Musculoskeletal and Finite Element Modeling of Femoroacetabular Impingement

描述(由申请人提供)：髋臼撞击(FAI)是一种髋关节间隙减少，导致髋关节疼痛，并可能使髋关节易患骨关节炎(OA)。改变的生物力学被认为是骨性关节炎的关键始动因素。FAI患者通常表现为软骨唇损伤和活动范围受限，这表明FAI改变了软骨/唇接触力学和髋关节运动学。最近的研究表明，FAI还可能导致肌肉激活和力量的初级或适应性变化。以前的临床和基础生物力学研究都未能阐明FAI、生物力学改变和OA之间的联系，原因是操作方法过于简单或测试设备不准确。我们的长期目标是通过量化髋关节生物力学来改善FAI的诊断和治疗。为了支持这一目标，我们建议进行一项R21水平的研究，以证明使用实验和计算相结合的方案来量化人类髋关节的关节运动学、肌肉力量/激活以及软骨/唇骨接触力学的可行性。我们将结合使用双荧光透视和基于相机的标记跟踪来量化日常生活活动中的肢体运动学。肌肉骨骼(MS)模型将估计肌力/激活，而有限元(FE)模型将预测软骨唇力学。在过去，我们的MS模型假定髋关节中心处于静止状态并预定义肌肉附着点，而我们的有限元模型假定文献中的边界和载荷条件。在本R21中，我们将比较特定于主题的模型与假设预定义或基于文献的输入的模型之间的MS模型(目标1)和FE模型(目标2)预测。在确定了所需的模型复杂性水平并对来自R21的试点数据进行了功率分析后，我们将寻求R01级别的资金，以扩展我们的计算和实验方案，以进一步研究FAI的生物力学。

DESCRIPTION (provided by applicant): Femoroacetabular impingement (FAI) is a reduction in hip joint clearance that causes hip pain and may predispose the hip joint to osteoarthritis (OA). Altered biomechanics are considered the key initiator of OA. Patients with FAI often present with chondrolabral damage and restrictions in range of motion, suggesting that FAI alters cartilage/labrum contact mechanics and hip kinematics. Recent studies suggest that FAI may also cause primary or adaptive changes to muscle activation and force. Previous clinical and basic biomechanics studies have failed to elucidate the link between FAI, altered biomechanics and OA due to oversimplified approaches or inaccurate testing equipment. Our long term goal is to improve the diagnosis and treatment of FAI by quantifying hip biomechanics. To support this goal, we propose a R21-level research study to demonstrate the feasibility of using a combined experimental and computational protocol to quantify joint kinematics, muscle forces/activations, and cartilage/labrum contact mechanics in the human hip. We will use a combination of dual fluoroscopy and camera-based marker tracking to quantify lower limb kinematics during activities of daily living. Musculoskeletal (MS) models will estimate muscle forces/activations and finite element (FE) models will predict chondrolabral mechanics. In the past, our MS models assumed a static hip joint center and pre-defined muscle attachments and our FE models assumed boundary and loading conditions from the literature. In this R21, we will compare MS model (Aim 1) and FE model (Aim 2) predictions between models that are subject-specific with those that assume pre-defined or literature-based inputs. After determining the required level of model complexity and after conducting power analyses with the pilot data from this R21, we will pursue R01 level funding extending our computational and experimental protocols to further investigate the biomechanics of FAI.