Validity and reliability of POM-Checker in measuring shoulder range of motion: Protocol for a single center comparative study.

INTRODUCTION: Assessments of the range of motion (ROM) in human joints have been widely used to evaluate the joint condition. Although maker based motion capture system is the most popular and practical method in the clinical field, there have been limitations such as the relatively long time required in procedure or influence of attached markers on natural movement. Recently, markerless motion capture systems have been actively developed due to their relatively lower cost and convenience for installation. The POM-Checker (Team Elysium Inc., Seoul, Rep of Korea), a markerless motion capture system, was developed with new algorithms to assess the ROM in human joints. However, the measure of the POM-Checker has not been compared with a golden-standard device in evaluating the ROM in the human joints. So we developed a protocol to evaluate the validation and reliability of the POM-Checker in measuring the shoulder ROM. This study will also provide a standard procedure to measure the shoulder ROM with the POM-Checker and 3D motion analysis system simultaneously.

METHODS/DESIGN: This protocol is for a single institution comparative study to evaluate the validity and reliability of POM-Checker. Six participants will be recruited. We will measure the angles of shoulder abduction and flexion with POM-Checker and 3D motion analysis system simultaneously. The primary outcome is the angles of shoulder abduction and flexion.

DISCUSSION: This will be the first study to analyze the validity and reliability of POM-Checker in measuring shoulder ROM. Although the sample size of this study is small, it may not influence on the results conclusively, because the measures are very precise numerical angles. Furthermore, the angles of shoulder movements will be measured with both devices simultaneously.

CONCLUSION: The results of the study will be helpful to find out the validity and reliability of a new developed ROM measure device, POM-Checker, by comparison with a golden standard system, 3D motion capture system, in measuring the shoulder ROM. It will also contribute to use of the POM-Checker in measuring the ROMs in many human joints.