MIRALab, CUI, University of Geneva, Battelle, Building A, 7, route de Drize, 1227, Carouge, Switzerland.
Int J Comput Assist Radiol Surg. 2016 May;11(5):745-56. doi: 10.1007/s11548-015-1303-1. Epub 2015 Oct 8.
Given the crucial role of the mechanical behavior in the degenerative process of the hip joint, analyzing the contact mechanics in the articular layers during physical activities could contribute to understanding the pathology. Indeed, the development process of hip osteoarthritis generally evolves over a long time period, and therefore analyzing the mechanical behavior of the hip joint during extreme repetitive movements will be helpful to analyze degeneration causes. The aim of the study was to investigate the link between the excessive movements and the development of hip osteoarthritis.
To individualize the analysis, we used a subject-specific and noninvasive approach based on finite element analysis and magnetic resonance imaging (MRI) data. The contact pressure distribution and loading conditions on the acetabular cartilage were assessed on eleven professional dancer subjects performing a split movement. This movement is frequently practiced (repetitive) by dancers during their daily exercises. Moreover, split postures are mostly characterized by high anatomical angles with subluxation (excessive). To ensure the motion accuracy, MRI data of the subjects were acquired in neutral and split positions performed inside the MRI scanner. Based on the reconstructed bone models from the MRI data, a motion tracking approach was used to compute the transformation between the two poses. To evaluate the contact during the split movement and to quantify the role of the labrum in the hip joint mechanics, additional simulations of two daily activities (walking and stand-up) were performed. Finally, a clinical study based on morphological and radiological analysis of the subjects was performed and validated by orthopedic surgeons and radiological experts to evaluate the proposed approach.
The reconstructed split movement was characterized by high anatomical angles with a subluxation on the left hip. Consequently, strong deformations and pressures were observed during the simulation. The comparison of the simulation results of split posture and daily activities showed higher pressure and lower contact area during extreme movements. Moreover, the presence of labrum absorbed part of load and consequently decreased the predicted contact pressure and contact area on the acetabular cartilage.
The comparison of the simulation results of the split posture and daily activities, as well as the correlation between the results of the analysis on extreme movement results and the clinical analysis performed by medical experts, strongly suggests that repetitive extreme movement could lead to early hip osteoarthritis.
鉴于机械行为在髋关节退行性过程中的关键作用，分析关节层在体育活动中的接触力学有助于了解病理。事实上，髋关节骨关节炎的发展过程通常需要很长时间，因此分析髋关节在极端重复运动中的力学行为将有助于分析退化原因。本研究旨在探讨过度运动与髋关节骨关节炎发展之间的联系。
为了进行个性化分析，我们使用了一种基于有限元分析和磁共振成像（MRI）数据的个体非侵入性方法。评估了 11 名专业舞蹈演员在进行劈叉运动时髋臼软骨上的接触压力分布和载荷条件。这种运动是舞蹈演员在日常训练中经常练习的（重复性）。此外，劈叉姿势通常以高解剖角度和半脱位（过度）为特征。为了确保运动的准确性，在 MRI 扫描仪内采集了受试者处于中立和劈叉位置的 MRI 数据。基于从 MRI 数据重建的骨骼模型，使用运动跟踪方法计算了两个姿势之间的变换。为了评估劈叉运动中的接触情况，并量化半月板在髋关节力学中的作用，还进行了两种日常活动（行走和站立）的附加模拟。最后，进行了一项基于受试者形态学和影像学分析的临床研究，并由矫形外科医生和放射学专家进行验证，以评估所提出的方法。
重建的劈叉运动以左侧髋关节的高解剖角度和半脱位为特征。因此，在模拟过程中观察到强烈的变形和压力。劈叉姿势和日常活动的模拟结果比较表明，在极端运动中压力更高，接触面积更小。此外，半月板的存在吸收了部分负荷，从而降低了髋臼软骨上的预测接触压力和接触面积。
劈叉姿势和日常活动的模拟结果比较，以及对极端运动结果的分析结果与医学专家进行的临床分析之间的相关性，强烈表明重复的极端运动可能导致早期髋关节骨关节炎。
