Stiffness, viscosity, and upper-limb inertia about the glenohumeral abduction axis.
Stiffness, viscosity, and upper-limb inertia about the glenohumeral abduction axis.
复制标题
围绕盂肱外展轴的刚度、粘度和上肢惯性。
DOI：
10.1002/jor.1100180114
复制
发表时间：
2000
期刊：
影响因子：
--
通讯作者：
Hendrix,RW
中科院分区：
文献类型：
--
作者：
Zhang,LQ;Portland,GH;Wang,G;DiRaimondo,CA;Nuber,GW;Bowen,MK;Hendrix,RW
为了评估肩部的动态特性并了解它们如何受中枢神经系统控制，在7名健康受试者的不同肌肉收缩水平下对盂肱关节刚度和粘度以及上肢惯性进行了量化。通过一个石膏附件，上肢被一个计算机控制的振动器以精确的模式扰动，以显示关节的动态特性。记录的关节位置和扭矩用于估计关节刚度和粘度以及上肢惯性。随着适度的肌肉收缩，硬度和粘度增加了几倍。更硬的肩关节与更强的肌肉收缩相关联，使肩膀更稳定，并保护它在繁重的任务中免受潜在的伤害。关节粘性，特别是与更剧烈收缩相关的更强的粘性阻尼，使肩部运动平稳并稳定关节。从控制的角度来看，盂肱关节对中枢神经系统的反应更快，肌肉收缩增加，这在繁重的任务中是有用的。另一方面，中枢神经系统同时控制刚度和粘性，因此它只处理关节在不同收缩水平上几乎恒定的阻尼比，这大大简化了它的任务。这种方法量化的动态和静态性能的肩膀下的各种水平的收缩比手动测试更准确和完整，它可以被用来评估这些属性的变化所造成的肌肉骨骼损伤和手术治疗。
To evaluate the dynamic properties of the shoulder and understand how they are controlled by the central nervous system, glenohumeral‐joint stiffness and viscosity and upper‐limb inertia were quantified under various levels of muscle contraction in seven healthy human subjects. Through a cast attachment, the upper limb was perturbed in a precise pattern by a computer‐controlled servomotor to manifest the dynamic properties of the joint. The recorded joint position and torque were used to estimate joint stiffness and viscosity and upper‐limb inertia. With moderate muscle contraction, the stiffness and viscosity increased several fold. A stiffer shoulder joint associated with stronger muscle contraction made the shoulder more stable and protected it from potential injuries during strenuous tasks. Joint viscosity, especially the stronger viscous damping associated with more strenuous contraction, smoothed shoulder movement and stabilized the joint. From the control viewpoint, the glenohumeral joint responded to the central nervous system more quickly with increasing muscle contraction, which was useful during strenuous tasks. On the other hand, the central nervous system controlled stiffness and viscosity synchronously so that it dealt with only a nearly constant damping ratio of the joint over various levels of contraction, which simplified its task substantially. This approach quantified the dynamic and static properties of the shoulder under various levels of contraction more accurately and completely than a manual test, and it can potentially be used to evaluate changes in these properties caused by musculoskeletal injuries and their surgical treatments.