Abstract：
Shoulder complex stability can be estimated in vivo through the analysis of helical axes (HAs) dispersion during upper limb movements. The study aimed at investigating test-retest reliability of shoulder HAs dispersion parameters during upper limb tasks. Twenty healthy volunteers performed 2 intransitive (shoulder flexion and rotation) and one transitive (combing) tasks with the dominant and nondominant upper limbs during 2 recording sessions at 1-week distance. Kinematics was detected through an optoelectronic system. Mean distance and mean angle (MA) were adopted as HAs dispersion indexes. Reliability was excellent for mean distance (intraclass correlation coefficient [ICC]: .91) and MA (ICC: .92) during dominant flexion, and good for MA (ICC: .90) during nondominant flexion. Moderate reliability was found for HAs parameters during rotation (ICCs from .70 to .59), except for MA during dominant rotation where reliability was poor. Reliability was good for mean distance (ICC: .83) and moderate for MA (ICC: .67) during the dominant combing task, whereas no reliability was found during the nondominant combing task. HAs dispersion parameters revealed high reliability during simple intransitive tasks with the dominant limb. Reliability decreased with the increase in task complexity due to the increase in movement variability. HAs dispersion technique could be used to assess shoulder complex stability in patients after rehabilitation or surgery.
摘要：
通过分析上肢运动过程中的螺旋轴（HA）色散，可以在体内估算肩部复合物的稳定性。该研究旨在调查上肢任务期间肩关节HAs色散参数的重测可靠性。20名健康志愿者在1周的距离内进行了2次录音，对优势和非优势上肢进行了2次无及物（肩屈曲和旋转）和1次及物（梳理）任务。通过光电系统检测运动学。采用平均距离和平均角度（MA）作为HAs色散指标。在优势屈曲期间，平均距离（组内相关系数[ICC]：.91）和MA（ICC：.92）的可靠性非常好，在非显性屈曲期间对MA（ICC：.90）有益。在旋转过程中发现HA参数的中等可靠性(ICC从.70到.59)，除了主要轮换期间的MA，可靠性较差。在主要的梳理任务中，平均距离（ICC：.83）的可靠性良好，MA（ICC：.67）的可靠性中等，而在非显性梳理任务中没有发现可靠性。HAs色散参数在对优势肢体进行简单的无及物任务时显示出高可靠性。由于运动可变性的增加，可靠性随着任务复杂性的增加而降低。HAs弥散技术可用于评估康复或手术后患者的肩关节稳定性。
