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1.
目的分析细棒、PEEK棒固定对寰枢关节稳定性的影响。方法采用6具新鲜成人枕骨(occipital bone,Oc)~颈椎C4节段进行测试,模拟以下手术及固定状态:①完整状态;②损伤状态:枢椎齿状突II型骨折;③坚强固定:寰枢椎均采用普通椎弓根螺钉固定,直径3.5 mm钛棒连接;④PEEK棒:直径3.5 mm的PEEK棒连接;⑤细棒:直径2.0 mm钛棒连接。采用重复测量实验设计,在完整、损伤和不同的固定状态下,通过脊柱试验机对标本分别施加1.5 N·m的前屈/后伸、左/右侧弯和左/右轴向旋转的纯力偶矩。采用Optotrak三维运动测量系统连续采集标本运动,分析寰枢椎之间角度运动范围和中性区。结果采用直径3.5 mm的钛棒,2.0 mm的细棒以及3.5 mm的PEEK棒固定后,在前屈、后伸、侧弯和旋转方向上均显著减小了固定节段的运动范围(P<0.05)。直径3.5 mm和2.0 mm的棒固定后的运动范围,在各个方向上无显著性差异。PEEK棒固定的运动范围仅在侧弯方向上大于坚强固定(P=0.005),其他方向无显著性差异。3种固定方式在屈伸、侧弯和旋转方向上均显著减小了固定节段的中性区(P<0.05)。各种固定方式之间相比较,无显著性差异(P>0.05)。结论在寰枢关节采用直径2.0 mm的细棒固定,与坚强固定的稳定性相当。采用直径3.5 mm的PEEK棒固定,在前屈、后伸、旋转方向上与坚强固定的稳定性相当,在侧弯方向上弱于坚强固定。  相似文献   
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BackgroundAnteriorly-loaded walking is common in many occupations and may increase fall risk. Dynamic gait stability, defined by the Feasible Stability Region (FSR) theory, quantifies the kinematic relationship between the body’s center of mass (COM) and base of support (BOS). FSR-based dynamic gait stability has been used to evaluate the fall risk.Research questionHow does front load carriage affect dynamic gait stability, step length, and trunk angle among young adults during treadmill walking?MethodsIn this between-subject design study, 30 healthy young adults were evenly randomized into three load groups (0%, 10%, or 20% of body weight). Participants carried their assigned load while walking on a treadmill at a speed of 1.2 m/s. Body kinematics were collected during treadmill walking. Dynamic gait stability (the primary variable) was calculated for two gait events: touchdown and liftoff. Step length and trunk angle were measured as secondary variables. One-way analysis of variance was conducted to detect any group-related differences for all variables. Post-hoc analysis with Bonferroni correction was performed when main group differences were found.ResultsNo significant differences but medium to large effect sizes were found between groups for dynamic gait stability at touchdown (p = 0.194, η2 = 0.114) and liftoff (p = 0.122, η2 = 0.139). Trunk angle significantly increased (indicating backward lean) with the front load at touchdown (p < 0.001, η2 = 0.648) and liftoff (p < 0.001, η2 = 0.543). No significant between-group difference was found related to the step length (p = 0.344, η2 = 0.076).SignificanceCarrying a front load during walking significantly alters the trunk orientation and may change the COM-BOS kinematic relationship and, therefore, fall risk. The findings could inform the design of future studies focusing on the impact of anterior load carriage on fall risk during different locomotion.  相似文献   
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陈红亮 《中医学报》2016,(6):910-912
目的:观察理筋通督手法治疗颈性眩晕的临床疗效。方法:将120例颈性眩晕患者随机分成3组,理筋通督组、传统手法组及安慰剂组。理筋通督组采用理筋通督手法;传统手法组采用传统手法;安慰剂组口服维生素C。结果:理筋通督手法可显著减缓患者基底动脉舒张期最低血流速度(P0.05)。理筋通督组有效率为93.67%,传统手法组有效率为67.5%,安慰剂组有效率为17.5%,3组比较差异有统计学意义(P0.05),理筋通督组明显优于其他两组。结论:理筋通督手法治疗颈性眩晕临床疗效显著。  相似文献   
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BackgroundRocker sole (RS) shoes have been linked to impaired postural control. However, which features of RS design affect balance is unclear.Research questionWhich RS design features affect standing balance and gait stability?MethodsThis study utilized an intervention and cross-over design. Twenty healthy young adults (10 males and 10 females) participated in this study. Standing balance and gait stability were measured using a single force platform and three-dimensional motion analysis system, respectively. The experimental conditions included the control shoe and five RS shoes in the combination of apex position (%) and apex angle (degree) for RS50-95, RS60-95, RS70-95, RS60-70, and RS60-110. The main outcome measures were the area surrounding the maximal rectangular amplitude, mean path length, average displacement of the center of pressure along the lateral and anterior/posterior directions, and maximal center of pressure excursion as the standing balance and lateral margin of stability as the gait stability. Statistical analyses were conducted using a two-way split-plot analysis of variance with repeated measures (with RS design as the within-subject factor and sex as the between-subject factor) and the Bonferroni post hoc test (α = .05).ResultsRegarding the mean path length, RS60-70 was significantly longer than the control shoe, and it showed a significantly increased lateral margin of stability. Thus, RS60-70 was shown to affect standing balance, limit of stability, and gait stability of the frontal plane during gait.SignificanceThese results suggest that the apex angle of the RS design feature affects standing balance and gait stability, and RS60-70 is detrimental to stability. Therefore, when RS with a small apex angle is prescribed, it is necessary to consider the patient’s balance ability.  相似文献   
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《Foot and Ankle Surgery》2020,26(2):193-197
BackgroundThe aim of this study was to compare the radiographic and functional results between fixation and non-fixation in the Cotton osteotomy for the treatment of adult acquired flatfoot.MethodsA retrospective, case-controlled study of consecutive stage IIB posterior tibial tendon dysfunction (PTTD) patients treated with the same bony reconstructive surgery including cotton osteotomy between 2013 and 2017. Meary’s angle, the medial arch sag angle (MASA), and medial cuneiform cobb angle (MCCA) were evaluated pre-operation, at first weight bearing after surgery, and 12 months post operation.ResultsForty feet were included in the study. The cotton osteotomy utilized screw fixation (n = 20) or non-fixation technique (n = 20). No significant differences between groups were found in pre-operative and follow-up radiographic parameters, union rate, and functional results.ConclusionThe non-fixation with press fit technique is a reliable procedure for Cotton osteotomy and as effective as screw fixation.Level of evidenceLevel III, case control study  相似文献   
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《中国现代医生》2020,58(4):182-184+188
目的 探讨脊柱后路内固定术后硬膜外血肿的预防与护理体会。方法 遵照回顾性分析法选择我院2013年2 月~2018 年2 月纳入的60 例脊柱后路内固定术患者,依照不同理疗方式进行分组。其中30 例给予常规药物治疗作为对照组,另30 例除了常规治疗之外实施综合护理作为研究组,记录两组硬膜外血肿、腰椎术后血肿及颈椎术后血肿发生率,分别在干预前后进行生活质量评分(QOL)调查,出院时发放满意度调查问卷表,对比两组干预结果。结果 研究组血肿发生率为6.67%,明显低于对照组的20.00%(P<0.05)。干预前两组的食欲、精神、睡眠、疼痛及日常生活评分相比差异无统计学意义(P>0.05),干预后研究组的各项评分均高于对照组(P<0.05)。研究组对干预效果的满意度为90.00%,明显高于对照组的76.67%(P<0.05)。结论 护理干预运用于脊柱后路内固定中效果显著,能够有效减少硬膜外血肿的发生率,提升生活质量,促进病情稳定,患者满意度较高,可维持良好医患关系。  相似文献   
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Background: Self sampled HPV testing is a cervical cancer screening method . However, cytology in self-sampled specimen cannot be used as a triage test.  Therefore, other methods for triage should be considered. CyclinA1 (CCNA1) promoter methylation has strong association with cervical precancerous and cancerous lesion. The objective of this study was to compare the diagnostic value of CCNA1 and self-sampled specimen for detecting high-grade cervical intraepithelial lesions or worse (CIN2+). Materials and Methods: A cross sectional study was conducted. Women with abnormal cytology or positive for high risk HPV (hrHPV) indicated for colposcopic examination were enrolled.  Self-collected sampling for hrHPV DNA (SS-HPV) and CCNA1 were performed. hrHPV DNA testing was done by Cobas 4800 method. CCNA1 promoter methylation was detected by CCNA1 duplex methylation specific PCR. Histopathologic result as CIN2+ obtaining from colposcopic directed biopsy or excisional procedure  was considered as positive a gold standard. The results of hrHPV and CCNA1 were reported as positive or negative. Sensitivity specificity, positive predictive value, and negative predictive value of SS-HPV and CCNA1 were calculated by comparing the results with the gold standard. Results: Two hundreds and eighty women were recruited. High-grade cervical lesions and cervical cancer (CIN2+) were diagnosed in 21.8% (61 cases) of the patients. The most common type of hrHPV was non 16, 18 subtype, followed by HPV16 and 18. CCNA1 was positive in 13 patients out of whom, twelve were CIN2+. Sensitivity of CCNA1 was 19.7 % and its  specificity and accuracy were 99.5% and 82.14%, respectively.  The sensitivity of SS-HPV was 70.5%, and its  specificity and accuracy were 39.2% and 43.3%, respectively. Conclusion:  Due to high specificity and positive predictive value of CCNA1, it can be used as alarming sign of having high-grade cervical intraepithelial lesions, especially in patient who has positive hrHPV DNA test based on self-collected sampling.  相似文献   
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