神经化组织工程骨构建的初步观察

目的评估两种组织工程骨体内神经化重建方法的成骨效果,研究神经化与成骨的相互关系。方法26只新西兰大白兔,其中24只随机分成四组:组织工程骨组(A组),感觉神经束植入组(B组),运动神经束植入组(C组),血管束植入组(D组);另2只为空白对照组。每只动物均制备左侧股骨长1.5cm的段缺性骨与骨膜缺损,钢板固定后骨缺损处分别植入用四种方法制备的组织工程骨。植入的神经分别是隐神经和股神经肌支。术后4、8、12周摄股骨正位X线片,用放射影像学评分和X线阻射影分析比较骨缺损修复情况。结果在组织工程骨中植入感觉神经束后,比单纯组织工程骨和运动神经束植入的修复效果均有明显提高,而在组织工程骨中植入运动神经束与单纯组织工程骨修复骨缺损的效果相比较无明显差异,感觉神经束植入与血管束植入的成骨效果比较无明显差异,血管束植入组的成骨效果优于其它两组。结论利用感觉神经束植入的方法可以提高组织工程骨的成骨作用,而植入运动神经束却无此作用。     

软骨细胞诱导骨髓基质干细胞构建带内支撑的组织工程化软骨

目的 探讨以聚羟基乙酸(PGA)包裹特定形态的医用假体材料--多孔高密度聚乙烯(HDPE,商品名为MEDPOR)为支架,应用软骨细胞诱导骨髓基质干细胞(BMSCs),共培养构建特定形态的带内支撑组织工程化软骨医用假体的可能性.方法 以直径3 mm、长5 mm的圆柱形HDPE,外裹 1 mm厚PGA为支架,将体外分别培养的新生猪BMSCs和耳郭软骨细胞按7∶3混合,以10×10 7/ml细胞浓度接种于支架上,同时以相同浓度的单纯软骨细胞和单纯BMSCs分别接种,作为阳性对照组(PC组)和阴性对照组(NC组).经体外培养2周及在裸鼠皮下移植4、8周后取材 ,行大体观察、组织学、组织化学及免疫组化检测.结果 各组细胞均与材料黏附良好.实验组和阳性对照组均形成了大体形态良好的HDPE-软骨复合体,内支撑的HDPE与外层软骨结合紧密.组织学可见成熟的软骨陷窝结构,软骨渗入HDPE孔隙内部、异染基质及Ⅱ型胶原呈强阳性表达.结论 以HDPE为内支撑,外裹PGA的支架,接种混合细胞,可于皮下构建特定形态、组织学良好的HDPE-软骨复合体.     

短缩-延长肢体治疗胫骨骨缺损合并软组织缺损

目的探索单纯使用Orthofix重建外固定架通过短缩一延长肢体治疗胫骨骨缺损合并软组织缺损的可行性。方法2001年7月～2006年7月收治胫骨骨缺损合并软组织缺损患者39例，其中37例为胫骨感染性骨折不愈合，2例为胫骨开放性骨折（GustiloⅢB型1例，Gustilo ⅢC型1例）。在患肢上安放Orthofix重建外固定架。清创术后小腿胫前内侧软组织平均缺损12cm（6～24cm），胫骨骨缺损平均9cm（4～22cm）。对胫骨骨缺损〈5cm的患者使用一期清创．腓骨截骨．胫骨缺损端加压。对22例胫骨缺损〉5cm的患者采用清创，腓骨截骨．短缩肢体〈5cm。对炎症局限、胫骨截骨部皮肤正常而且远离伤口的患者同期行胫骨截骨术，否则于1．0～1．5个月后二期行胫骨截骨术延长恢复肢体的长度。结果所有患者平均随访14个月（10～44个月）。骨缺损均得以重建，患肢肢体长度与健侧之差小于5mm，骨折愈合，无感染复发，创面均闭合。1例术后出现腓总神经麻痹，术后2个月恢复。4例胫骨缺损患者诉膝部疼痛。5例胫骨蠓损患者出现马蹄内翻足。2例胫骨缺损出现下胫腓分离。1例再骨折。结论使用Orthofix重建外固定架进行短缩．延长肢体是治疗胫骨骨缺损合并软组织缺损的有效方法，但应谨慎使用。对于软组织缺损少的小腿一期短缩的安全限度为3cm，最终短缩6cm。对于软组织缺损较大的急性胫骨开放骨折小腿一期可以短缩9cm。     

经皮双针囊内注射类固醇治疗小儿孤立性骨囊肿

目的探讨经皮双针囊内注射类固醇治疗小儿孤立性骨囊肿的疗效. 方法 1996年1月～2004年1月,对28例小儿孤立性骨囊肿,在X线透视下,将2根细的骨穿针或腰穿针分别自囊腔顶部和底部刺入骨囊肿内,抽去囊液,冲洗囊腔后注入类固醇. 结果 27例随访10～62个月,平均28个月,无并发症发生.根据Chigira等X线骨囊肿愈合评价标准,Ⅳ级20例,Ⅲ级5例,Ⅱ例1例,Ⅰ级1例,治愈率92.6%(25/27).25例骨囊腔愈合时间3～10个月,平均4.5个月. 结论经皮双针囊腔内注射类固醇适合于小儿孤立性骨囊肿,简单,安全,治愈率高.     

椎弓根固定结合椎体成形术治疗胸腰椎爆裂骨折

目的探讨椎弓根固定结合经椎弓根椎体内植骨行椎体成形术治疗胸腰椎爆裂骨折的疗效。方法采用椎管环形减压、短节段椎弓根螺钉系统固定结合经椎弓根椎体内植骨治疗胸腰椎爆裂骨折116例,其中93例获得随访。术前及术后随访行X线和CT检查,测量伤椎椎体中央高度值,比较植骨后椎体高度的恢复程度,同时观察植骨融合情况。采用配对t检验方法进行统计学分析。结果93例患者术后平均随访24.2个月,90%以上患者伤椎椎体高度恢复并维持良好,无塌陷。伤椎椎体中央高度值犤T12(3.14±0.41)cm,L1(3.33±0.34)cm犦与正常值犤(T12(3.26±0.38)cm,L1(3.47±0.61)cm)犦比较,差异无显著性意义(P>0.05)。未出现植骨操作引起的神经血管并发症。CT显示椎体内植骨块边缘模糊,融合良好,植骨块无吸收现象。结论后路椎管环形减压及内固定时,经伤椎椎弓根进行椎体内植骨行椎体成形术可恢复伤椎椎体高度,重建前、中柱的稳定性,预防术后椎体塌陷的发生。     

Warping of cross sections in the torsion of long bones with internal fracture fixation plates

Torsion of noncircular beams results in warping of each cross section. When noncircular cross sections are constrained to remain plane, the resulting shear stress distribution is different from what Saint Venant torsion (with warping) would predict. This has practical implications to the stress analysis of plated long bones subjected to torsional loadings. Analyses in which warping is not allowed predict incorrect stress fields in the plate and bone and overpredict the amount of stress shielding associated with fracture plate fixation.     

双头加压螺纹钉贴股骨距内固定治疗股骨颈骨折

在Ｘ光电视下采用双头加压螺纹钉贴股骨距内固定治疗新鲜股骨颈骨折４２例，随访平均２．５年，其中１６例随访３年以上，骨折愈合率９５．２％，骨折不愈合并股骨头缺血性坏死率４．７６％。认为加压螺纹钉贴股骨距内固定可使钉的受力由较大剪应力变为较大轴向力承受，减少骨折处的剪应力，并加压于骨折端能促进骨折愈合。具有操作简单、进钉准确、创伤小、固定牢靠、并发症少等优点。     

Prevention of early postmenopausal bone loss using low doses of conjugated estrogens and the non-hormonal,bone-active drug ipriflavone

Hormone replacement therapy is the optimal therapeutic choice for postmenopausal syndrome. While low doses of estrogens (0.3 mg/day of conjugated estrogens) can counteract neurovegetative menopausal symptoms, higher doses (0.625 mg/day of conjugated estrogens) are required to prevent bone loss in postmenopausal women. Experimental and clinical studies have shown that ipriflavone, a non-hormonal isoflavone derivative, is effective in the prevention and treatment of postmenopausal osteoporosis. The aim of the present investigation was to evaluate the efficacy and toler-ability of ipriflavone and very low doses of equine conjugated estrogens on bone loss in early postmenopausal women. Eighty-three healthy postmenopausal women (50.3±0.7 years) were enrolled for this 1-year multicenter study. All subjects were randomly allocated to receive: double placebo (n=24; group A), placebo plus conjugated equine estrogens 0.30 mg/day (n=31; group B) or conjugated equine estrogens 0.30 mg/day plus oral ipriflavone 200 mg tris in die at meals (n=28; group C), according to a double-masked design. Among women who completed the treatment period (valid completers), those of group A showed a progressive decrease in forearm bone density (FBD; measured by dual photon absorptiometry) that reached 1.7% after 12 months. The women in group B maintained their FBD in the first 6 months of treatment but, at the end of the study, showed a bone loss of 1.4% compared with basal values. By contrast, women in group C showed a significant increase in FBD after 1 year of treatment (+5.6%;p<0.01). Bothvalid completers andintention to treat analyses revealed a significant difference (p<0.05) between group A and group C over the study period. None of the treatments produced significant changes of biochemical markers of bone turnover, while hot flushes and other climacteric symptoms were significantly reduced after the sixth month of treatment in women receiving estrogens. Adverse events were generally mild, and did not differ among the groups. The results of this study suggest that low doses of estrogens combined with ipriflavone could represent a new therapeutic approach to the treatment of the postmenopausal syndrome.     

牛骨形成蛋白在骨不连中的临床应用

应用牛骨形成蛋白（ｂｏｖｉｎｅＢｏｎｅＭｏｒｐｈｏｇｅｎｅｔｉｃＰｒｏｔｅｉｎ简称ｂ－ＢＭＰ）成功的治愈１３例骨不连病人。经过１３个月～２９个月随访观察，效果较好。本组病人术前平均已做过１．５次手术。１３例病人中，有１２例被１次治愈。１例病人再次行内固定加用牛骨形成蛋白的植入也被治愈。骨形成蛋白的应用方式，采用同锻石膏复合后植入骨不连处。平均每个病人植入１００ｍｇＢＭＰ，１３例病人平均治愈时间为４．７个月。术后没有任何并发症。     

Ridge number density: A new parameter for in vivo bone structure analysis

An advanced analysis of the mechanical properties of bone should include information about the microarchitecture of cancellous bone in addition to its density. It has recently been shown that high-resolution quantitative computed tomography and magnetic resonance imaging have the potential to assess such information in a noninvasive way in patients. Both techniques, however, lack sufficient spatial resolution to image the individual trabeculae with true precision. In this work, a new parameter, Ridge number density (RND), is introduced. RND is a measure for the trabecular number, which can be extracted directly from high-resolution three-dimensional (3D) images of patients. We applied the RND technique to a test group of nine healthy, postmenopausal women measured repetitively with a high-resolution 3D peripheral quantitative computed tomography (3D-pQCT) system with 165 × 165 × 165 μm³ voxel size. Simultaneously with the RND determination, the trabecular bone density (TBD) was also assessed in the same volume of interest. The examination site was the distal radius. The intersubject variability of the measured test group was 10.5% for RND and 26.3% for TBD. The root mean square error between first and second examinations (midterm reproducibility) was 1.6% and 1.1%, respectively. RND is determined independently from TBD and pertains to the structure of the cancellous bone. As such, it might add crucial information in cases where bone mass or bone density measurements alone give ambigous results.