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991.
目的比较长型PHILOS接骨板(Synthes公司,瑞士)扭转成螺旋形前后的生物力学特性,为临床治疗肱骨中上段骨折提供生物力学依据。方法 12例Synbone人工骨(SYNBONE公司,瑞士)的右侧肱骨平均分为两组,对照组(n=6)采用10孔的长型PHILOS接骨板固定,实验组(n=6)采用相同的接骨板扭转成螺旋形后固定。肱骨中上段骨折造模后,利用万能力学试验机分别检测并比较两组接骨板固定后的整体构件在轴向拉伸和压缩、同向和反向扭转、前后及内外向三点弯曲6种加载方式下的生物力学特性。结果在100~500 N拉伸和压缩载荷下,实验组骨折断端位移分别较对照组增加约95%和58%;在0.6~3 N·m反向扭矩下,实验组扭转角度始终明显小于对照组,减少幅度达到55%~64%;在0.6~3 N·m的同向扭矩和1.5~7.5 N·m的前后向弯矩下,实验组的扭转角度和桡度均大于对照组,差异有显著性意义(P0.05);当内外向弯矩为1.5、3 N·m时,实验组与对照组的桡度差别无显著性意义(P0.05),而内外向弯矩为4.5、6、7.5 N·m时,实验组的桡度较对照组小20%~30%。实验组与对照组构件相比,拉伸和压缩刚度分别低49%和36%,同向和反向扭转刚度分别低19%和高150%,内外向和前后向弯曲刚度分别高18%和低70%,差异均有显著性意义(P0.05)。结论长型PHILOS接骨板扭转成螺旋形后固定肱骨中上段骨折的总体力学性能有所改善,可以满足临床对该类骨折的手术固定和术后康复需要。结合微创手术的优势,该技术有望在临床得到广泛应用。  相似文献   
992.
目的 比较单、双侧接骨板治疗干骺端粉碎股骨远端骨折的生物力学稳定性。方法22根人工股骨标本建立干骺端粉碎股骨远端骨折(AO分型:C2.3)模型,随机分成2组,每组11根。单钢板组用外侧远端解剖锁定板固定,双钢板组外侧用远端解剖锁定板、内侧用直型锁定接骨板固定。每组标本中5根进行垂直加压,3根进行循环垂直加压测试,检测干骺端内侧间隙压缩位移,剩余3根进行极限加压测试,记录固定失败时的最大负荷。结果 垂直加压测试中,单钢板组平均内侧压缩位移为(2.61±0.28) mm,双钢板组为(0.46±0.08) mm。循环垂直加压测试中,单钢板组平均内侧压缩位移为(1.56±0.12) mm,双钢板组为(0.43±0.05) mm。极限加压测试中,单钢板组平均最大负荷为(5 567±338) N,双钢板组为(9 147±186) N,每组差异都有统计学意义(P<0.05)。结论 双钢板固定干骺端粉碎股骨远端骨折的内侧抗压缩能力较单钢板固定显著增强,使股骨远端内侧结构更加稳定,有助于病人早期功能康复锻炼。  相似文献   
993.
994.
OBJECTIVES: To establish and validate a method of linking data from the Minimum Data Set (MDS) and Medicare hospital claims, to estimate hip fracture incidence rates for Medicare beneficiaries aged 65 and older in Washington State, and to compare the incidence rates of hip fractures in nursing home and non-nursing home residents. DESIGN: Retrospective analysis of Medicare population-based enrollment, hospital claims, and nursing home administrative data sets. SETTING: Nursing home and non-nursing home setting. PARTICIPANTS: Medicare beneficiaries in Washington State residing in the community or in skilled nursing facilities. MEASUREMENTS: Crude age- and sex-specific and standardized age- and sex-adjusted hip fracture incidence for persons residing and not residing in nursing homes. RESULTS: From October 1, 1993, through September 30, 1995, 7,812 Medicare beneficiaries aged 65 or older were hospitalized for hip fractures (6,566 fractures for 1,155,234 person-years of exposure in non-nursing home residents and 1,246 fractures for 42,986 person-years of exposure in nursing home residents). The standardized age- and sex-adjusted hip fracture rate of nursing home residents (23.0 per 1,000 person-years) substantially exceeded that of non-nursing home residents (5.7 per 1,000 person-years) (incidence rate ratio = 4.0, 95% confidence interval = 3.7-4.5). CONCLUSION: The incidence of hip fracture in nursing home residents far exceeds that in noninstitutionalized older people. Linkage of MDS and Medicare hospital claims data is a useful tool for epidemiological surveillance regarding events in nursing homes that are likely to result in hospitalization.  相似文献   
995.
Introduction:Human Immunodeficiency Virus (HIV) infection remains prevalent co-morbidity, and among fracture patients. Few studies have investigated the role of exercise interventions in preventing bone demineralization in people who have fractures and HIV. If exercise exposed, HIV-infected individuals may experience improved bone health outcomes (BMD), function, quality of life (QoL). The study will aim to assess the impact of home based exercises on bone mineral density, functional capacity, QoL, and some serological markers of health in HIV infection among Nigerians and South Africans.Methods and design:The study is an assessor-blinded randomized controlled trial. Patients managed with internal and external fixation for femoral shaft fracture at the study sites will be recruited to participate in the study. The participants will be recruited 2 weeks post-discharge at the follow-up clinic with the orthopaedic surgeon. The study population will consist of all persons with femoral fracture and HIV-positive and negative (HIV-positive medically confirmed) aged 18 to 60 years attending the above-named health facilities. For the HIV-positive participants, a documented positive HIV result, as well as a history of being followed-up at the HIV treatment and care center. A developed home based exercise programme will be implemented in the experimental group while the control group continues with the usual rehabilitation programme. The primary outcome measures will be function, gait, bone mineral density, physical activity, and QoL.Discussion:The proposed trial will compare the effect of a home-based physical exercise-training programme in the management of femoral fracture to the usual physiotherapy management programmes with specific outcomes of bone mineral density, function, and inflammatory markers.Trial registration:The study was prospectively registered with the Pan African Clinical Trials Registry (Reference number – PACTR201910562118957) on October 21, 2019. (https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=9425).  相似文献   
996.
目的 探讨家庭-社会支持对3D打印辅助个体化定制治疗复杂创伤骨折患者心理应激的影响。 方法 以2015年1月-2017年2月我院收治的80例复杂创伤骨折患者为对象,按随机数字表法将其分为对照组和观察组各40例,2组均接受3D打印辅助个体化定制治疗,对照组实施认知行为干预,观察组在对照组基础上给予家庭-社会支持,比较干预前后2组汉密尔顿抑郁量表(Hamilton depression scale, HAMD)及汉密尔顿焦虑量表(Hamilton anxiety scale, HAMA)评分、视觉模拟疼痛(visual analogue scale/score, VAS)评分及生活质量调查问卷(the EORTC quality of life questionnaire-core 30,EORTC QLQ-C30)评分。 结果 干预后,2组HAMD、HAMA、VAS评分均低于对照组, EORTC QLQ-C30评分高于对照组。 结论 家庭-社会支持应用于3D打印辅助治疗复杂创伤骨折患者中,在改善其心理应激、术后疼痛和预后等方面具有积极作用,在临床中有推广应用价值。  相似文献   
997.
998.
Distal limb fracture is the most common cause of complex regional pain syndrome (CRPS), thus the rodent tibia fracture model (TFM) was developed to study CRPS pathogenesis. This comprehensive review summarizes the published TFM research and compares these experimental results with the CRPS literature. The TFM generated spontaneous and evoked pain behaviors, inflammatory symptoms (edema, warmth), and trophic changes (skin thickening, osteoporosis) resembling symptoms in early CRPS. Neuropeptides, inflammatory cytokines, and nerve growth factor (NGF) have been linked to pain behaviors, inflammation, and trophic changes in the TFM model and proliferating keratinocytes were identified as the primary source of cutaneous cytokines and NGF. Tibia fracture also activated spinal glia and upregulated spinal neuropeptide, cytokine, and NGF expression, and in the brain it changed dendritic architecture. B cell-expressed immunoglobulin M antibodies also contributed to pain behavior, indicating a role for adaptive immunity. These results modeled many findings in early CRPS, but significant differences were also noted.

Perspective

Multiple neuroimmune signaling mechanisms contribute to the pain, inflammation, and trophic changes observed in the injured limb of the rodent TFM. This model replicates many of the symptoms, signs, and pathophysiology of early CRPS, but most post-fracture changes resolve within 5 months and may not contribute to perpetuating chronic CRPS.  相似文献   
999.

Background

Emergency departments rely on CT scans to manage trauma victims, especially for head injuries. Although the detection of an undisplaced fracture on a CT scan of the head without significant intracranial findings may be insignificant for a clinician, such cases are of paramount importance for medico-legal purposes because they help ascertain the nature, manner, and cause of the head injury.

Aims

The study was conducted with the objective of knowing the sensitivity and specificity of ante-mortem CT scan findings indicating the presence or absence of skull fractures.

Methods

Findings were confirmed during post-mortem examination of the subjects who had died during management but who had not had any surgical intervention. A comparative study of ante-mortem CT scan and autopsy findings with respect to fracture in traumatic head injuries was undertaken on 60 deceased individuals brought in for medico-legal post-mortem examination over a period of two years.

Results

Considering the autopsy findings as the gold standard, we have concluded that 14.6 per cent of the fractures were missed on CT scan findings compared to fractures found during autopsy. The sensitivity of CT scan for skull fractures was found to be 85.4 per cent and specificity was 100 per cent. Kappa was 0.787, which shows good agreement with p<0.001, which was highly significant.

Conclusion

In developing countries, images are interpreted in the axial plane only on a CT scan of the head, which may be due to a lack of financial and human resources. For better delineation of fractures, the use of techniques like multi-detector CT with sagittal and coronal reformations should be considered in the routine interpretation of a CT scan of the head.  相似文献   
1000.
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