Changes in proximal tibia fracture strength as a function of time elapsed since s

近端胫骨骨折强度的变化作为自 s 以来经过的时间的函数

• 批准号: 8200836
• 负责人: William Brent Edwards
• 金额: $ 5.13万
• 依托单位: UNIVERSITY OF ILLINOIS AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2013-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8200836
• 关键词: Accounting; Affect; Agreement; Anatomy; Biological Models; Biomechanics; Bone Density; Bone Development; Chronic; Clinical; Complex; Cross-Sectional Studies; Data; Development; Distal; Elderly woman; Elements; Epidemiology; Event; Exercise; Failure; Femoral Fractures; Femur; Fracture; General Population; Goals; Hospitalization; Human; In Vitro; Incidence; Individual; Injury; Intervention; Lead; Lesion; Life; Location; Lower Extremity Fracture; Measurement; Measures; Methods; Minor; Modeling; Morbidity - disease rate; Motor; Neurologic; Population; Predictive Value; Quality of life; Radial; Regression Analysis; Research; Research Design; Risk; Risk Assessment; Scientist; Source; Specimen; Spinal cord injury; Statistical Models; Structure; Techniques; Tibial Fractures; Time; Trauma; Work; X-Ray Computed Tomography; active method; age related; base; bone; bone disuse atrophy; bone loss; bone mass; bone strength; density; experience; improved; in vivo; innovation; lifetime risk; medical complication; research study; skeletal; substantia spongiosa; tibia; tool

DESCRIPTION (provided by applicant): Spinal cord injury (SCI) is characterized by marked bone loss at regions below the neurological lesion. The clinical consequence of this reduction in bone is an increased lifetime risk for lower-extremity fracture due to minor trauma that is two times greater than the general population. Fracture risk assessment tools for the general public are inadequate for people living with SCI; the locations of routine fracture do not correspond between these two groups and bone density thresholds defining elevated fracture risk are typical of individuals with SCI. The ability to accurately quantify fracture strength in people with SCI could serve as an important clinical tool to assess fracture risk and objectively identify individuals that could safely participate in active treatment. The objectives of this application are to: Aim 1) develop a numerical method based on quantitative computed tomography (CT) capable of predicting fracture strength at the proximal tibia (a location commonly fractured following SCI), and Aim 2) quantify the change in fracture strength that occurs as a function of time elapsed since SCI. Aim 1 will be accomplished using a combined numerical-experimental study. Cadaveric proximal tibiae will be mechanically loaded until failure. Specimen-specific finite element models will be derived from CT data, and their ability to predict fracture strength determined from a regression analysis of numerical and experimental fracture loads. The predictive value of the finite element models will be compared to statistical models based on CT derived measures of bone mass, density, and structure. Aim 2 will be accomplished using a cross-sectional study design in which the fracture strength of individuals with motor complete SCI, as well as able-bodied controls, will be estimated from CT data. Reductions in fracture strength and bone parameters as a function of time since SCI will be quantified. The long-term goal of this research is to increase the quality of life for people living with SCI by minimizing the incidence of bone fracture in this population. This study will bring biomechanical relevance to the observed bone adaptive changes following SCI and help delineate the most critical determinants of bone fracture strength in this population. This will provide important information that can be used to help guide pharmacologic and exercise interventions that target adaptive changes in parameters most relevant to whole-bone fracture strength. In addition, because the SCI population serves as a model system for disuse osteoporosis, this work will increase our understanding of skeletal fracture in other populations having chronic bone loss and help guide the development of bone strengthening interventions for these individuals. PUBLIC HEALTH RELEVANCE: We propose to 1) develop new methods to quantify whole-bone fracture strength in people living with spinal cord injury, and 2) determine the changes in fracture strength that occur as a function of time elapsed since spinal cord injury. This work will increase our understanding of skeletal fracture in people having chronic bone loss and will facilitate the development of countermeasures to minimize the occurrence of skeletal fracture in this population.

描述（由申请人提供）：脊髓损伤（SCI）的特征是神经损伤下方区域明显的骨质流失。这种骨质减少的临床后果是，由于轻微创伤而导致下肢骨折的终生风险增加，是​​一般人群的两倍。面向公众的骨折风险评估工具对于 SCI 患者来说是不够的；这两组之间的常规骨折位置并不对应，定义骨折风险升高的骨密度阈值是 SCI 个体的典型特征。准确量化 SCI 患者骨折强度的能力可以作为评估骨折风险和客观识别可以安全参与积极治疗的个体的重要临床工具。本应用的目标是：目标 1) 开发一种基于定量计算机断层扫描 (CT) 的数值方法，能够预测胫骨近端（SCI 后常见骨折的位置）的骨折强度，目标 2) 量化骨折的变化强度是自 SCI 以来经过的时间的函数。目标 1 将通过数值实验相结合的研究来实现。尸体胫骨近端将受到机械负载直至失效。特定于样本的有限元模型将从 CT 数据中得出，并且它们预测断裂强度的能力是通过数值和实验断裂载荷的回归分析确定的。有限元模型的预测值将与基于 CT 导出的骨量、密度和结构测量值的统计模型进行比较。目标 2 将通过横断面研究设计来实现，其中将根据 CT 数据估计运动完全 SCI 个体以及健全对照者的骨折强度。自 SCI 以来，随着时间的推移，骨折强度和骨参数的降低将被量化。这项研究的长期目标是通过最大限度地减少 SCI 患者的骨折发生率来提高该人群的生活质量。这项研究将为观察到的 SCI 后骨适应性变化提供生物力学相关性，并帮助描述该人群骨折强度的最关键决定因素。这将提供重要信息，可用于帮助指导药理学和运动干预措施，以与全骨骨折强度最相关的参数的适应性变化为目标。此外，由于 SCI 人群作为废用性骨质疏松症的模型系统，这项工作将增加我们对其他慢性骨质流失人群骨骼骨折的了解，并有助于指导针对这些个体的骨强化干预措施的开发。 公共健康相关性：我们建议 1) 开发新方法来量化脊髓损伤患者的全骨骨折强度，2) 确定骨折强度随着脊髓损伤后经过的时间而发生的变化。这项工作将增加我们对慢性骨质流失人群骨骼骨折的了解，并将促进制定对策以尽量减少该人群骨骼骨折的发生。