉴定；取第3代细胞与Ⅰ型胶原凝胶复合，于成骨诱导条件下体外培养，相差显微镜、扫描电镜观察复合情况并对其碱性磷酸酶、细胞外基质矿化程度进行检测，同时设立单层贴壁培养细胞作为对照（n=4）；两周后移植于裸鼠皮下，12周后处死动物，依次行放射学、组织学检测观察成骨情况（n=3）。结果（1）所获细胞具备骨、软骨、脂肪多向分化潜能，为多能干细胞。（2）形态学观察显示脂肪干细胞呈三维立体生长状态，均匀、高密度悬浮于Ⅰ型胶原凝胶中。在体外成骨诱导条件下，其碱性磷酸酶活性以及外基质矿化程度均显著高于单层贴壁培养细胞（P〈0．01，n=4）。（3）于裸鼠皮下移植12周后，放射学、组织学检测显示脂肪干细胞．Ⅰ型胶原凝胶复合体成骨明显（n=3）。结论（1）IⅠ型胶原凝胶可显著促进脂肪干细胞的成骨分化。（2）作为一种新型的骨组织工程复合物，脂肪干细胞-Ⅰ型胶原凝胶复合体可应用于骨组织工程，特别是腔隙性骨缺损的修复过程。     

Cytotoxic agents are detrimental to bone formed by distraction osteogenesis

Distraction osteogenesis can be used to replace segmental bone loss when treating malignant bone tumors in children and adolescents. These patients often receive cytotoxic chemotherapy as part of their treatment regimen. The effect of cytotoxic drugs on the cellular processes during distraction osteogenesis and the structural and mechanical properties of regenerate bone is unknown. We therefore used a rabbit model of distraction osteogenesis to determine that cytotoxic agents had a detrimental effect on regenerate bone formed by this technique. We administered adriamycin and cisplatinum to 20 rabbits using two different simulated chemotherapy regimens. All rabbits underwent an osteotomy at 12 weeks of age. Distraction osteogenesis began 24 h later at a rate of 0.75 mm a day for 10 days, followed by 18 days without correction to allow for consolidation. Regenerate bone was assessed using plain radiographs, bone densitometry, and mechanical testing. Peri-operative chemotherapy decreased the mechanical properties of the regenerate with regard to yield strain (3.7 × 10⁻² vs. 5.2 × 10⁻²) and energy at yield (2.73 × 10⁷ vs. 3.92 × 10⁷). Preoperative chemotherapy in isolation reduced bone mineral density (0.38 vs. 0.5 g/cm²), bone mineral content (0.24 vs. 0.36 g), and volumetric bone mineral density (0.57 vs. 0.65 g/cm²) with no alterations in the mechanical properties. Conclusions: Preoperative chemotherapy appears to decrease the volume of regenerate bone, without affecting structural integrity, suggesting that the callus formed is of good quality. The converse appears true for peri-operative chemotherapy.     

An iatrogenic proximal radioulnar synostosis: a case report and review of literature

The most common cause of proximal radioulnar synostosis in adults is traumatic, usually after forearm fractures. Disabling complications are mainly loss of rotatory movements of the forearm. Various surgical procedures have been described in the literature to end up in forearm synostosis as a complication. We here presented a rare case of proximal forearm synostosis following a common but improper surgical technique for an olecranon fracture complicated by implant infection. The synostosis was treated by resection and fascia lata interposition graft.     

体外诱导成纤维细胞成骨活性表达的研究

目的探讨成纤维细胞(fibroblast,FB)体外成骨表达的诱导因素,为其能否成为骨组织工程的种子细胞提供理论依据.方法分离和纯化新西兰兔肉芽组织FB,按1×105/ml分别接种于含纤维结合蛋白(fibronectin,FN)10、20、40、60、80μg/ml条件培养液中(实验1～5组),对照组为不含FN的无血清培养液.于培养14 d后,行细胞组织学观察及钙化结节形成率、趋骨性四环素荧光标记、3H-TdR标记、骨钙素测定及3H脯氨酸标记,检测FB成骨表型表达的标志.结果组织学观察实验组发现FB由梭形逐渐趋向多突形和圆形,细胞核偏向一侧,细胞重叠成多层结构;其表面有钙盐堆积,逐渐呈云雾状物质,经不断融合和扩大形成不透光的结节.干预培养14 d钙化结节形成率:对照组15.35%±3.45%,实验1～5组分别为53.73%±9.49%、75.21%±9.80%、98.34%±15.20%、61.83%±10.04%、45.11%±8.70%,实验组与对照组比较,差异有统计学意义(P＜0.05);实验3组与其它各实验组比较,差异有统计学意义(P＜0.05).趋骨性四环素特异性标记为新生骨组织;FB增殖活性,实验3、4、5组7 d时,实验2、3、4组14 d时与对照组比较,差异有统计学意义(P＜0.05).实验1～5组FB分泌骨钙素,实验2～5组3H-脯氨酸掺入量高于对照组,7、14d时与对照组比较差异有统计学意义(P＜0.05).结论适量的FN可以促进FB增殖、胶原蛋白的合成及骨钙素分泌,FN可以诱导FB成骨表达,适宜浓度为40～60μg/ml.     

负载重组人骨形态发生蛋白-2壳聚糖纳米微球的制备及异位成骨活性研究

目的 制备负载重组人骨形态发生蛋白-2(rhBMP-2)的壳聚糖纳米微球,并考察其成骨活性. 方法 应用离子交联法制备空白壳聚糖纳米微球和rhBMP-2壳聚糖纳米微球,应用透射电镜观察微球的形态,激光粒径分析仪测定其粒径的分布,检测其载药量、包封率及累积释药率.取24只SD大鼠,随机分为4组,每组6只.以无菌手术分别在大鼠左侧股部建立肌袋.A组大鼠肌袋内植入rhBMP-2壳聚糖纳米微球(含rhBMP-2 1 mg),B组大鼠肌袋内植入rhBMP-2 1 mg,C组大鼠肌袋内植入空白壳聚糖纳米微球,D组大鼠肌袋内不做任何处理.评估rhBMP-2壳聚糖纳米微球的成骨活性.结果离子交联法制备的壳聚糖纳米微球球形规整、分散均匀,微球平均粒径为230.0 nm,分布较集中,包封率为66.87％±4.58％,载药率为(33.44±2.29) μg/mg.A、B、C、D组的ALP活性平均分别为(1.94±0 35)、(1.48±0.56)、(0.20±0.07)及(0.18±0.06) kat/g,差异有统计学意义(F=42.959,P=0.000),A、B组明显高于C、D组,且A组高于B组.4组钙含量平均分别为(5.20±1.42)、(3.80±1.40)、(0.19±0.08)、(0.20±0.08)μg/mg,差异有统计学意义(F=39.242,P=0.000),A、B组明 显高于C、D组,且A组高于B组. 结论 离子交联法可成功制备出均一的rhBMP-2壳聚糖纳米微球,该微球具有良好的载药性能和缓释性能,且其骨诱导活性优于单纯rhBMP-2.     

转染骨形态发生蛋白-2基因的人骨髓间质干细胞复合异种骨支架异位成骨的效果

目的 观察骨形态发生蛋白-2(BMP-2)罐因转染的人骨髓间质干细胞复合异种骨支架异位成骨效果。方法 分组：(1)BMP-2基因转染细胞 异种骨支架[去抗原牛松质骨(BCB)]；(2)对照基因转染细胞 BCB；(3)未转染细胞 重组BMP-2 BCB；(4)未转染细胞 BCB；(5)BCB。分别将各组人工骨植入裸鼠皮下，于术后4，8周行组织学观察．结果 体内植入后3d，细胞持续表达外源基因BMP-2基因转染组8周时完全由新形成的编织骨构成，血管丰富。结论 BMP-2基因转染后细胞复合BCB支架，可以在异位形成骨组织并诱导毛细血管长入。     

Early bone reformation after cranial vault remodelling for sagittal craniosynostosis: A retrospective 3D analysis

This study aims to measure postoperative bone reformation percentage, rates and patterns after cranial vault remodelling (CVR) in isolated non-syndromic sagittal craniosynostosis. Volumetric bone measurements were performed starting from the DICOM files of previously available postoperative CT scans. The 3D images were then resampled into the master box, and ‘Skull 3D models’ were derived. The percentage of bone reformation was investigated using automated 3D analysis software. The intra-rater reliability analysis revealed high reliability (Intraclass correlation coefficient = 0.99, p < 0.001). The median bone reformation volume and rate were 11.2 ml and 1.98 ml/week, respectively. The median percentage of bone reformation was 56.7% when the median postoperative CT timing was 6.1 weeks. As a statistic model, the linear plateau showed the highest Pseudo R² in both volume and percentage of bone reformation predicting patterns. By using the calculated model at 9 weeks postoperatively, the re-osteogenesis reaches 80% of the total cranial defect. After CVR, the early bone reformation pattern was demonstrated as a linear plateau model rather than logarithmic. This study gives a better understanding of the pattern and quantity of re-osteogenesis at cranial defects after CVR. The statistic model can facilitate healthcare practitioners to predict bone reformation and improve postoperative care protocol in sagittal craniosynostosis management.     

Cochlear implantation in a patient with osteogenesis imperfecta

Osteogenesis imperfecta (OI) is a connective tissue disorder characterized by a deficit in the synthesis of type I collagen. Hearing loss affects 42–58% of OI patients and progresses to deafness in 35–60% of these patients. For OI patients, cochlear implantation (CI) is the only promising treatment option. However, literature on CI in patients with OI is relatively rare. After CI, speech perception is generally good. However, among patients with severe demineralization of the cochlea, most patients are reported to have complications of facial nerve stimulation (FNS), preventing some patients from using the cochlear implant on a daily basis. Here we report a successful CI using a Nucleus CI24 Contour Advance cochlear implant in a patient with OI. Although high-resolution computed tomography (HRCT) showed extensive demineralization of the cochlea, intracochlear electrodes were inserted properly. The use of a modiolus-hugging device and the advance off-stylet technique contributed to the successful implantation, with no complications such as FNS or misplacement of electrodes. Therefore, CI can be used for treating deaf patients with OI.