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1.
《Gait & posture》2022
BackgroundMedical and surgical interventions to prevent or reduce bone deformities and improve gait in children with cerebral palsy (CP) are based on empirical evidence that there is a relationship between bone deformities and gait deviations.Research questionWhat is the relationship between tibial-femoral bone morphology and kinematic gait variables in ambulant children with CP?MethodsA retrospective analysis was conducted on data from 121 children with uni- (n = 64, mean age 9.9 (SD 3.4) years) and bi- lateral (n = 57, mean age 10.4 (SD 3.6) years) CP who had undergone 3D gait analysis and biplanar X-rays (EOS® system). The limbs were split as DIP (the more impaired limb of children with bilateral CP), HEMI (the impaired limb of unilateral CP) and REF (the unimpaired limb of unilateral CP). Multi-variable Linear Regressions were performed between 23 kinematic variables, the Gait Deviation Index (GDI) and a model composed of nine 3D bone variables for each limb type.ResultsWhen the whole sample was pooled, 72% of R2 values were poor, 16% were fair, and 12% were moderate. Lower limb bone morphology models explained less than 1% of GDI variability. Correlations between tibial-femoral rotational parameters and hip rotation were mostly poor. Mean foot progression angle was the only kinematic parameter that was fairly to moderately correlated with bone variables in the 3 limb types. A tibial-femoral bone model explained 48% of the variability of mean foot progression angle in the REF limbs, 31% in the HEMI limbs and 25% in the DIP limbs.SignificanceTibial-femoral bone morphology was only weakly related to kinematic gait variables, in contrast with common clinical assumptions. These results suggest that factors other than bone morphology influence gait quality and thus a thorough clinical examination and gait analysis is required prior to making treatment decisions. 相似文献
2.
M. E. Perry Y. Mustafa S. K. Wood M. I. D. Cawley D. C. Dumonde K. A. Brown 《Rheumatology international》1997,17(4):169-174
A morphological examination of synovial tissue from 25 patients with rheumatoid arthritis revealed that binucleated or multinucleated
plasma cells were present in all samples and absent in synovia obtained from 16 control patients. Plasma cells containing
two, three of four nuclei constitutet a mean 3% of the total plasma cell population. They were aways found amongst plasma
cell infiltrates and in close association with small blood vessels. Ultrastructural analysis found no evidence of cellular
membranes separating the individual nuclei in binucleated or multinucleated plasma cells, suggesting that the cells did not
arise from fusion. Some of these plasma cells had a diameter approaching 100 μm, and many were in intimate contact with macrophages.
The demonstration of a few cells with mitotic figures within the infiltrates suggests that the maintenance of plasma cell
numbers in rheumatoid synovium may depend, in part, upon their local proliferation.
Received: 25 August 1997 / Accepted: 2 October 1997 相似文献
3.
4.
CT重建椎弓根轴线投影点定位研究 总被引:7,自引:0,他引:7
目的:建立椎弓根螺钉最佳入钉点,提高椎弓根螺钉内固定术的准确性和安全性。方法:高速螺旋CT共扫描检查40例国人的200个L1~L5脊椎。重建后测量400个椎弓根的入点坐标(x,y),即椎弓根轴线在椎骨后表面的投影点与后正中线的距离(x)及与横突中线的垂直距离(y)。结果:x坐标从L1~L5逐渐增大,男性大于女性(P<0.05);y坐标从L1到L4逐渐下移,在L4与横突中线接近重叠,但L5突然上升,与L2节段水平相当,L1~L5y坐标基本上都在横突中线以上,但每组数据变异较大。就y坐标而言,椎弓根轴线投影点与传统入点比较均有差异。结论:横突中线是椎弓根螺钉置入的重要参照标志,但椎弓根轴线投影点并不在横突中线上,不同个体、节段之间y坐标存在的较大差异是高误置率发生的重要原因。对个体而言,术前常规通过CT测量椎弓根轴线在椎骨后表面的投影点数据对椎弓根螺钉的置入有重要指导意义。 相似文献
5.
强直性脊柱炎股骨近段形态学改变对全髋关节置换术假体选择的意义 总被引:1,自引:1,他引:0
目的分析强直性脊柱炎股骨近段的形态学改变,及其改变对全髋关节置换术假体选择的意义。方法1999年1月~2004年6月,将13例(16髋)强直性脊柱炎患者设为选择组,患者均已出现关节强直,需行全髋关节置换术。另16例(19髋)为对照组,为非强直性脊柱炎患者而拟行全髋关节置换术。两组患者均摄髋关节正侧位X线片,测量Singh指数、髓腔张开指数、皮质形态指数及皮质骨指数,并进行统计学分析。结果选择组Singh指数、髓腔张开指数及皮质形态指数分别为3.81±0.54、2.63±0.41及2.02±0.38,对照组分别为4.63±0.62、3.03±0.27及2.76±0.28,两组比较差异均有统计学意义(P<0.05)。选择组皮质骨指数为1.69±0.69,对照组为2.12±0.24,两组比较差异无统计学意义(P>0.05)。选择组患者髓腔呈烟囱型10例13髋,普通型3例3髋;对照组烟囱型3例3髋,普通型13例16髋。结论强直性脊柱炎的全髋关节置换术应采用骨水泥型人工关节假体,并根据患者髓腔形态使用定制型骨水泥假体,以达到更好的近段固定效果。对于有严重骨质疏松者应按关节翻修术处理。 相似文献
6.
彩色多普勒超声对高度近视眼后巩膜改变相关因素的评价 总被引:2,自引:0,他引:2
目的:探讨高度近视眼后巩膜形态改变与眼轴长度、近视程度及血流动力学变化之间的关系。方法:应用ATL超9型APOOGE-800型彩色多普勒超声诊断仪,探头频率5.0~10.0MHz。对26例正常眼,36例轻中度近视眼,51例高度近视眼后巩膜进行观察。并对26例正常眼,17例轻中度近视眼,26例高度近视眼的眼动脉(OA)、视网膜中央动脉(CRA)、睫状后动脉(PCA)进行检测。结果:轻中度近视组、高度近视组的眼轴长度与近视程度呈正相关性。两者之间的直线回归方程Y=-3510.3 1668.1X,R=0.9432,P<0.0001。后巩膜形态改变与正常对照组比较差异有显著性意义(P<0.001)。高度近视眼组、轻中度近视组与正常对照组比较,OA血流参数差异无显著性意义(P>0.05),而高度近视组的CRA、PCA的收缩期(PSV)、舒张期(EDV)、平均血流速度(AV)均减低,CRA的阻力指数(RI)升高(P<0.05)。轻中度组与对照组比较差异无显著性意义(P>0.05)。结论:视网膜血管、睫状血管系统血供不足与后巩膜形态变化的类型、眼轴长度、近视的程度及血流动力学改变密切相关,是引起高度近视眼病理性眼底改变发生和发展的重要因素。 相似文献
7.
目的观察并探讨骨髓基质细胞向成骨细胞诱导分化过程中细胞超微形态结构的变化及相互联系。方法抽取成年兔髂骨骨髓,分离、培养骨髓基质细胞,1周后分别采用含诱导因子的条件培养液和不含诱导因子的标准培养液继续培养,2周后收集细胞,应用透射电镜观察其超微结构;同时分别将上述两组细胞与煅烧骨体外复合并在原培养液中继续培养,分别于复合1、7、14d取出,用扫描电镜观察细胞表面超微形态。结果透射电镜下见诱导前的骨髓基质细胞浆少,核大,细胞器不发达,处于早期幼稚阶段,而诱导2周后的细胞核小、胞浆多,细胞器丰富,处于较为成熟阶段。扫描电镜下见复合培养2周内诱导前后的骨髓基质细胞均由圆盘形向多角形、条带状相互融合、重叠生长,诱导2周后的骨髓基质细胞间可见大量胶原纤维等基质成分以及钙盐颗粒,而诱导前的细胞始终未见基质分泌及钙盐颗粒。结论成骨诱导后,骨髓基质细胞内细胞器等超微结构极为丰富,细胞表面及细胞间有大量细胞外基质分泌和钙盐沉积。透射电镜和扫描电镜可动态观察骨髓基质细胞向成骨细胞分化过程中细胞超微形态结构的变化。 相似文献
8.
对吸入不同浓度70号汽油小鼠大脑形态学变化的观察结果发现,实验组小鼠脑的髓鞘脱失为其特征性改变,这种病变的数量和大小随吸入汽油浓度的增加愈加明显,病变是一种非炎症性反应,其机理似与汽油的脂溶性有关,脑的髓鞘脱失可能是导致其功能异常,特别是神经传导功能障碍的形态学基础。 相似文献
9.
家兔输卵管结扎术后黄体的形态变化 总被引:2,自引:0,他引:2
将27只雌性家兔随机分为五组,即Pomeroy法扎管组;Uchida法扎管组;结扎子宫动脉组;结扎卵巢动脉组和假手术组。术后4~10周合笼交配。交配后第八天取黄体做光镜和透射电镜观察。结果:Uchida法扎管后黄体的形态正常;Pomeroy法扎管和结扎子宫动脉后黄体的形态有轻微改变;结扎卵巢动脉后黄体的形态有明显改变。研究结果对探讨“扎管后综合征”的发生机制具有一定的意义。 相似文献
10.
Summary In order to learn more about early nerve lesions observed in leprosy, we performed a clinical, electrophysiological and morphological study in seven patients with untreated lepromatous leprosy, palpably enlarged radial cutaneous nerve and preserved sensation in the corresponding territory. The conduction velocity of the cutaneous radial nerve, which was decreased in all patients, did not significantly differ from that of a group of patients with lepromatous leprosy, hypertrophy of the radial cutaneous nerve and sensory loss. In contrast, the sensory action potential was significantly lower in patients with sensory loss, which demonstrates that axon loss is more important than demyelination in producing sensory loss. In all patients nerve enlargement was due to thickening of the epineurium and of the perineurium subsequent to inflammatory infiltrates and proliferation of fibroblasts and perineurial cells. In several fascicles, the inflammatory infiltrates and the infected cells infiltrated endoneurial connective tissue septa and blood vessels.Mycobacteria leprae were abundant in peri neurial cells, fibroblasts, macrophages, Schwarm cells and endothelial cells, and lymphocytic vasculitis present in all cases. The average density of myelinated fibres was 2600 SD 880 fibres/mm2 (control: 7700 fibres/mm2), with marked differences between individual fascicles, versus 420 fibres/mm2 in patients with nerve hypertrophy and sensory loss (range 0–2080 fibres/mm2). Single fibre preparations showed that segmental demyelination pre dominated in two patients, axonal degeneration in one, while inflammatory infiltrates and proliferation of connective tissue adhering to individual fibres were prominent in the others. Both infection of Schwann cells and secretory products released by mononuclear cells involved in the inflammatory process are likely to play a role in the lesions of nerve fibres observed in early stages of lepromatous leprosy.Presented in part at the Second Meeting of the European Neurological Society, Brighton (UK), June 1990 相似文献