The Validity and Inter-Rater Reliability of a Video-Based Posture-Matching Tool to Estimate Cumulative Loads on the Lower Back.

BACKGROUND

Low back pain (LBP) is known as one of the most common work-related musculoskeletal disorders. Spinal cumulative loads () during manual material handling (MMH) tasks are the main risk factors for LBP. However, there is no valid and reliable quantitative lifting analysis tool available for quantifying among Iranian workers performing MMH tasks.

OBJECTIVE

This study aimed to investigate the validity and inter-rater reliability of a posture-matching load assessment tool (PLAT) for estimating the L5-S1 static cumulative compression () and shear () loads based on predictive regression equations.

MATERIAL AND METHODS

This experimental study was conducted among six participants performing four lifting tasks, each comprised of five trials during which their posture was recorded via a motion capture (Vicon) and simultaneously a three-camera system located at three different angles (0°, 45°, and 90°) to the sagittal plane.

RESULTS

There were no significant differences between the two estimated by PLAT from the three-camera system and the gold-standard Vicon. In addition, ten raters estimated of the tasks using PLAT in three sessions. The calculated intra-class correlation coefficients for the estimated within each task revealed excellent inter-rater reliability (> 0.75), except for in the first and third tasks, which were good (0.6 to 0.75).

CONCLUSION

The proposed posture-matching approach provides a valid and reliable ergonomic assessment tool suitable for assessing spinal during various lifting activities.