Improving the Performance of Elbow Reconstruction

描述（由申请人提供）：全肘关节置换术（TEA）不像膝关节和髋关节置换术那样可预测或持久。不幸的是，其他治疗关节炎和手肘复杂创伤的方法效果更差。很少有人关注TEA失败，尽管伴随着这个问题的毁灭性残疾。失败的可能原因包括生物力学、患者和手术因素。但是，由于缺乏日常活动中手肘负荷的数据，难以评估这些因素的相对重要性，因此无法解释哪些因素是最有害的。尽管如此，最常见的失效模式，无菌性松动和过度聚乙烯磨损，表明生物力学因素占主导地位。因此，我们建议回答以下问题：生物力学、患者和手术因素如何影响全肘关节置换术中植入物的性能？为了回答这个问题，我们将使用综合方法来实现三个具体目标。首先，我们将联合收割机运动分析的TEA患者进行共同的活动与计算模型计算关节接触负荷。接下来，我们将这些载荷应用于植入TEA组件的肱骨和尺骨的数值模型，以检查骨水泥和骨中、界面处和聚乙烯关节表面处产生的应力，作为潜在植入物松动的测量。在进行这些分析时，我们将利用基于解剖学的方法，以及时和经济高效的方式检查重要的环境变量（关节载荷、组件位置和方向以及骨解剖结构和材料特性）。最后，我们将使用回顾性系列TEA失败病例的影像学观察结果以及取出的植入物组件的回收分析来确认我们分析中的机械失效模式。然后，我们可以破译哪些因素是重要的，在产生载荷和界面条件，解释为什么失败发生在特定区域内的骨植入系统。我们还将通过将我们的分析结果与回收聚乙烯部件的磨损和变形观察结果进行比较，解释哪些因素对关节面失效影响最大。从我们的研究中提供的信息，反过来，可以让我们更好地预测即将失败的患者谁已经经历了TEA，建议改变手术技术和仪器，以改善结果，并建议术后活动的限制，TEA患者应该考虑。然而，考虑到当代TEA的性能不佳，我们也可能会发现可以提高性能的设计变更。 公共卫生相关性：全肘关节置换术不像膝关节和髋关节置换术那样可预测或持久，但全肘关节置换术失败的失败通常是灾难性的，导致整个上肢严重残疾的连枷臂。我们的目的是解释生物力学，病人和手术因素，影响肘关节置换术的性能。我们的目标是解释失败的位置和机制，从而提出改善这种治疗效果的解决方案。

DESCRIPTION (provided by applicant): Total elbow arthroplasty (TEA) is not as predictable or durable as joint arthroplasties for the knee and hip. Unfortunately, other treatments for arthritis and complex trauma of the elbow are even less effective. Little attention has been paid to TEA failure, despite the devastating disability that accompanies the problem. Possible reasons for failure include biomechanical, patient, and surgical factors. But efforts to explain which factors are most detrimental are hampered by the lack of data on the loads across the elbow during routine daily activities, making it difficult to assess the relative importance of these factors. Nonetheless, the most prevalent failure modes, aseptic loosening and excessive polyethylene wear, suggest that biomechanical factors dominate. We propose, therefore, to answer the following question: How do biomechanical, patient, and surgical factors affect implant performance in total elbow arthroplasty? To answer this question, we will use an integrated approach to accomplish three specific aims. First, we will combine motion analysis of TEA patients performing common activities with a computational model to calculate the joint contact loads. Next, we will apply these loads to numerical models of the humerus and ulna implanted with TEA components to examine the stresses created in the cement and bone, at the interfaces, and at the polyethylene joint surfaces as measures of potential implant loosening. In performing these analyses, we will utilize statistically-based methods to examine important environmental variables (joint loads, component position and orientation, and bone anatomy and materials properties) in a timely and cost efficient manner. Finally, we will confirm the mechanical failure modes from our analyses using radiographic observations from a retrospective series of failed TEA cases together with retrieval analysis of the removed implant components. We can then decipher which factors are important in generating loads and interface conditions that explain why failures occur in particular areas within the bone-implant system. We will also explain which factors most affect bearing surface failure by comparing our analytical results with observations of wear and deformation on retrieved polyethylene components. The information provided from our study may, in turn, allow us to better predict impending failures in patients who have already undergone TEA, suggest alterations in surgical technique and instrumentation to improve outcomes, and suggest postoperative limits in activity that TEA patients should consider. As likely, however, given the poor performance of contemporary TEAs, we will also discover design alterations that will improve performance. PUBLIC HEALTH RELEVANCE: Total elbow replacement is not as predictable or durable as joint replacements for the knee and hip, yet failures of total elbow replacements failed elbow arthroplasty are usually catastrophic, resulting in a flail arm that severely disable the entire upper limb. We aim to explain biomechanical, patient, and surgical factors that affect the performance of elbow replacements. Our goal is to explain the locations and mechanisms of failure, thereby suggesting solutions to improve the efficacy of this treatment.