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81.

Objective

Biomechanical comparison between locked plating and retrograde nailing of supracondylar femur fractures with simulated postoperative weight-bearing.

Methods

The Locking Condylar Plate (LCP) and Retrograde/Antegrade EX Femoral Nail (RAFN) were tested using 10 paired elderly cadaveric femurs, divided into Normal and Low Bone Mineral Density (BMD) groups, with a simulated AO/OTA type 33-A3 supracondylar femur fracture. Each specimen was subjected to 200,000 loading cycles in an attempt to simulate six weeks of postoperative recovery with full weight-bearing for an average individual. The construct's subsidence due to cyclic loading, and axial stiffness before and after the cyclic loading were measured and their correlation with BMD was studied. The two implants were compared in a paired study within each BMD group.

Results

LCP constructs showed higher axial stiffness compared to RAFN for both Normal and Low BMD groups (80% and 57%, respectively). After cyclic loading, axial stiffness of both constructs decreased by 20% and RAFN constructs resulted in twice as much subsidence (1.9 ± 0.6 mm). Two RAFN constructs with Low BMD failed after a few cycles whereas the matched pairs fixed with LCP failed after 70,000 cycles.

Conclusions

The RAFN constructs experienced greater subsidence and reduced axial stiffness compared to the LCP constructs. In Low BMD specimens, the RAFN constructs had a higher risk of failure.  相似文献   
82.
目的探讨婴儿期白内障摘除手术后患儿眼轴长度、角膜屈光力、屈光度数变化情况及其发展规律。方法回顾性队列研究。选取2015年1月1日至2018年12月31日在温州医科大学附属眼视光医院杭州院区103例因先天性白内障婴儿期接受白内障摘除手术患儿的病历资料,男性61例,女性42例,行手术时月龄为(3.95±1.94)个月。双眼白内障患儿均双眼接受白内障摘除手术,选取左眼进行分析。入选患儿至少随访1年,患儿按白内障摘除手术时月龄分为<4月龄组和4~12月龄组,比较患儿白内障摘除手术前及手术后1年的眼轴长度、角膜屈光力、检影验光的等效球镜度数以及变化量,采用独立样本t检验、单因素方差分析和简单线性回归法进行统计学分析。结果双眼白内障患儿71例,<4月龄组33例,4~12月龄组38例;单眼白内障患儿32例,<4月龄组17例,4~12月龄组15例。<4月龄组双眼患儿术后1年眼轴长度变化量为(2.46±1.33)mm,大于4~12月龄组的(1.52±1.00)mm,差异有统计学意义(t=3.21;P<0.01)。相同手术月龄分组中,双眼患儿患眼、单眼患儿患眼及对侧眼,三者间术后1年眼轴长度变化量差异均无统计学意义(均P>0.05)。术后1年,双眼患儿患眼、单眼患儿患眼及对侧眼眼轴长度均与实际月龄的对数高度正相关(r=0.68,0.52,0.73;均P<0.01)。角膜屈光力随年龄增大总体呈减少趋势,<4月龄组双眼患儿术后1年角膜屈光力变化量为(1.43±2.87)D,大于4~12月龄组的(0.68±2.10)D,但差异无统计学意义(P>0.05)。<4月龄组双眼患儿术后1年屈光度数变化量为(2.02±2.60)D,大于4~12月龄组的(0.69±1.89)D,差异有统计学意义(t=2.15;P<0.05)。单眼患儿患眼4~12月龄组术后1年屈光度数变化量为(2.05±0.95)D,大于双眼患儿4~12月龄组的(0.69±1.89)D,差异有统计学意义(t=2.49;P<0.05)。术后1年,双眼及单眼患儿患眼屈光度数均与实际月龄成高度负相关(r=-0.51,-0.54;均P<0.01)。结论婴儿期白内障摘除手术后1年,患儿眼轴长度增长,角膜屈光力降低,屈光度数降低,且患儿手术年龄越小,眼轴长度、角膜屈光力、近视漂移变化量越大。  相似文献   
83.
目的分析中国18家医院的14万例年龄相关性白内障患者角膜前表面散光的分布特征。方法回顾性系列病例研究。连续性收集2015年7月至2018年10月于中国18家爱尔眼科医院就诊的40岁以上年龄相关性白内障患者143889例(143889只右眼)的眼部生物学参数资料。角膜前表面散光度数和轴向、前房深度、角膜屈光力、眼轴长度等眼球参数采用IOLMaster 500测量,获取3次测量结果的平均值。各医院将资料整理分析后提交给武汉爱尔眼科医院进行总体分析。非正态分布数据以M(P25~P75)表示;采用Mann-Whitney检验、Kruskal-Wallis检验、χ2检验等分析角膜前表面散光度数和轴向在不同性别、年龄、前房深度、角膜屈光力、眼轴长度中的分布差异。结果143889例患者中女性84319例,男性59570例;年龄为72(65~78)岁;角膜散光度数为0.84(0.51~1.33)D,散光度数≥0.75 D者80895例(56.22%),散光度数≥1.00 D者57304例(39.83%)。女性角膜散光度数为0.87(0.53~1.37)D,男性为0.82(0.50~1.29)D(U=-14.891);女性顺规散光比例为33.26%(28046/84319),逆规散光比例为49.08%(41385/84319);男性顺规散光比例为34.26%(20408/59570),逆规散光比例为46.91%(27945/59570)(χ2=70.913),差异均有统计学意义(均P<0.05)。随年龄增加,角膜散光度数先由0.94(0.57~1.48)D减少至0.75(0.46~1.18)D,后又增大至1.19(0.74~1.79)D,差异有统计学意义(H=1263.438,P<0.05),变化的转折在61~70岁。随着年龄的增大,顺规散光比例减小[由77.50%(396/511)减少至12.50%(3/24)],逆规散光比例增大[由11.15%(57/511)增大至79.07%(34/43)],斜向散光比例变化不大[17.02%(16/94)至19.92%(245/1230)],分布差异有统计学意义(χ2=10174.496,P<0.05)。前房越浅,角膜散光度数越大,由0.82(0.51~1.31)D增大至1.05(0.61~1.56)D;逆规散光比例越大,由47.32%(60207/127227)增大至51.69%(184/356),差异均有统计学意义(H=409.961,χ2=120.995;均P<0.05)。平均角膜屈光力越大,角膜散光度数越大,由0.80(0.49~1.33)D增大至0.95(0.58~1.53)D;逆规散光比例越小,由52.84%(4963/9392)减小至39.97%(9023/22577),差异均有统计学意义(H=808.562,χ2=752.147;均P<0.05)。不同眼轴长度相比,当眼轴长度>25.00 mm时,角膜散光度数最大,为1.04(0.62~1.65)D;逆规散光比例最大,为49.00%(10964/22376),差异均有统计学意义(H=2071.198,χ2=131.130;均P<0.05)。结论年龄相关性白内障患者角膜前表面散光轴向以逆规散光为主。随着年龄的增大,角膜散光度数有先减小后增加的趋势。65岁为顺规散光向逆规散光变化的转折点。前房越浅,角膜前表面散光度数以及逆规散光比例越大。当眼轴长度>25.00 mm时,角膜前表面散光度数和逆规散光比例最大。  相似文献   
84.

Background

Gastro-oesophageal reflux symptoms are usually reported by patients with obesity and metabolic syndrome. Aim of this study was to assess the prevalence and clinical characteristics of gastro-oesophageal reflux symptoms in subjects with non-alcoholic fatty liver disease.

Methods

Cross-sectional, case–control study of 185 consecutive patients with non-alcoholic fatty liver disease and an age- and sex-matched control group of 112 healthy volunteers. Participants were interviewed with the aid of a previously validated questionnaire to assess lifestyle and reflux symptoms in the 3 months preceding enrolment. Odds ratios were determined before and after adjustment for body mass index, increased waist circumference, physical activity, metabolic syndrome and proton pump inhibitors and/or antiacid medication.

Results

The prevalence of heartburn and/or regurgitation and of at least one of gastro-oesophageal reflux symptoms was significantly higher in the non-alcoholic fatty liver disease group. Non-alcoholic fatty liver disease subjects were associated to higher prevalence of heartburn (adjusted odds ratios: 2.17, 95% confidence intervals: 1.16–4.04), regurgitation (adjusted odds ratios: 2.61, 95% confidence intervals: 1.24–5.48) and belching (adjusted odds ratios: 2.01, 95% confidence intervals: 1.12–3.59) and had higher prevalence of at least one GER symptom (adjusted odds ratios: 3.34, 95% confidence intervals: 1.76–6.36).

Conclusion

Non-alcoholic fatty liver disease is associated with a higher prevalence of gastro-oesophageal reflux symptoms.  相似文献   
85.
目的 比较综合性医院眼科与眼科专科医院高度近视白内障患者术后视力,分析高度近视白内障患者术后视力的影响因素。方法 选择在复旦大学附属华东医院及复旦大学附属眼耳鼻喉科医院进行超声乳化白内障摘除合并人工晶状体植入手术的眼轴长度≥26 mm的高度近视患者77例(77眼)。术前记录患者眼部生物学特征及眼底相干光层析成像(OCT)情况,并按医院不同分为2组,比较2组术后视力,并分析术后最佳矫正视力(BCVA)与术前眼部特征的相关性。结果 眼耳鼻喉科医院收治的高度近视白内障患者更年轻、眼轴长度更长、合并的黄斑疾病更多(P<0.05)。所有患者术后视力均有提高(P<0.001),2家医院平均术后BCVA差异无统计学意义(P=0.805)。单因素分析显示,高度近视白内障患者术后BCVA(logMAR)与眼轴长度、光感受器内外节连接(IS/OS)不连续及合并黄斑牵引性疾病呈正相关,与黄斑中心凹视网膜厚度呈负相关(P<0.05)。逐步向后多元线性回归分析显示高度近视白内障术后BCVA的独立影响因素为眼轴长度、IS/OS连续性及术前BCVA。结论 超声乳化白内障摘除合并人工晶状体植入手术治疗高度近视白内障安全有效,其疗效受眼轴长度、IS/OS连续性及术前BCVA影响。  相似文献   
86.

Purpose

To investigate the long-term impacts of different posterior operations on curvature, neurological improvement and axial symptoms for multilevel cervical degenerative myelopathy (CDM), and to study the relationship among loss of cervical lordosis, recovery rate and axial symptom severity.

Methods

We retrospectively reviewed 98 patients with multilevel CDM who had undergone laminoplasty (Group LP, 36 patients), laminectomy (Group LC, 30 patients), or laminectomy with lateral mass screw fixation (Group LCS, 32 patients) between January 2000 and January 2005. Loss of curvature index (CI) was measured according to the preoperative and final follow-up radiographic parameters. The recovery rate was calculated based on the Japanese Orthopedic Association (JOA) score. Axial symptom severity was quantified by Neck Disability Index (NDI).

Results

Analysis of final follow-up data showed significant differences among the three groups regarding loss of CI (F = 41.46, P < 0.001) between preoperative and final follow-up JOA scores (P < 0.001), final follow-up JOA score (F = 7.81, P < 0.001), recovery rate (F = 12.98, P < 0.001) and axial symptom severity (χ2 = 18.04, P < 0.001). Loss of CI showed negative association with neurological recovery (r = −0.555, P < 0.001) and positive correlation with axial symptom severity (r = 0.696, P < 0.001).

Conclusions

Excellent neurological improvement was obtained by LP and LCS for patients with multilevel CDM, while loss of CI in groups LP and LC caused a high incidence of axial symptoms. Loss of CI was correlated with poor neurological recovery and axial symptom severity. Lateral mass screw fixation can effectively prevent loss of postoperative cervical curvature and reduce incidence of axial symptoms.  相似文献   
87.
目的:总结保留颈半棘肌肌止、C3椎板切除、C4~C7“锚定”单开门椎管扩大成形术治疗多节段脊髓型颈椎病的临床效果.方法:2009年1月~2011年10月,共对74例多节段脊髓型颈椎病患者采用保留颈半棘肌肌止、C3椎板切除、“锚定法”固定悬吊C4~C7椎板的单开门椎管扩大成形术治疗,其中57例患者获得随访,男31例,女26例,年龄50~71岁,平均63岁.术前JOA评分4~11分,平均8.5±2.0分,颈椎活动度23°~49°,平均37.4°±10.3°,颈椎曲度指数6.0%~22.0%,平均(13.9±7.4)%.观察患者术中和术后并发症发生情况;术后6个月复查颈椎X线片,测量颈椎曲度指数和颈椎活动度,观察颈椎曲度指数和颈椎活动度变化情况;末次随访时对患者神经功能进行JOA评分,计算神经功能改善率 结果:手术均顺利完成,手术时间50~110min,平均70min.术中出血150~600ml,平均230ml.术中无脊髓损伤、脑脊液漏等并发症发生.术后早期41例患者有颈痛,给予消炎镇痛治疗,术后3周内疼痛消失或明显缓解2例出现切口感染,经抗感染治疗并再次清创后切口延时愈合.9例有明显轴性症状,发生率为15.8%;6例出现C5神经根麻痹,给予甲基强的松龙、营养神经药物等治疗后症状明显缓解.随访6~32个月,平均13个月,术后6个月颈椎曲度指数为4.2%~21.1%,平均(11.3±8.1)%,较术前丢失(2.9±2.4)%;颈椎活动度为18°~46°,平均28.2°±10.8°,平均丢失8.2°±5.1°.患者神经功能均不同程度得到改善,末次随访时JOA评分为10~17分,平均13.8±2.3分,较术前明显提高(P<0.05),神经功能改善率为29.0%~77.3%,平均(57.0±19.7)%.末次随访均未发现“再关门”现象.结论:保留颈半棘肌肌止、C3椎板切除、“锚定法”固定悬吊C4~C7椎板的单开门椎管扩大成形术可明显改善多节段脊髓型颈椎病患者的神经功能,手术操作简单,临床疗效满意.  相似文献   
88.
AMS量表在上海市社区人群中的适用性研究   总被引:1,自引:0,他引:1  
目的:评价在上海社区人群中应用AMS量表(the aging males'symptoms scale)的信度和效度。方法:以上海市某社区40岁及以上的973例中老年男性为研究对象,采用AMS量表进行调查,计算分半信度系数、Cronbach'sα系数考察量表内在一致性;通过验证性因子分析考察结构效度,t检验、方差分析和相关分析考察区分效度、校标效度和内容效度。结果:AMS量表及各领域的分半信度系数均大于0.78(P<0.01),Cronbach'sα均大于0.82(P<0.01);验证性因子分析结果表明AMS量表可分为3个领域,各条目与其所属领域的相关系数均大于0.49(P<0.01);血清总睾酮水平为校标时的Pearson相关系数为-0.04(P>0.05)。除心理领域得分在不同年龄组间差别无统计学意义外,不同年龄组、有无慢性病组间AMS量表及各领域得分均存在统计学差异。结论:AMS量表应用于上海社区人群时具有较好的信度和效度,是一份较好的老年男性症状评分量表。但其作为迟发性性腺功能减退症(LOH)的筛选工具仍需深入评估。  相似文献   
89.
The main objective of this study was to compare symptom load and lifetime treatment experiences between psychotic patients with substance abuse problems and psychotic patients without substance abuse problems. This is a cross-sectional study of 48 patients (26 inpatients and 22 outpatients) in a clinic for early intervention in psychosis. Patients’ were grouped into two categories based on whether they had a substance abuse problem or not. Twenty-one (43.8%) had a substance abuse problem and 27 (56.2%) had not. We used the Positive and Negative Symptom Scale (PANSS) scale to measure symptoms and several scales to measure substance abuse. Parametric tests (independent t-tests) were used to compare continuous variables, and chi-square tests were used to compare frequencies. Positive symptoms, negative symptoms, general psychopathology symptoms and the total score of psychotic symptoms did not differ significantly between the groups with psychosis alone and psychosis with substance abuse. The delusion subscore was significantly higher in the group with psychosis alone (t=?2.3, df=41, P<0.05), and the anxiety subscore was significantly higher in the group with psychosis with substance abuse (t=?2.3, df=41, P<0.05). There were no significant differences in the subscores for negative symptoms. The absence of differences in psychotic symptoms between the two groups with psychosis does not imply a strong relationship between psychotic symptoms and substance abuse. These results do not support the self-medication hypothesis. The higher rates of institutionalization among substance abusers may be explained by mechanisms other than exacerbations of psychotic symptoms, as there are few differences in symptoms among abusers and non-abusers.  相似文献   
90.
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