Improved Performance of Hip DXA Using a Novel Region of Interest in the Upper Part of the Femoral Neck: In Vitro Study Using Bone Strength as a Standard of Reference

We tested the hypothesis that bone mineral density (BMD) and bone mineral content (BMC) in proximal human femur specimens in the upper neck region of interest (ROI) and femoral neck axis length (FNAL) provide a significantly better prediction of femoral bone strength than standard ROIs in vitro. BMD and BMC were measured in 110 proximal femur specimens using a standard dual-energy X-ray absorptiometry (DXA) scanner. The analysis included a new ROI in the upper neck as well as the standard ROIs. FNAL was obtained from the scan images. The specimens' failure-load was measured in a mechanical loading device, simulating a fall on the greater trochanter. For the standard ROIs, correlations between failure-load and BMD ranged from R2 = 0.64 (shaft ROI) to R2 = 0.70, p < 0.001 (femoral neck). Prediction of strength by BMD did not significantly differ from those of BMC (R2 ranging from 0.65 to 0.75, p < 0.001). In the upper neck ROI, for both BMD and BMC correlations with failure-load were higher (R2 = 0.76 and 0.81, respectively; p < 0.001). A lower, yet still significant, correlation was found between FNAL and bone strength (R2 = 0.23, p < 0.001). Normalization of failure-load with respect to FNAL did not significantly increase the correlations with densitometric measures. This study provides in vitro evidence indicating that among the ROIs of the proximal femur the newly defined upper neck ROI provides the best prediction of bone strength. Only a weak association was observed between failure load and FNAL.     

按压骨穴调节围绝经期妇女心脏植物神经功能的研究

目的观察按压骨穴对围绝经期妇女心脏植物神经功能的影响。方法设按压骨穴组30例、空白对照组30例。用美国BraemarDL700型动态心电检测仪,检测试验前后的心率变异性(HRV):TF代表总频,LF代表交感神经活性,HF代表迷走神经活性,LF/HF代表交感神经与迷走神经均衡性。结果按压骨穴后4项指标均有显著下降(P<0.01,P<0.05)。空白对照组变化不显著(P>0.05)。骨穴组4项指标的变化率与对照组比较均有显著性差异(P<0.01)。结论按压骨穴有抑制心脏交感神经活性的良性调整作用,此效应具有相对的特异性。     

新生儿骨矿质含量及影响因素的研究

应用双光子及单光子吸收测定技术，检测了９２名出生３ｄ内的新生儿骨矿质含量，其中巨大儿３０名，正常体重儿３２名，低出生体重儿３０名，其孕龄分别是４０．１±０．７、３９．１±１．５和３７．４±１．２孕周。结果表明，巨大儿、正常体重儿、低出生体重儿的全身骨矿质含量分别是１０１．６±２８．８、８５．２±１９．８、５９．９±２７．２ｇ／ｃｍ２，巨大儿骨矿质含量最高，正常体重儿次之，低出生体重儿最低，差异有显著性（Ｐ＜０．０１）。颅骨、肱骨、股骨的骨矿质含量与全身的骨矿质含量有高度的相关性，相关系数分别是０．９４３、０．８７９和０．７４５（Ｐ＜０．０１）。全身的骨矿质含量与出生体重、孕龄及头围有高度相关性，相关系数分别是０．７５５、０．５９６和０．５５６（Ｐ＜０．０１）。提示颅骨、肱骨及股骨的任一部位均可代表全身的骨矿质含量，肱骨是确定全身骨矿质含量较好的部位，新生儿骨矿质含量受出生体重、孕龄及头围的影响较大。     

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.     

颞耳岩锥长轴方向的确定和应用

用头颅表面两个标志点确定岩锥长轴方向，指导梅氏（Ｍａｙｅｒ）位和斯氏（Ｓｔｅｎｖｅｒｓ）位摄影操作。对１２０例正常头颅ＣＴ图像进行测量，进行统计学处理，确定正常人岩锥长轴前延长线与头颅表面交点的大概位置。结果为：岩锥长轴前延长线交于对侧听眦线外眦后０．８２～２．９０ｃｍ区间，平均值左为１．６６ｃｍ，右为１．８２ｃｍ。结论，以平均值的邻值２ｃｍ为常数，即对侧听眦线外眦后２ｃｍ为岩锥长轴前延长线的前端体表定位标志，与其后端的乳突最突点共同确定岩锥长轴方向。     

胎骨移植治疗骨肿瘤缺损：附10例报告

近3年来，用制备的胎骨充填良性骨肿瘤及病样病变术后骨缺损，经观察10例效果良好。胎骨因其自身组织学和生理学特点，具有抗原性小、诱导成骨活性高，利于“爬行各代”等优点。而且来源丰富、采制简单、储存容易、费用低度，是一种良好的植骨材料，特别适于儿童及年老体弱患者自身取骨困难的骨缺损植骨需要。但其为异体骨，有一定免疫原性，抗支撑强度略差，应注意严格无菌操作、消除免疫原性、配合使用内、外固定等措施。     

CT and MRI of the middle ear

Summary High-resolution computed tomography (HRCT) provides excellent contrast between osseous structures, air and soft tissue in conjunction with high spatial resolution. Therefore, thin-section HRCT with bone window setting is the method of choice for the examination of the middle ear structures. The indications are acute and chronic inflammatory changes, cholesteatoma and tumor, the “postoperative middle ear”, and malformations. In most cases, HRCT enables differentiation between inflammatory changes, cholesteatoma, and tumor. The excellent depiction of subtle osseous details enables the identification of erosions of the ossicles or of the bony walls of the mastoid cells, of osseous defects of the tegmen, of the bony labyrinth, and of the tympanic course of the facial canal. In addition, HRCT enables excellent depiction of reconstructions of the ossicles or prosthesis of the ossicles. Although HRCT is the first method of choice, magnetic resonance imaging (MRI) may provide additional information and lead to a more accurate diagnosis in some cases. This is explained by the excellent soft tissue contrast provided by MRI. In addition, MRI offers the possibility of using various pulse sequences and the administration of IV contrast material. Therefore, MRI may allow the differentiation between inflammatory changes, cholesteatoma, and tumor in those cases in which accurate diagnosis cannot be made by HRCT. The differentiation between a meningocele or meningoencephalocele and other entities such as tumors or cholesteatoma can be established by MRI. Furthermore, MRI can accurately depict cases of labyrinthitis or of neuritis of the facial nerve or of intracranial disease caused by middle ear processes, while this is not always possible by HRCT. In summary, HRCT of the middle ear is the method of choice, but MRI may provide supplementary information in those cases in which accurate diagnosis cannot be established by HRCT.      

Volume of tarsal bones in congenital clubfoot

To elucidate the growth of the tarsal bones in congenital clubfoot, relative to the growth of these bones in the unaffected feet and compared to growth in the feet of normal volunteers, we used a computed tomography (CT) scanner to measure the volume of all tarsal bones. The subjects of the study were 10 adults (7 men and 3 women) with unilateral congenital clubfoot (average age 20 years and 1 month). As controls, we examined 11 healthy volunteers. We calculated the ratio of the volume of each tarsal bone to the total bone volume and the ratio of the volume of each tarsal bone in clubfoot to the corresponding bone in the unaffected foot. The volume ratio of each tarsal bone was compared between clubfeet and unaffected feet because the differences of each tarsal bone ratio between the normal foot group and unaffected foot group were not significant. In the clubfeet (n=10), the talus and the medial cuneiform bones were smaller than those in the unaffected feet (n=10) but the cuboid bone was larger. The growth of the navicular did not differ from as that in unaffected feet. Our results suggested hypoplasia on the medial side of the foot in adult patients with congenital clubfoot. The 3 patients who had undergone medial release showed particularly marked hypoplasia of the medial side. In congenital clubfoot cases with severe deformities who had undergone wide soft-tissue release operations, there were clear growth suppressions in the talus and the medial cuneiform. We could not determine whether the cause of the growth suppression was the hypoplastic nature of tarsal bones themselves or the surgical obstacles to tarsal bone growth.     

Treatment of labial fenestration of maxillary central incisor

Abstract A case of external inflammatory root resorption and labial fenestration in a maxillary central incisor is presented. The root canal was dressed with pure calcium hydroxide mixed with normal saline for 1 month before it was obturated with gutta percha and apicoectomy surgery undertaken to attempt primary closure of the fenestration. The PDL and the fenestration healed uneventfully.     

骨髓间质干细胞体外预构组织工程化肌腱的实验研究

目的探讨骨髓间质干细胞与胶原-聚羟基乙酸的细胞相容性,为构建组织工程化肌腱寻求理想方法.方法以贴壁法分离、培养骨髓间质干细胞,并检测CD44.在实验组中将骨髓间质干细胞置入含胶原-聚羟基乙酸的DMEM培基中培养:在对照组中将骨髓间质干细胞置入DMEM培基中培养.通过MTT方法比较两组的细胞活性和生长情况,并对实验组进行超微观察.以骨髓间质干细胞为种子细胞,以胶原-聚羟基乙酸为支架在体外预构组织工程化肌腱.结果以贴壁法原代培养骨髓间质干细胞,11天细胞即汇合成片,检测CD44示阳性.骨髓间质干细胞接种于胶原-聚羟基乙酸中混合培养后14天生长良好,始终保持89%以上的细胞活力,与对照组比较无显著差别;实验组细胞数未发生明显改变,而对照组从第4天开始即发生增殖.透射电镜示实验组细胞培养14天后仍保持旺盛的分泌功能.体外预构的组织工程化肌腱具有良好的形态,细胞伸展成梭形,沿聚羟基乙酸缝线大致平行排列.结论骨髓间质干细胞与胶原-聚羟基乙酸的细胞相容性好.以骨髓间质干细胞为种子细胞,以胶原-聚羟基乙酸为支架可在体外初步预构组织工程化肌腱.