Temporiti Federico, Cescon Corrado, Adamo Paola, Natali Fabrizio, Barbero Marco, De Capitani Francesca, Gatti Roberto
Physiotherapy Unit, Humanitas Clinical and Research Center - IRCCS, Rozzano, Milan, Italy; Humanitas University, Department of Biomedical Sciences, Pieve Emanuele, Milan, Italy.
Rehabilitation Research Laboratory, Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Manno, Switzerland.
J Biomech. 2020 Aug 26;109:109944. doi: 10.1016/j.jbiomech.2020.109944. Epub 2020 Jul 15.
Knee joint rotation center displacement can be estimated in vivo through the analysis of helical axis (HAs) dispersion. HAs can be analyzed during walking, providing information on joint stability. The study aim was to describe knee HAs dispersion during walking in dominant and non-dominant legs of young and elderly healthy subjects. Twenty young (YG: age 23.3 ± 2.4 years) and twenty elderly (EG: age 69.3 ± 4.6 years) healthy subjects were asked to walk on a treadmill at a self-selected speed with reflective markers placed bilaterally on thighs and shanks to detect HAs dispersion and knee kinematics with an optoelectronic system. HAs dispersion was described during the following four phases of gait cycle: (1) flexion from 95% of the previous gait cycle to 10% of the subsequent gait cycle, (2) extension from 10% to 40%, (3) flexion from 40% to 75% and (4) extension from 75% to 95% of the gait cycle. Mean Distance (MD) and Mean Angle (MA) were used as HAs dispersion indexes during each gait phase. Participants showed greater MD and MA in sagittal and frontal planes during the first and second phases. EG revealed higher MD (p = 0.001) and MA (p < 0.001) during the first phase and higher MA (p = 0.001) during the fourth phase in both dominant and non-dominant legs on the sagittal plane. HAs dispersion could be related to the amount of forces acting on knee (first two phases) and knee degeneration (elderly). These results may be used as reference data in further studies on HAs dispersion in presence of knee pathologies or after knee surgery or rehabilitation.
膝关节旋转中心位移可通过螺旋轴（HA）离散度分析在体内进行估计。在行走过程中可对HA进行分析，从而提供有关关节稳定性的信息。本研究的目的是描述年轻和老年健康受试者优势腿和非优势腿在行走过程中的膝关节HA离散度。20名年轻（YG组：年龄23.3±2.4岁）和20名老年（EG组：年龄69.3±4.6岁）健康受试者被要求在跑步机上以自选速度行走，双侧大腿和小腿放置反光标记，通过光电系统检测HA离散度和膝关节运动学。在步态周期的以下四个阶段描述HA离散度：（1）从前一个步态周期的95%到后一个步态周期的10%的屈曲阶段，（2）从10%到40%的伸展阶段，（3）从40%到75%的屈曲阶段，以及（4）从75%到95%的伸展阶段。在每个步态阶段，平均距离（MD）和平均角度（MA）被用作HA离散度指标。参与者在第一和第二阶段在矢状面和额状面显示出更大的MD和MA。EG组在矢状面的优势腿和非优势腿在第一阶段均显示出更高的MD（p = 0.001）和MA（p < 0.001），在第四阶段显示出更高的MA（p = 0.001）。HA离散度可能与作用在膝关节上的力的大小（前两个阶段）和膝关节退变（老年人）有关。这些结果可作为进一步研究膝关节病变、膝关节手术或康复后HA离散度的参考数据。
