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51.

Objective

The aim of the study was to assessment the impact of hip osteoarthritis on postural stability.

Methods

One hundred and twenty-five randomly selected women 20–85 years old (mean age of 49 ± 24.4 years) were assigned to three groups based on age, health status and activity level. Group 1 (cases) – elderly women with diagnosed hip osteoarthritis, group 2 (control) - women without hip osteoarthritis, and group 3 (control) - healthy young women. Assessment of postural stability were measured using a WIN-POD Pel 38 electronic podometer. Statistica 10 software was used to perform t-test resulting in significance level of p < 0.05.

Results

Significant differences in pedobarographic balance measurements were observed between the study groups with eyes opened or closed (deviation length eyes open: group 1–3 and 2–3 p < 0.0001; eyes closed group 1–2 p = 0.19; 1–3 and 2–3 p < 0.0001; deviation area eyes open: group 1-3 and 2–3 p < 0.0001; eyes closed group 1–3 and 2–3 p < 0.0001; deviation velocity eyes open: group1-3 and 2–3 p < 0.0001; eyes closed group 1–2 p < 0.010, 1–3 and 2–3 p < 0.0001). The poorest postural stability was observed in patients with hip osteoarthritis (deviation length eyes open vs eyes closed 180.8/201.7 p = 0.028, deviation area 128.7/145.7 p = 0.771, deviation velocity 5.1/6.1 p < 0.0001), and the best postural stability was observed in young women (deviation length 111.3/137.5 p < 0.0001, deviation area 57/76.9 p = 0.003, deviation velocity 3.4/4.2 p < 0.0001).

Conclusion

(1) Osteoarthritic degeneration of the hip joint results in a significant disturbance in proprioception. This finding was reflected by the inferior stability parameters collected from subjects with hip osteoarthritis when asked to stand with their eyes closed. These finding were not observed in the other groups. (2) The disorder of the body stability of people with osteoarthritis may be a relative indication for the implantation of hip arthroplasty.  相似文献   
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The ligament of the head of femur (LHF) has gained clinical attention recently and is reported to contribute to hip stability. This study explores its morphology and morphometry, information that may help inform surgical decision making. Gross anatomical dissections were undertaken on 229 embalmed hips from European (n = 105) and Thai (n = 124) adult cadavers to examine LHF anatomy. Ligament morphometry was statistically compared at different sites, between sexes and sides. The origin of ligamental arteries and absence of the ligament were documented. The LHF was pyramidal or quadrangular in shape. Sub‐synovial fibrous bands originated from the transverse acetabular ligament, edges of the acetabular notch, and acetabular floor; less frequently from the hip joint capsule. Distally, the ligament flattened and converged onto the fovea capitis. The ligament was 22.3 ± 4.4 mm long and was significantly wider (P = 0.001) and thicker (P = 0.0003) at the fovea, compared to its mid‐zone. Branches of the obturator artery entered the acetabular foramen inferomedially and penetrated the middle third of the LHF. Blood vessels ran within the LHF and appeared to enter the fovea. The ligament was absent in 2.8% of Thai hips and there were no significant sex or side differences in ligament dimensions. The morphology of the LHF is complex. While individual variation was apparent, blood vessels were seen in the distal ligament. Precise information on LHF morphometry and attachment sites will help inform appropriate graft dimensions and choice of fixation sites necessary for ligament reconstruction. Clin. Anat., 2018. © 2018 Wiley Periodicals, Inc. Clin. Anat., 2018. © 2018 Wiley Periodicals, Inc.  相似文献   
54.
《Clinical neurophysiology》2019,130(1):128-137
ObjectiveHigh frequency oscillations (HFO) between 80–500 Hz are markers of epileptic areas in intracranial and maybe also scalp EEG. We investigate simultaneous recordings of scalp and intracranial EEG and hypothesize that scalp HFOs provide important additional clinical information in the presurgical setting.MethodsSpikes and HFOs were visually identified in all intracranial scalp EEG channels. Analysis of correlation of event location between intracranial and scalp EEG as well as relationship between events and the SOZ and zone of surgical removal was performed.Results24 patients could be included, 23 showed spikes and 19 HFOs on scalp recordings. In 15/19 patients highest scalp HFO rate was located over the implantation side, with 13 patients having the highest scalp and intracranial HFO rate over the same region. 17 patients underwent surgery, 7 became seizure free. Patients with poor post-operative outcome showed significantly more regions with HFO than those with seizure free outcome.ConclusionsScalp HFOs are mostly located over the SOZ. Widespread scalp HFOs are indicative of a larger epileptic network and associated with poor postsurgical outcome.SignificanceAnalysis of scalp HFO add clinically important information about the extent of epileptic areas during presurgical simultaneous scalp and intracranial EEG recordings.  相似文献   
55.
《The Journal of arthroplasty》2019,34(8):1711-1717
BackgroundThe declining popularity of cemented acetabular components is incongruous, given the published results of prostheses implanted using contemporary techniques. The outcome of arthroplasty has previously been demonstrated to correlate with surgeon experience and volume of practice. We aim to explore if surgeon volume alters outcomes of cemented acetabular components based on survivorship data from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR).MethodsAn observational study was undertaken using a cohort of 22,956 patients with a primary diagnosis of osteoarthritis in the period 2003-2016 in whom cemented acetabular components were implanted. The cohort was stratified by age (greater than or less than 65 years) and annualized surgical volume of ≤10, >10-≤25, and >25 cases.ResultsStratified by age and volume, there was a protective benefit against revision conveyed at volume thresholds of 10 cases per annum and 25 cases per annum for patients ≥65 years of age and <65 years of age, respectively.ConclusionCemented total hip arthroplasty has excellent survivorship out to 15 years based on AOANJRR data. This survivorship is further improved if surgeons perform a higher volume of cases, with >25 cases conferring the greatest benefit. The AOANJRR data set is used to define best practice; surgeons who choose to utilize cemented acetabular fixation should be encouraged to perform this technique in adequate volumes to minimize revision risk and ensure the preservation of this important surgical skill set.  相似文献   
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Recently, we developed a high-frame-rate echocardiographic imaging system capable of acquiring images at rates up to 2500 per second. High imaging rates were used to quantify longitudinal strain parameters in patients with echocardiographically normal function. These data can serve as a baseline for comparing strain parameters in disease states. The derived timing data also reveal the propagation of mechanical events in the left ventricle throughout the cardiac cycle. High-frame-rate echocardiographic images were acquired from 17 patients in the apical four-chamber view using Duke University's phased array ultrasound system, T5. B-Mode images were acquired at 500–1000 images per second by employing 16:1 or 32:1 parallel processing in receive, a scan depth ≤14 cm and an 80° field of view with a 3.5-MegaHertZ (MHz), 96-element linear array. The images were analyzed using a speckle tracking algorithm tailored for high-frame-rate echocardiographic images developed at Aalborg and Duke University. Four specific mechanical events were defined using strain curves from six regions along the myocardial contour of the left ventricle. The strain curves measure the local deformation events of the myocardium and are independent of the overall cardiac motion. We observed statistically significant differences in the temporal sequence among different myocardial segments for the first mechanical event described, myocardial tissue shortening onset (p < 0.01). We found that the spatial origin of tissue shortening was located near the middle of the interventricular septum in patients with echocardiographically normal function. The quantitative parameters defined here, based on high-speed strain measurements in patients with echocardiographically normal function, can serve as a means of assessing degree of contractile abnormality in the myocardium and enable the identification of contraction propagation. The relative timing pattern among specific events with respect to the Q wave may become an important new metric in assessing cardiac function and may, in turn, improve diagnosis and prognosis.  相似文献   
59.
目的 探讨细胞黏附分子CD99在人髓母细胞瘤组织中的表达特点及其临床意义。方法 采用免疫组化法检测107例髓母细胞瘤及15例瘤旁正常脑组织标本中CD99的表达。所有病人均随访至死亡或截止至2013年12月,随访时间为12~80个月,利用Kaplan-Meier生存曲线进行生存分析。结果 髓母细胞瘤CD99阳性表达率(57.94%,62/107)明显高于瘤周正常脑组织(0%,0/15;P<0.05)。CD99的表达水平与病人性别、年龄、肿瘤的病理组织学分型和分子亚型均无明显相关性(P>0.05)。CD99的高表达与髓母细胞瘤病人的预后呈显著负相关(P<0.05)。结论 CD99高表达与髓母细胞瘤预后显著相关,可作为预后判断的指标及治疗髓母细胞瘤潜在的新靶点。  相似文献   
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