Development of Mechanical Testing Systems to Perform Comprehensive Biomechanical Assessments of the Shoulder

与过去三十年来为髋关节、膝关节和脊柱开发的众多生物力学测试方法不同，肩关节测试系统相对较少且处于起步阶段。实验性肩关节器械通常在尸体样本上采用静态加载方案，以进行等长（即静止）测试。一些最近的系统已经使用简化的肌肉控制协议和/或机器人技术来产生手臂运动。然而，这些方法不能完全再现整个关节的肌肉负荷或实现足够的速度控制。此外，常见的动作，如手臂抬高，涉及旋转球窝（盂肱）关节，肩胛骨到躯干（肩胛胸）关节。这两种运动在实验环境中还没有很好地建立起来。这是合乎逻辑的假设，优化我们的理解和评估，这种联合需要先进的综合测试方法的开发和应用。因此，这项发现建议将集中在开发和应用新的肩部测试系统和测量技术的实验生物力学调查的肩膀。这些发展是一个重要的先驱，更完整地了解这个关节的生物力学。此外，植入物的开发和重建在很大程度上依赖于广泛的生物力学测试和分析。对于新型“反向”假肢尤其如此，其中头部和承窝反向，以在手臂抬高期间提供机械优势。虽然这些正在迅速普及，但需要更好的测试方法来更全面地了解其机械性能。这项研究的长期目标是阐明肩关节的生物力学，并提供一个强大的和全面的方法来评估。该提案的短期总体目标是开发和采用先进的肩关节测试系统和分析技术，以研究肩关节外展（手臂抬高）运动的生物力学，特别关注植入物测试。两个具体目标是：1）使用能够进行盂肱和肩胛胸运动的体外测试模拟器了解肩关节的生物力学。2)使用专门设计的内固定植入物系统确定肩关节植入物设计和定位如何影响关节载荷。本文提出的工作将导致新的发现有关的生物力学的肩膀的理解。这些发展也将导致最先进的测试程序的发展，这将允许广泛的先进的研究为基础的研究的肩膀。此外，拟议的详细调查将产生重要的结果和发现，这将有助于改进我的团队和其他人的测试方法和计算模型。最终，完成这一5年计划将很可能确保我们的实验室将继续在这种性质的研究中脱颖而出，并成为肩关节生物力学评估的世界领导者，在实验测试和建模的综合方法方面具有特殊的专业知识。

Unlike the multitude of biomechanical testing approaches that have been developed for the hip, knee, and spine over the past three decades, shoulder testing systems are relatively few and in their infancy. Experimental shoulder devices typically employ static loading protocols on cadaver specimens to produce isometric (i.e. stationary) testing. Some recent systems have produced arm motion using simplified muscle controlling protocols and/or robotics. However, these approaches do not fully reproduce muscle loading across the joint or achieve adequate velocity control. Moreover, common maneuvers such as arm elevation involve rotation of both the ball and socket (glenohumeral) joint, and the shoulder blade to trunk (scapulothoracic) articulation. These two motions have not been well established in the experimental setting. It is logical to postulate that optimizing our understanding and evaluation of this joint necessitates the development and application of advanced comprehensive testing approaches. Hence, this discovery proposal will focus on the development and application of novel shoulder-testing systems and measurement techniques for experimental biomechanical investigations of the shoulder. These developments are an important precursor to a more complete understanding of the biomechanics of this joint. Further, implant development and reconstruction relies heavily on extensive biomechanical testing and analyses. This is especially true of new “reverse” prosthesis where the head and socket are reversed to provide a mechanical advantage during arm elevation. While these are rapidly growing in popularity, better testing approaches are needed to more fully comprehend their mechanical performance. The long-term objective of this research is to elucidate the biomechanics of the shoulder and provide a robust and comprehensive approach to its evaluation. The short-term overall objective of this proposal is to develop and employ advanced shoulder-testing systems and analysis techniques to investigate the biomechanics of the shoulder for abduction (arm elevation) motion, with special interest in implant testing. The two specific objectives are: 1) To comprehend the biomechanics of the shoulder using an in-vitro testing simulator capable of both glenohumeral and scapulothoracic motion. 2) To establish how shoulder implant design and positioning affects joint loading using a specially designed instrumented implant system. The work proposed herein will lead to new discoveries related to the understanding of the biomechanics of the shoulder. These developments will also result in the evolution of a state of the art testing program that will permit a wide range of advanced research-based studies on the shoulder. Furthermore, the detailed investigations proposed will yield important results and findings that will contribute to improving testing approaches and computational models by my group and others. Ultimately, completion of this 5-year plan will very likely ensure that our laboratory will continue to excel in research of this nature, and be a world leader for the biomechanical assessment of the shoulder, with special expertise in comprehensive approaches to experimental testing and modelling.