Institute for Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds, UK; NIHR Leeds Biomedical Research Centre, Leeds, UK.
Institute for Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds, UK; NIHR Leeds Biomedical Research Centre, Leeds, UK; Arthritis Research UK Experimental Arthritis Centre, Leeds, UK.
J Biomech. 2019 Apr 18;87:19-27. doi: 10.1016/j.jbiomech.2019.02.002. Epub 2019 Feb 16.
To examine functional differences in total hip replacement patients (THR) when stratified either by age or by functional ability as defined by self-selected walking speed. THR patients and a control group underwent three-dimensional motion analysis under self-selected normal and fast walking conditions. Patients were stratified into five age groups for comparison with existing literature. The THR cohort was also stratified into three functional groups determined by their self-selected gait speed (low function <1SD of total cohort's mean walking speed; high function >1SD; normal function within 1SD). Hip kinematics, ground reaction forces, joint moments and joint powers in all three planes (x-y-z) were analysed. 137 THR and 27 healthy control patients participated. When stratified by age, during normal walking the youngest two age groups walked quicker than the oldest two groups (p < 0.0001) but between-group differences were not consistent across age strata. The differences were diminished under the fast walking condition. When stratified by function, under normal walking conditions, the low function and normal function THR groups had a reduced extension angle (mean = 1.75°, SD = ±7.75, 1.26° ± 7.42, respectively) compared to the control group (-6.07° ± 6.43; p < 0.0001). The low function group had a reduced sagittal plane hip power (0.75 W/kg ± 0.24), reduced flexor (0.60 Nm/kg ± 0.85) and extensor moment (0.51 Nm/kg ± 0.17) compared to controls (p < 0.0001). These differences persisted under the fast walking condition. There were systematic differences between patients when stratified by function, in both walking conditions. Age-related differences were less systematic. Stratifying by biomechanical factors such as gait speed, rather than age, might be more robust for investigating functional differences.
为了研究全髋关节置换患者（THR）在按年龄或自我选择的行走速度定义的功能能力分层时的功能差异，THR 患者和对照组在自我选择的正常和快速行走条件下接受了三维运动分析。患者被分为五个年龄组与现有文献进行比较。THR 队列还根据自我选择的步态速度分为三个功能组（低功能<总队列平均行走速度的 1SD；高功能>1SD；正常功能在 1SD 内）。分析了所有三个平面（x-y-z）的髋关节运动学、地面反作用力、关节力矩和关节功率。共有 137 名 THR 和 27 名健康对照组患者参与了研究。按年龄分层时，在正常行走时，最年轻的两个年龄组比最年长的两个年龄组行走速度更快（p<0.0001），但不同年龄组之间的差异并不一致。在快速行走条件下，差异减小。按功能分层时，在正常行走条件下，低功能和正常功能 THR 组的伸展角度减小（平均值=1.75°，标准差=±7.75，分别为 1.26°±7.42）与对照组相比（-6.07°±6.43；p<0.0001）。低功能组在矢状面髋关节功率（0.75 W/kg±0.24）、屈肌（0.60 Nm/kg±0.85）和伸肌（0.51 Nm/kg±0.17）方面均低于对照组（p<0.0001）。在快速行走条件下，这些差异仍然存在。在两种行走条件下，按功能分层时，患者之间存在系统差异。与年龄相关的差异不那么系统。按步态速度等生物力学因素分层，而不是按年龄分层，可能更有助于研究功能差异。
