Agreement between a 3D camera system and an inertial measurement unit for assessing the range of motion, head repositioning accuracy and quality of movement during neck and head movements

Abstract

Purpose

Altered head range of motion (RoM) and head repositioning accuracy (HRA) are commonly reported in neck pain. However, the quality of motion (QoM) is currently not easy to assess clinically. This study investigated the agreement of head rotation recordings using a 3D camera system compared to a commercially available inertial measurement unit (MOTI).

Materials and methods

Thirty participants, mean age 26.5 years old (SD 4.4), partook in this study. Participants wore a Headband with MOTI and markers for 3D motion capture analysis during head rotations. The two systems recorded active head RoM in rotation, HRA, and QoM. Agreement of RoM, HRA and QoM data was compared between the two systems using Interclass correlation coefficients (ICC; 2.1) and Bland-Altman plots.

Results

Good to excellent agreement between the two systems was seen for RoM (ICC: 0.998), HRA (0.75–0.88) and QoM (ICC: 0.911–0.913). The Bland-Altman plots revealed a systemic offset where the MOTI device measured higher values for RoM (mean bias: −0.56 ± 0.65°), HRA (mean bias: 0.48 ± 0.76°) and QoM (mean bias: −16.9 ± 51.6 A.U.).

Conclusion

The present study found that the MOTI device can accurately measure RoM, HRA and QoM during head rotation. MOTI may be preferred over a 3D camera system for clinical use.

Keywords:

• Range of motion
• motion capture
• kinematics
• head movements
• neck pain

Disclosure statement

Steffan Wittrup McPhee Christensen & Thorvaldur Skuli Palsson are co-founders of MOTI. They did not participate in data collection or statistical analysis.

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.