Marker-Based Method for Analyzing the Three-Dimensional Upper Body Kinematics of Violinists: Reproducibility

Area of Science:

• Biomechanics
• Kinesiology
• Musculoskeletal Research

Background:

• A novel marker-based method was proposed for analyzing 3D upper-body kinematics in high string players.
• This method objectively evaluates motor strategies, distinguishing scapulothoracic (ST) and glenohumeral (GH) joints while minimizing artifacts.
• Reproducibility is critical for clinical applications of kinematic measurements.

Purpose of the Study:

• To assess the reproducibility of a novel marker-based method for analyzing upper-body kinematics in violinists.
• To evaluate the reliability and repeatability of kinematic measurements obtained using this method.

Main Methods:

• A healthy professional violinist participated in nine bowing trials across three laboratory sessions.
• Examiners (two) conducted trials, applying a biomechanical model to motion capture data of the upper body and limbs.
• Reproducibility was assessed via inter- and intra-tester, inter-session, and intra-subject measurement errors for joint kinematics.

Main Results:

• Intra- and inter-tester errors were small, generally less than 3°, indicating good reliability.
• Inter-session and intra-subject repeatability errors were larger, mostly under 5°.
• Small measurement errors were observed, supporting the method's reproducibility.

Conclusions:

• The novel marker-based method demonstrated good reproducibility for a healthy violinist.
• The findings suggest the method is a reliable tool for quantifying upper-body movements in violin playing.
• This method shows potential for clinical application across various subjects, examiners, and settings.