Analysis and Optimization of the Pavlik Harness Treatment of Neonates with Hip Dysplasia

Pavlik背带是世界范围内用于非手术矫正婴儿先天性髋关节发育不良（CHD）的标准矫形装置，但其作用机制尚未研究，因此了解甚少。结果，大约15%的患者使用这种装置治疗失败。近76%的髋关节骨关节炎病例归因于早期未治疗的髋关节发育不良，这种残疾通常需要在50岁之前进行全髋关节置换术。据估计，近1/20的足月婴儿出生时患有某种类型的髋关节不稳定，其中1000人中有2-3人需要治疗，近15%的婴儿因冠心病治疗失败，最终导致Pavlik背带导致残疾。考虑到该设备的失败率是髋关节骨关节炎导致残疾的主要原因，我们建议将我们为期一年的初步研究结果作为基础，参与本文提出的研究项目，我们将利用工程基础知识，根据从患有冠心病的婴儿的个体ct扫描中提取的数据，开发一种针对冠心病病例的治疗方法。为此，我们建议：(1)根据患者特定的婴儿几何形状，考虑到肌肉组织的大变形和非线性行为，建立一个由Pavlik线束施加的载荷引起的髋部动态生理反应的有限元模型；(2)制定一个基于最小能量原理的自动化算法，以确定最佳的Pavlik线束载荷分量，从而成功地将股骨头导向其在髋臼中的正确生理位置；同时在整个治疗过程中保持髋关节复位，并且(3)建立所提出的fem优化方法作为规划工具，以实现计算确定患者特定的Pavlik安全带最佳配置的目标，使最佳配置转移到接受婴儿，帮助治疗的成功。这也将有助于培训医生成功地使用和应用帕夫利克挽具。智力价值：该项目的主要智力价值是期望我们的研究将提供对冠心病成功治疗机制的洞察，并提出可行的临床方法，旨在降低使用Pavlik治疗失败率。由于这种常见的骨科装置的作用机制尚未进行表征，因此本项目的研究结果将是对冠心病认识和治疗的一个突破。我们设计了一个多学科框架，通过有限元建模将工程分析结合在一起，为每位患者预测Pavlik线束几何形状的最佳配置，并指导治疗计划。尽管最优？配置不是通用的，我们将设计一种通用的针对特定患者的治疗计划程序。另一个智力上的优点是，这是一个真正的跨学科研究项目，汇集了医学专业人员和工程师，以一种综合和互补的方式，提供了一个基于物理的框架来解决实际的医学问题，其解决方案对大量患者群体有关键影响。更广泛的影响：该项目对社会的主要影响将是最终改善使用帕夫利克挽具进行矫正治疗的冠心病患者的生活质量。本研究提供了一种实用的解决方案，利用工程专业知识和建模能力，将医疗投入和知识结合起来，实现有效的治疗。此外，由于美国每年进行12万例全髋关节置换术，婴儿冠心病的早期发现和非手术矫正可以潜在地避免随后巨大的健康相关费用。此外，研究生和本科生将沉浸在一个高度跨学科的工作环境中，因为就其本质而言，该项目要求学生在一个对社会重要的现实问题中综合学习几门工程课程和物理科学。学生们非常渴望参与到工程和医学相结合的项目中来。合作项目的生物工程研究活动吸引了许多学生，其中包括几名女性和西班牙裔学生，其中几名学生赢得了科学和工程技术竞赛，其中一名学生就本拨款提案的主题进行了试点研究。加州大学旧金山分校的工程与计算机科学学院（CECS）被《西班牙裔商业杂志》（hispanic Business Magazine）评为美国第三大拉美裔学生的首选学院，该项目为招收生物工程领域的拉美裔学生提供了一种独特的方式。

PI: KassabProposal 1160179The Pavlik harness is the standard orthopaedic device utilized worldwide to non-surgically correct congenital hip dysplasia (CHD) in infants, but its mechanism of action has not been studied, and is therefore little understood. As a result, treatment with this device fails for about 15% of the patients. Nearly 76% of hip osteoarthritis cases are attributed to untreated hip dysplasia at an early stage in life and this disability usually requires total hip replacement before the age of 50. It is estimated that nearly 1/20 full term infants are born with some type of hip instability, of which 2-3 out of 1000 will require treatment, and that nearly 15% will fail treatment for CHD with the Pavlik Harness leading to disability as the ultimate consequence. Accepting the rate of failure of this device as a leading cause of disability as a result of hip osteoarthritis, we propose to use the results of our year-long preliminary study as the foundation to engage in the hereby proposed research project where we will use engineering fundamentals to develop a case-specific approach to the treatment of CHD based on data extracted from individual CT-scans of infants afflicted by the condition. To do this we propose to: (1) develop a finite element model of the dynamic physiological response of the hip due to loads imposed by the Pavlik harness based on patient specific infant geometry, accounting for large deformation and non-linear behavior of the musculature, (2) formulate an automated algorithm based on the principle of minimum energy to determine optimum Pavlik harness load components necessary to successfully vector the femoral heads into their correct physiological position in the acetabula, while maintaining hip reduction for the full length of treatment, and (3) establish the proposed FEM-optimization methodology as a planning tool to achieve the goal of computationally determining patient-specific optimal configuration of the Pavlik harness allowing the optimum configuration to be transferred to the recipient infant, aiding in the success of the treatment. This will also serve in training physicians to successfully use and apply the Pavlik Harness.Intellectual Merit: The primary intellectual merit of this project is the expectation that our study will provide insight into the mechanisms of the successful treatment of CHD and suggest feasible clinical methods aimed at reducing the rate of failure of the treatment with the Pavlik Harness. Because no characterization has been made of the mechanism of action of this common orthopaedic device, the results of this project would constitute a breakthrough in the understanding and treatment of CHD. We have devised a multi-disciplinary framework, bringing together engineering analysis via finite element modeling, to predict optimal configuration of the Pavlik Harness geometry for each patient and serving to guide treatment planning. Although the ?optimal? configuration is not universal, we will have devised a universal patient-specific treatment planning procedure. Another intellectual merit is that this is truly an interdisciplinary research program bringing together medical professionals and engineers in an integrated and complementary approach providing a physics-based framework to approach a practical medical problem whose solution has a critical impact on a large patient population.Broader Impact: The primary impact of this project on society will be to ultimately improve the quality of life of patients with CHD that are undergoing corrective treatment using the Pavlik Harness. This study offers a practical solution to achieve effective treatment that draws from engineering expertise and modeling capabilities integrated with medical input and knowledge. Moreover, since 120,000 total hip replacements are performed annually in the United States, early detection and non-surgical correction of CHD in infants can potentially prevent enormous subsequent health-related costs. Also, graduate and undergraduate students will be immersed into a highly interdisciplinary working environment as by its very nature, the project requires students to synthesize learning from several engineering courses and physical sciences in a real-life problem of importance to society. Students are very eager to get involved in such projects that are at the interface of engineering and medicine. The bioengineering research activities of the Co-PIs have attracted a number of students including several females and Hispanic, several of whom have won science and engineering technical competitions, one on a pilot study of the very topic of this grant proposal. The College of Engineering and Computer Science (CECS) at UCF is ranked as the 3rd college of choice for Hispanics in the US by the Hispanics Business Magazine, and this project offers a unique means of recruiting such students in the field of bioengineering.