Use of the Zebris Ultrasonic Three-Dimensional Motion Analysis System to Evaluate Range of Motion of the Cervical Spine in 61 Healthy Adults

BACKGROUND The Zebris ultrasonic three-dimensional motion analysis system is an established and validated method used to measure flexion, extension, range of lateral bending, and range of axial rotation in the cervical spine. This study aimed to assess the Zebris ultrasonic three-dimensional motion analysis system to evaluate the range of motion of the cervical spine in 61 healthy adults. MATERIAL AND METHODS Sixty-one healthy individuals took part in the study. Each participant was examined twice, 2 weeks apart, by 2 independent raters. The cervical spine range of motion was measured in the sitting position, in 3 planes of motion. Measurements were performed using the Zebris ultrasound-based three-dimensional motion analysis system. Intra-rater agreement (reproducibility) was assessed by comparing the results of the 2 measurements performed by the same rater, while inter-rater agreement was evaluated by comparing the measurements of the 2 independent raters. RESULTS Intra-rater agreement showed Intraclass Correlation Coefficient (ICC) values ranging from 0.92 to 0.96 across all planes of motion, indicating high consistency of measurements over time. Inter-rater agreement showed ICC values ranging from 0.91 to 0.95, confirming high agreement between the 2 independent raters. CONCLUSIONS The study demonstrates that the Zebris ultrasonic three-dimensional motion analysis system presents excellent inter-rater and intra-rater agreement in measurements of cervical range of motion, in healthy Polish young adults. These findings support its use in clinical practice for diagnosing cervical spine mobility disorders, planning therapeutic interventions, and monitoring treatment outcomes.