Abstract：
There is a lack of data unaffected by soft tissue artifact describing bilateral symmetry and sex differences in hip kinematics in asymptomatic individuals during activities of daily living. This study aimed to identify sex-based differences and to quantify bilateral symmetry in continuous hip kinematics during walking and bodyweight squatting using biplane radiography. Twenty-four asymptomatic young adults (13 women, 11 men; age: 21.9 ± 2.2 years) performed treadmill walking and squatting while synchronized biplane radiographs of the hip were collected at 50 frames/s. Pelvis and proximal femur bone tissue were segmented from CT images and reconstructed into subject-specific 3D bone models. Femoroacetabular kinematics were determined using a validated volumetric model-based tracking technique that matched digitally reconstructed radiographs generated from the CT-based bone models to the biplane radiographs. Symmetry was calculated as the average absolute side-to-side difference (SSD) in kinematic waveforms for each participant. Sex-based and phase-based (eccentric vs. concentric squatting) kinematic variations were assessed using linear mixed model analysis. Women were 0.2 mm more anteriorly translated and 0.1 mm more inferiorly translated than men across the gait cycle (both p < 0.04), but no sex-based or phase-based kinematic differences during squatting were identified. The maximum SSD across all movements was up to 18.6° (internal-external rotation) and 1.0 mm (superior-inferior translation), respectively. Asymmetry in internal rotation, superior translation, and medial translation was greater during squatting than during walking (all p < 0.002). This study provides a reference dataset of healthy young adults for evaluating hip kinematics and symmetry in symptomatic cohorts or in individuals undergoing surgery or rehabilitation.
摘要：
缺乏不受软组织伪影影响的数据，这些数据描述了无症状个体在日常生活活动期间髋关节运动学的双侧对称性和性别差异。这项研究旨在确定基于性别的差异，并使用双平面X线摄影量化步行和体重下蹲过程中连续髋关节运动学的双侧对称性。24名无症状的年轻成年人(13名妇女，11名男性；年龄：21.9±2.2岁）进行跑步机行走和下蹲，同时以50帧/s的速度收集髋关节的同步双平面X射线照片。从CT图像分割骨盆和股骨近端骨组织，并重建为受试者特定的3D骨模型。使用经过验证的基于体积模型的跟踪技术确定股骨髋臼运动学，该技术将从基于CT的骨骼模型生成的数字重建X射线照片与双平面X射线照片相匹配。对称性计算为每个参与者的运动学波形的平均绝对左右差(SSD)。基于性别和基于阶段（偏心与同心蹲）使用线性混合模型分析评估了运动学变化。在整个步态周期中，女性比男性向前平移0.2mm，向下平移0.1mm（均p<0.04），但是没有发现下蹲过程中基于性别或基于相位的运动学差异。所有运动的最大SSD高达18.6°（内外旋转）和1.0mm（上下平移），分别。内部旋转不对称，优越的翻译，蹲时的内侧平移大于步行时的内侧平移（所有p<0.002）。这项研究提供了健康年轻人的参考数据集，用于评估有症状的队列或接受手术或康复的个体的髋关节运动学和对称性。
