Name: method and instrumented fixture for femoral fracture testing in a sideways fall-on-the-hip position
Uploaded: 2017-08-17T12:30:00
Description: Watch this Scientific Journal Video about Method and Instrumented Fixture for Femoral Fracture Testing in a Sideways Fall-on-the-Hip Position at JoVE.com

我们想感谢的材料和结构测试核心设施和工程在梅奥诊所司的技术支持。此外，我们想感谢劳伦斯 J.殷勤，詹姆斯 · 布朗，布兰特纽曼，Jorn op den Buijs，博士学位，他们在研究期间的帮助。这项研究提供了由格兰杰基金会从固安捷创新基金资助。

1.大型夹具附件 <ol><li>从机器中删除标准夹具。</li>
	<li>移动十字头分开以适应内部夹具。</li>
	<li>将铝块 （在 图 1A 部分号 1） 放在机器上和牢固地扣上使用两个螺栓机; 在中心孔可容纳机负载细胞。</li>
	<li>在铝块上放置主要夹具结构 （在 图 1B 第第 2 部分） 和安全地将它附加到块中使用 4 根螺栓。</li>
	<li>放置四吨杰克下不休息在铝块支持夹具 ...

<ol>
	<li>Bouxsein, M. L., Szulc, P., Munoz, F., Thrall, E., Sornay-Rendu, E., Delmas, P. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Contribution+of+trochanteric+soft+tissues+to+fall+force+estimates,+the+factor+of+risk,+and+prediction+of+hip+fracture+risk.">Contribution of trochanteric soft tissues to fall force estimates, the factor of risk, and prediction of hip fracture risk.</a> J Bone Miner Res. 22, 825-831 (2007).</li><li>Rezaei, A., Dragomir-Daescu, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Femoral+Strength+Changes+Faster+With+Age+Than+BMD+in+Both+Women+and+Men:+A+Biomechanical+Study.">Femoral Strength Changes Faster With Age Than BMD in Both Women and Men: A Biomechanical Study.</a> J Bone Miner Res. 30, 2200-2206 (2015).</li><li>Zani, L., Erani, P., Grassi, L., Taddei, F., Cristofolini, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Strain+distribution+in+the+proximal+Human+femur+during+in+vitro+simulated+sideways+fall.">Strain distribution in the proximal Human femur during in vitro simulated sideways fall.</a> J Biomech. 48, 2130-2143 (2015).</li><li>Dragomir-Daescu, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Robust+QCT/FEA+models+of+proximal+femur+stiffness+and+fracture+load+during+a+sideways+fall+on+the+hip.">Robust QCT/FEA models of proximal femur stiffness and fracture load during a sideways fall on the hip.</a> Ann Biomed Eng. 39, 742-755 (2011).</li><li>Schileo, E., Balistreri, L., Grassi, L., Cristofolini, L., Taddei, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=To+what+extent+can+linear+finite+element+models+of+human+femora+predict+failure+under+stance+and+fall+loading+configurations?.">To what extent can linear finite element models of human femora predict failure under stance and fall loading configurations?.</a> J Biomech. 47, 3531-3538 (2014).</li><li>Koivumaki, J. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ct-based+finite+element+models+can+be+used+to+estimate+experimentally+measured+failure+loads+in+the+proximal+femur.">Ct-based finite element models can be used to estimate experimentally measured failure loads in the proximal femur.</a> Bone. 50, 824-829 (2012).</li><li>Pottecher, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prediction+of+Hip+Failure+Load:+In+Vitro+Study+of+80+Femurs+Using+Three+Imaging+Methods+and+Finite+Element+Models—The+European+Fracture+Study+(EFFECT).">Prediction of Hip Failure Load: In Vitro Study of 80 Femurs Using Three Imaging Methods and Finite Element Models—The European Fracture Study (EFFECT).</a> Radiology. , 142796 (2016).</li><li>Rivadeneira, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Femoral+neck+BMD+is+a+strong+predictor+of+hip+fracture+susceptibility+in+elderly+men+and+women+because+it+detects+cortical+bone+instability:+the+Rotterdam+Study.">Femoral neck BMD is a strong predictor of hip fracture susceptibility in elderly men and women because it detects cortical bone instability: the Rotterdam Study.</a> J Bone Miner Res. 22, 1781-1790 (2007).</li><li>de Bakker, P. M., Manske, S. L., Ebacher, V., Oxland, T. R., Cripton, P. A., Guy, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=During+sideways+falls+proximal+femur+fractures+initiate+in+the+superolateral+cortex:+evidence+from+high-speed+video+of+simulated+fractures.">During sideways falls proximal femur fractures initiate in the superolateral cortex: evidence from high-speed video of simulated fractures.</a> J Biomech. 42, 1917-1925 (2009).</li><li>Courtney, A. C., Wachtel, E. F., Myers, E. R., Hayes, W. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Age-related+reductions+in+the+strength+of+the+femur+tested+in+a+fall-loading+configuration.">Age-related reductions in the strength of the femur tested in a fall-loading configuration.</a> J Bone Joint Surg Am. 77, 387-395 (1995).</li><li>Cheng, X. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assessment+of+the+strength+of+proximal+femur+in+vitro:+relationship+to+femoral+bone+mineral+density+and+femoral.">Assessment of the strength of proximal femur in vitro: relationship to femoral bone mineral density and femoral.</a> Bone. 20, 213-218 (1997).</li><li>Courtney, A. C., Wachtel, E. F., Myers, E. R., Hayes, W. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+loading+rate+on+strength+of+the+proximal+femur.">Effects of loading rate on strength of the proximal femur.</a> Calcif Tissue Int. 55, 53-58 (1994).</li><li>Keyak, J., Rossi, S., Jones, K., Les, C., Skinner, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prediction+of+fracture+location+in+the+proximal+femur+using+finite+element+models.">Prediction of fracture location in the proximal femur using finite element models.</a> Medical engineering &amp; physics. 23, 657-664 (2001).</li><li>Nishiyama, K. K., Gilchrist, S., Guy, P., Cripton, P., Boyd, S. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Proximal+femur+bone+strength+estimated+by+a+computationally+fast+finite+element+analysis+in+a+sideways+fall+configuration.">Proximal femur bone strength estimated by a computationally fast finite element analysis in a sideways fall configuration.</a> J Biomech. 46, 1231-1236 (2013).</li><li>Langton, C. M., Njeh, C. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The physical measurement of bone. , (2016).</li><li>Ariza, O., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+explicit+finite+element+and+mechanical+simulation+of+the+proximal+femur+during+dynamic+drop-tower+testing.">Comparison of explicit finite element and mechanical simulation of the proximal femur during dynamic drop-tower testing.</a> J Biomech. 48, 224-232 (2015).</li></ol>

我们提出了一项议定书，断裂测试尸体股骨近端在秋天的髋关节的配置，我们已经成功地测试了大约 200 个样本。议定书 》 包括几个内部设计的夹具为股骨强度在不同加载条件下的试验。夹具允许测试在不同的测试速度和骨方向的左边和右边股骨。后安装夹具和测量仪器，测试的玻璃纤维股骨骨折以确保所有的硬件和软件工具正确连接，同步，工作和正确地记录的信号和视频。只是之前实际尸体...

股骨骨折风险评估的新方法及落在髋关节骨折预防发展需要对断裂过程中所涉及的生物力学过程的全面理解。尸体股骨近端强度测试已被证明是有效地确定股骨强度与股骨提供重要的见解，在此过程1，2结构承载能力影响因素之间的关系,3.实验测量股骨强度也可用于验证的基于定量计算层析成像的有限元分析 (QCT/FEA) 使断裂强度4，5，一个非侵入性的估计 6，7。
到目前为止，并无接受的标准程序来测试整个股骨标本骨折。要隔离临床可以衡量变量 （例如骨密度和几何） 和他们对股骨强度的影响，是实验测试必须以可控和可重复的方式进行。尸体股骨有不规则的形状和范围大小8中，可以索取使它无法使用内置固定装置的标准试验机测试不同年龄段的男性或女性尸体。在横盘落在髋关节事件，股骨大转子经历时股骨近端可能会遇到复杂的载荷，包括压缩、 张力、 弯矩和扭矩，压缩加载。测试这种加载场景添加实验设计的复杂性。因此，夹具，作为一个重要组成部分的测试协议，必须专门设计、 捏造，并安装以容纳股样本的不同形状和大小的不同的测试速度。此夹具也必须持有标本测试所需的方向来模拟放在臀部上坠落可能冲击载荷范围内。要满足各种各样的条件，需要有多个固定夹具和运动部件连接尽量发挥在系统中，获得平滑的荷载-位移响应的方式。
在测试过程中，可靠的数据采集也是关键的。实验设计必须纳入必要的负载细胞、 位移传感器、 信号放大器和改良剂对准确地测量力和力矩根本支持。此外，高速视频获得同步采集的部队与股骨的前部和后部意见是必要的有助于了解导致骨折，鉴定骨折类型，事件的顺序和精确定义股骨强度4，9。
虽然有宝贵的实验研究在文献中对整个股骨测试，已发布的协议要么缺乏细节上如何进行了测试，要么是非常不同的从一项研究的另一个，真正使他们重现10， 11。当前工作的目标是介绍机械测试可以作为努力的起点用于标准化测试的可重复性和可再现的骨组织的股骨样品的协议。为此，我们设计和制作测试夹具，用于测试约 200 尸体股骨。测试夹具包括底部夹具和十字头夹具。底部夹具 （图 1A-E） 举行股骨在测试过程中所需的方向，包括转子负荷细胞和连接到股骨干 6 信道负载细胞。它还可容纳三个独立的翻译，以便定位的骨骨折测试。旋转点添加到模仿膝关节。底部夹具的主要部分被组成的厚片的不锈钢和铝，使非常僵硬的夹具。负载细胞被附加到底部夹具在测试过程中测量股骨大转子上的压缩力。十字头夹具 (图 2A-2E) 包括两个铝基座和两个非常僵硬幻灯片球轴承 （连接在一起的铝板），在测试过程中占股骨头的运动，容纳为左、 右股骨。负载单元格包括在十字头夹具措施压缩力。附加到负载单元格铝杯用于将压缩荷载传递到股骨头。我们的方法用于男女各种尺寸与左、 右股骨、 颈干角，骨密度，和加载条件模仿侧身落在臀部。在我们的实验测试速度为 5、 100 和 700 毫米/秒，但他们可以设置为任何值的测试计算机上可用。设计工装夹具有两个主要组件，一个连接到测试机十字头和其他连接到测试框架。两个部分被即刻负载细胞足以测量力和力矩边界条件在所有支持。此外，两个高速摄像机被用来在测试过程中记录断裂事件。骨折后，一套 x 射线和计算层析成像 (CT) 扫描后实验性骨折分析得到了。结果从这些实验包括断裂强度和能源目前用于额外的诊断工具的研究，最终改善骨质疏松症患者近端断裂强度的评估。

<table>
	<tbody>
		<tr>
			<td>CT scanner</td>
			<td>Siemens</td>
			<td>Somatom Definition scanner (Siemens, Malvern, PA)</td>
			<td>CT scanning equipment</td>
		</tr>
		<tr>
			<td>Quantitative CT Phantom</td>
			<td>Midways Inc, San Francisco, CA</td>
			<td>Model 3 CT calibration Phantom</td>
			<td>Used for obtaining BMD values from Hounsfield units in the CT image</td>
		</tr>
		<tr>
			<td>Hygenic Orthodontic Resin (PMMA)</td>
			<td>Patterson Dental Supply</td>
			<td>H02252</td>
			<td>Controlled substance and can be purchased with proper approval</td>
		</tr>
		<tr>
			<td>Freezer</td>
			<td>Kenmore</td>
			<td>N/A</td>
			<td>This is a -20oC storage for bones</td>
		</tr>
		<tr>
			<td>X-ray scanner</td>
			<td>General Electric</td>
			<td>46-270615P1</td>
			<td>X-ray imaging equipment.</td>
		</tr>
		<tr>
			<td>X-ray films</td>
			<td>Kodak</td>
			<td>N/A</td>
			<td>Used to display x-ray images</td>
		</tr>
		<tr>
			<td>X-ray developer</td>
			<td>Kodak X-Omatic</td>
			<td>M35A X-OMAT</td>
			<td>Used for developing X-ray images</td>
		</tr>
		<tr>
			<td>X-ray Cassette</td>
			<td>Kodak X-Omatic</td>
			<td>N/A</td>
			<td>Used for holding x-ray films</td>
		</tr>
		<tr>
			<td>Physiologic Saline (0.9% Sodium Chloride)</td>
			<td>Baxter</td>
			<td>NDC 0338-0048-04</td>
			<td>Used for keeping samples hydrated</td>
		</tr>
		<tr>
			<td>Scalpels and scrapers</td>
			<td>Bard-Parker</td>
			<td>N/A</td>
			<td>Used to clean the bone from soft tissue</td>
		</tr>
		<tr>
			<td>Fume Hood</td>
			<td>Hamilton</td>
			<td>70532</td>
			<td>Used for ventilation when preparing PMMA for potting of specimens</td>
		</tr>
		<tr>
			<td>Single axis load cell</td>
			<td>Transducer Techniques, Temecula, CA, USA</td>
			<td>LPU-3K; S/N 219627</td>
			<td>Capacity 3000 LBS</td>
		</tr>
		<tr>
			<td>Six channel load cell</td>
			<td>JR3,Woodland, CA</td>
			<td>45E15A4</td>
			<td>Mechanical load rating 1000N</td>
		</tr>
		<tr>
			<td>Linear potentiometer</td>
			<td>Novotechnik, Southborough, MA, USA</td>
			<td></td>
			<td>Used to acquire linear displacements during testing</td>
		</tr>
		<tr>
			<td>Slide ball bearing</td>
			<td>Schneeberger</td>
			<td>Type NK</td>
			<td>Part of the testing fixture</td>
		</tr>
		<tr>
			<td>Mechanical testing machine</td>
			<td>MTS, Minneapolis, MN</td>
			<td>858 Mini Bionix II</td>
			<td>Used for compression of femur</td>
		</tr>
		<tr>
			<td>Lighting unit</td>
			<td>ARRI</td>
			<td></td>
			<td>Needed for high speed video recordings</td>
		</tr>
		<tr>
			<td>high-speed video camera</td>
			<td>Photron Inc., San Diego, CA, USA</td>
			<td>Photron Fastcam APX-RS</td>
			<td>Used to capture the high speed video recordings of the fracture events</td>
		</tr>
		<tr>
			<td>Photron FASTCAM Viewer</td>
			<td>Photron Inc., San Diego, CA, USA</td>
			<td>Ver.3392(x64)</td>
			<td>Used to view the high speed video recordings</td>
		</tr>
		<tr>
			<td>Camera lens</td>
			<td>Zeiss</td>
			<td>Zeiss Planar L4/50 ZF Lens</td>
			<td>Needed to high image resolution</td>
		</tr>
		<tr>
			<td>Signal conditioner board (DAQ)</td>
			<td>National Instruments</td>
			<td></td>
			<td>Input/output signal connector</td>
		</tr>
		<tr>
			<td>Signal Express</td>
			<td>National Instruments</td>
			<td>N/A</td>
			<td>Data acquisition software</td>
		</tr>
		<tr>
			<td>Laptop Computer</td>
			<td>Dell</td>
			<td>N/A</td>
			<td>Used to monitor and acquire all signals from the testing procedure</td>
		</tr>
	</tbody>
</table>

method and instrumented fixture for femoral fracture testing in a sideways fall-on-the-hip position

机械测试的股骨带来有价值的见解，了解临床可以衡量的变量，例如骨矿物密度分布和几何形状对股骨力学性能的贡献。目前，尚没有用于这种措施强度和刚度的几何复杂骨头的机械试验标准协议。为了缩小这种差距我们制订了一项议定书，尸体股骨骨折并衡量其生物力学参数测试。此协议说明一套适应性强的夹具，以容纳不同的负载大小和方向为可能的骨方向在秋天会计髋关节配置，测试速度、 骨大小和左的腿右腿变化。股骨准备测试由清洗、 切割、 扫描和灌封的远端和股骨大转子接触表面在 poly(methyl methacrylate))，提出在不同的协议。准备好的标本被放置在测试夹具中模仿侧身落在臀部的位置和加载断裂。在测试期间，两个负载细胞测量垂直力适用于股骨头和股骨大转子、 六轴负载细胞测量的部队，并时刻在股骨远端和位移传感器测量差动位移之间股骨头和股骨转子区联系支持。高速摄像机被用来同步记录在测试过程中的断裂事件发生的顺序。这种数据减少允许我们进行归类的强度、 刚度，和断裂能的近 200 骨质疏松，骨质疏松，和正常的尸体股骨，为进一步发展基于工程的骨质疏松症的诊断工具的研究。

内部的夹具安装后标夹具从试验机中删除。第一，底部重夹具是安装和固定 (图 1)。这包括扩展的手臂想站 6 通道负载细胞，这也使股骨在预期内收角对齐。下一步，包括两个无摩擦滑动轴承十字头夹具安装以适应应用程序的负载和股骨头部的动作期间骨折 (图 2)。上部的夹具是可调的测试左和右腿。一旦所有夹具都安装，安装...

Watch this Scientific Journal Video about Method and Instrumented Fixture for Femoral Fracture Testing in a Sideways Fall-on-the-Hip Position at JoVE.com

Method and Instrumented Fixture for Femoral Fracture Testing in a Sideways Fall-on-the-Hip Position

在这份手稿，我们提出一项议定书，在髋关节的配置使用标准伺服液压架上安装检测的夹具侧身摔倒骨折试验尸近端股骨。在测试过程中采集包括部队、 时刻和位移以及两个高速视频流的九个数字化的信号。

方法和股骨骨折测试在横盘整理的秋天在臀部位置检测的夹具

Mechanical testing of femora brings valuable insights into understanding the contribution of clinically-measureable variables such as bone mineral density ...

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Force System Resultants

SCIENTISTS IN ACTION

A Method for Ovarian Follicle Encapsulation and Culture in a Proteolytically Degradable 3 Dimensional System

卵泡在蛋白质降解的3维系统的封装和文化的一种方法

The ovarian follicle is the functional unit of the ovary that secretes sex hormones and supports oocyte maturation. In vitro  follicle techniques provide ...

科研

生物工程

Creating Two-Dimensional Patterned Substrates for Protein and Cell Confinement

蛋白质和细胞坐月子创建二维图案衬底

Microcontact printing provides a rapid, highly reproducible method for the creation of well-defined patterned substrates.1  While microcontact printing ...

Environmentally-controlled Microtensile Testing of Mechanically-adaptive Polymer Nanocomposites for ex vivo Characterization

Environmentally-controlled Microtensile Testing of Mechanically-adaptive Polymer Nanocomposites for ex vivo Characterization

环境控制机械自适应聚合物纳米复合材料的微拉伸测试<em&gt;体外</em&gt;表征

Implantable microdevices are gaining significant attention for several biomedical applications1-4. Such devices have been made from a range of materials, ...

Determination of the Transport Rate of Xenobiotics and Nanomaterials Across the Placenta using the ex vivo Human Placental Perfusion Model

Determination of the Transport Rate of Xenobiotics and Nanomaterials Across the Placenta using the ex vivo Human Placental Perfusion Model

通过胎盘的外来物质和纳米材料的运输率测定<em&gt;体外</em&gt;人胎盘灌注型号

Decades ago the human placenta was thought to be an impenetrable barrier between mother and unborn child. However, the discovery of thalidomide-induced ...

An Improved Mechanical Testing Method to Assess Bone-implant Anchorage

一种改进的机械性能测试方法来评估骨种植体支抗

Recent advances in material science have led to a substantial increase in the topographical complexity of implant surfaces, both on a micro- and a ...

A Method to Estimate Cadaveric Femur Cortical Strains During Fracture Testing Using Digital Image Correlation

基于数字图像相关的骨折检测中股骨皮质应变的估算方法

This protocol describes the method using digital image correlation to estimate cortical strain from high speed video images of the cadaveric femoral ...

A Reliable and Reproducible Critical-Sized Segmental Femoral Defect Model in Rats Stabilized with a Custom External Fixator

一种可靠、可重复的可重复的大鼠部分股骨缺陷模型

Orthopedic research relies heavily on animal models to study mechanisms of bone healing in vivo as well as investigate the new treatment techniques. ...

Simultaneous Quantification of Selected Kynurenines Analyzed by Liquid Chromatography-Mass Spectrometry in Medium Collected from Cancer Cell Cultures

从癌细胞培养物中收集的介质光谱分析的选定金核素的同步量化

The kynurenine pathway and the tryptophan catabolites called kynurenines have received increased attention for their involvement in immune regulation and ...

Advanced 3D Liver Models for In vitro Genotoxicity Testing Following Long-Term Nanomaterial Exposure

长期纳米材料暴露后体外基因毒性测试的高级 3D 肝脏模型

Due to the rapid development and implementation of a diverse array of engineered nanomaterials (ENM), exposure to ENM is inevitable and the development of ...

Cantilever Bending of Murine Femoral Necks

鼠股颈悬臂弯曲

Fractures in the femoral neck are a common occurrence in individuals with osteoporosis. Many mouse models have been developed to assess disease states and ...