Neck pain is a prevalent condition and clinical examination techniques are limited and unable to assess out-of-plane motion. Recent works investigating cervical kinematics during neck circumduction (NC), a dynamic 3D task, has shown the ability to discern those with and without neck pain. The purposes of this study were to establish 1) confidence and prediction intervals of head-to-torso kinematics during NC in a healthy cohort, 2) a baseline summative metric to quantify the duration and magnitude of deviations outside the prediction interval, and 3) the reliability of NC. Thirty-nine participants (25.6 ± 6.3 years, 19F/20M) without neck pain completed left and right NC. A two-way smoothing spline analysis of variance was utilized to determine the mean-fitted values and 90% confidence and prediction intervals for NC. A standardized effect size was calculated and aggregated across all axes (Delta RMSD aggregate), as a summative metric of motion quality. Confidence and prediction intervals were comparable for left and right NC and demonstrated excellent reliability. The average sum of the Delta RMSD aggregate was 2.76 ± 0.55 for left NC and 2.74 ± 0.63 for right NC. The results of this study demonstrate the feasibility of utilizing normative intervals of a NC task to assess head-to-torso kinematics.

颈部疼痛是一种普遍情况，临床检查技术有限且无法评估平面外运动。最近研究颈环转术 (NC) 期间的颈椎运动学的一项动态 3D 任务表明能够辨别有和没有颈部疼痛的人。本研究的目的是建立 1) 健康队列中 NC 期间头部到躯干运动学的置信区间和预测区间，2) 用于量化预测区间外偏差的持续时间和幅度的基线总结性指标，以及 3) NC的可靠性。39 名参与者（25.6 ± 6.3 岁，19F/20M）没有颈部疼痛，完成了左右 NC。利用双向平滑样条方差分析来确定 NC 的平均拟合值和 90% 置信区间和预测区间。计算并汇总了所有轴的标准化效果大小（Delta RMSD 汇总），作为运动质量的总结指标。左右 NC 的置信区间和预测区间相当，并表现出极好的可靠性。Delta RMSD 聚合的平均总和对于左侧 NC 为 2.76 ± 0.55，对于右侧 NC 为 2.74 ± 0.63。这项研究的结果证明了利用 NC 任务的规范间隔来评估头到躯干运动学的可行性。