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91.
目的利用核磁共振成像和三维图像后处理技术,在上臂被动抬高过程中对肩带的盂-肱结构进行基本运动分析.方法选用20个志愿者,利用开放核磁共振系统对上臂5个不同外展位置(30°、60°、90°、120°、150°)进行扫描.经过分层扫描采集数据后,实施三维重建,确定肱骨和关节盂平面的轴,并计算它们相对于参考平面之间的运动.结果获得了上臂被动抬高过程中盂-肱结构相对参考平面运动的特殊三维运动数据.结论利用核磁共振成像和三维图像后处理技术可以揭示在上臂被动抬高过程中盂-肱关节相对参考系运动的特殊三维运动模式;所用技术和获得的数据可用于进一步研究患者异常的肩关节运动病理性改变.  相似文献   
92.

Objective

To perform risk analysis of tracheal injuries caused by endotracheal intubation (ETI) and to estimate the financial impact of these sequelae.

Study Design

Cost analysis using a national database.

Settings

The Agency for Healthcare Research and Quality (AHRQ) 2006 National Inpatient Sample.

Subjects and Methods

We identified clinical manifestations and treatments of complications associated with endotracheal tubes and codified them into International Classification of Disease-ninth revision diagnosis and procedure codes, intentionally excluding alternative etiologies of tracheal injury. Using the AHRQ 2006 National Inpatient Sample, we then compared patients with tracheal injury coded during the medical or surgical stay for length of stay (LOS) and mean hospital cost with diagnosis-related group (DRG)-matched controls; we also examined readmissions treating tracheal injury.

Results

Tracheal injury presents as tracheal stenosis, tracheomalacia, tracheoesophageal fistula, laryngotracheal ulceration, and vocal cord paralysis. A total of 3232 discharge records met criteria for tracheal injury from ETI within the index hospital stay. Average LOS for patients with tracheal injury (6.3 days; 95% confidence interval [CI] 6.0-6.3) exceeded LOS in the uncomplicated sample (5.2 days; CI 5.1-5.3) by 1.1 days. The average hospital cost was $1888 higher with tracheal injury ($10,375 [CI $9762-$10,988] vs $8487 [CI $8266-$8669]). LOS for procedures treating prior tracheal injury averaged 4.7 days and cost an average of $11,025 per discharge.

Conclusion

Tracheal injury from ETI is associated with a significant increase in healthcare costs that accrue both during the index admission and during subsequent hospitalizations required to treat the injury.  相似文献   
93.
Axial vertebral rotation (AVR) of 14 normal and 14 scoliotic vertebrae from magnetic resonance (MR) images was determined by three observers using four manual methods and a computerized method, which were based on the evaluation of vertebral symmetry in two dimensions (2D) and in three dimensions (3D). The method of Aaro and Dahlborn proved to be the manual method with the highest intra-observer (1.7° SD) and inter-observer (1.2° SD) reliabilities, and was also most in agreement with the computerized method (1.3° SD, 1.0° MAD). The computerized method yielded higher intra-observer (1.3° SD) and inter-observer (1.4° SD) reliabilities than the manual methods, indicating it to be an efficient alternative for repeatable and reliable AVR measurements.  相似文献   
94.
The literature reports inconsistent findings regarding the association between low back pain (LBP) and trunk muscle function, in both adults and children. The strength of the relationship appears to be influenced by how LBP is qualified and the means by which muscle function is measured. The aim of this study was to examine the association between isoinertial trunk muscle performance and consequential (non-trivial) low back pain (LBP) in male adolescents. Healthy male adolescents underwent anthropometric measurements, clinical evaluation, and tests of trunk range of motion (ROM), maximum isometric strength (STRENGTH) and peak movement velocity (VEL), using an isoinertial device. They provided information about their regular sporting activities, history and family history of LBP. Predictors of “relevant/consequential LBP” were examined using multivariable logistic regression. LBP status was reassessed after 2 years and the change from baseline was categorised. At baseline, 33/95 (35%) subjects reported having experienced consequential LBP. BMI, a family history of LBP, and regularly playing sport were each significantly associated with a history of consequential LBP (p < 0.05). 85/95 (89%) boys participated in the follow-up: 51 (60%) reported no LBP at either baseline or follow-up (never LBP); 5 (6%) no LBP at baseline, but LBP at follow-up (new LBP); 19 (22%) LBP at baseline, but none at follow-up; and 10 (12%) LBP at both time-points (recurrent/persistent LBP). The only distinguishing features of group membership in these small groups were: fewer sport-active in the “never LBP” group); worse trunk mobility, in the “persistent LBP” group, lower baseline sagittal ROM in the “never LBP” and “new LBP” (p < 0.05). Regular involvement in sport was a consistent predictor of LBP. Isoinertial trunk performance was not associated with LBP in adolescents.  相似文献   
95.
Summary Bone loss was confirmed after 90 days in 50 6-month-old male Sprague Dawley rats that were sham-operated or orchidectomized (ORX). In this study, we have shown that dried plum (DP) has potent effects on bone in terms of bone mass, microarchitecture, and strength in osteopenic male rats. Although these changes may be mediated through the suppression of bone resorption, the fact that the restoration in some of the bone structural and biomechanical parameter shares some similarities with parathyroid hormone (PTH) should not be overlooked. Further investigation is needed on a mechanistic level to clarify the influence of DP on bone metabolism. Introduction This study was designed to investigate the extent to which DP reverses bone loss in osteopenic ORX rats and to compare its effects to PTH. Materials and methods Fifty, 6-month-old male Sprague Dawley rats were sham-operated or ORX, and bone loss was confirmed after 90 days. The ORX groups were assigned to control (AIN-93M) diet, 25% DP diet, or PTH (80 μg/kg) for 90 days. Results DP induced an 11% increase in vertebral and femoral BMD compared to ORX-controls. BMD in the PTH-treated group was increased by 20.7% (vertebra) and 17.9% (femur). Vertebral trabecular bone volume (BV/TV) and number were increased by DP and trabecular separation was decreased compared to controls, which were similar to PTH. Alterations in trabecular bone of the femur were similar to those in the vertebra, but DP did not restore BV/TV to the same extent. Cortical thickness was improved by DP and further enhanced by PTH. DP tended to decrease urinary deoxypyridinoline and calcium, but did not alter alkaline phosphatase or osteocalcin. Conclusion We conclude that though the degree of improvement was not equivalent to PTH with regard to all parameters, DP reverses bone loss due to ORX and the mechanisms should be further investigated.  相似文献   
96.
This study examines cell death and proliferation in the white matter after neonatal stroke. In postnatal day 7 injured rat, there was a marked reduction in myelin basic protein (MBP) immunostaining mainly corresponding to numerous pyknotic immature oligodendrocytes and TUNEL-positive astrocytes in the ipsilateral external capsule. In contrast, a substantial restoration of MBP, as indicated by the MBP ratio of left-to-right, occurred in the cingulum at 48 (1.27 +/- 0.12) and 72 (1.30 +/- 0.18, P < 0.05) h of recovery as compared to age-matched controls (1.03 +/- 0.14). Ki-67 immunostaining revealed a first peak of newly generated cells in the dorsolateral hippocampal subventricular zone and cingulum at 72 h after reperfusion. Double immunofluorescence revealed that most of the Ki-67-positive cells were astrocytes at 48 h and NG2 pre-oligodendrocytes at 72 h of recovery. Microglia infiltration occurs over several days in the cingulum, and a huge quantity of macrophages reached the subcortical white matter where they engulfed immature oligodendrocytes. The overall results suggest that the persistent activation of microglia involves a chronic component of immunoinflammation, which overwhelms repair processes and contributes to cystic growth in the developing brain.  相似文献   
97.
目的 对比观察自体外周血干细胞(APBSC)/脱钙骨(DB)复合移植与自体外红骨髓(ARBM)/DB复合移植治疗骨缺损的疗效。方法 36只家兔双侧桡骨造成1cm骨缺损,随机分为DB组、ARBM/DM级和APBSC/DB组,每组12只,分别进行X线片、生物力学和组织学检查,然后作对比分析。结果 术后第2、4、8、14周,APBSC/DB组和ARBM/DB组X线片、改进的GaryX线评分和光镜观察结果,以及术后第14周整骨破坏载荷和骨缺损修复形态学评分均明显优于DB组;但APBSC/DB组与ARBM/DB组间差异无显著性。结论 APBSC与ARBM都能在DB的骨形态蛋白诱导下促进成骨细胞的形成,复合移植疗效明显优于单纯DB移植。  相似文献   
98.
The hip joint dislocation is one of the most serious complications associated with severe type of spastic cerebral palsy in children. The natural history of this secondary problem is poorly defined: how often and why the dislocated hip joint is going to be painful. The aim of our study was to specify prevalence of hip pain in the quadriplegic spastic type of cerebral palsy children with dislocated one or two hip joints. The next purpose was to establish correlation between cartilage degenerative changes and pain appearance. MATERIAL AND METHOD: The clinical study population consisted of cerebral palsy children, who presented a unilateral or bilateral dislocation of the hip joint, operated in Department of Pediatric Orthopedics during the period 2002 through 2005. Performed surgical procedures allowed us to evaluate degenerative changes of femoral head cartilage. In 45 operated hips (33 patients) we discovered that 33 had degenerative cartilage lesions which in 25 cases (75%) were associated with pain appearance. RESULTS: We observed correlation between anterior location of the femoral head lesion and pain appearance, between the size of the lesion and intensity of pain complaints and also between femoral antetorsion and magnitude of pain. CONCLUSIONS: Risk factors of pain appearance in spastic dislocated hip joint are degenerative lesions on anterior face of femoral head cartilage, age of the patient, large antetorsion angle and cartilage lesion bigger than 1/4 of femoral head surface.  相似文献   
99.
100.
The paper presents the possibilities of applying the posterior thigh flap in the treatment of ischial pressure sores. Between 2000 and 2004 the flap was used in three cases treated in the Orthopaedics and Traumatology Department of the Medical Universtity in Bialystok. The indications, contraindications, operative technique and advantages of the posterior thigh flap are described. In all three cases the ischial bed sores healed well without recurrences. The posterior fasciocutaneous pedicled flap is a good method of treatment for not too extensive bed sores in the ischial region.This flap can be applied in recurrences found after primary bed sore treatment with another method. However the fasciocutaneous flap has a limited range of transposition as compared with cutaneous flaps.  相似文献   
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