Intra- and inter-rater reliability of angle assessment for righting reaction from a tilted sitting position in healthy participants

[Purpose] Lateral balance and the righting reaction are related to trunk function and many activities of daily living. However, there are no studies evaluating the assessment of the righting reaction while ensuring safety. This study aimed to clarify the reliability of assessments for the righting reaction from a tilted sitting position in healthy participants. [Participants and Methods] The participants of this study included 28 healthy young adults. Before the start of the study, markers were attached to the participants for data collection. Participants were asked to sit on a vertical board, tilted 10 degrees, and were asked to perform the righting reaction. This test was repeated four times on each side. The actions were recorded with a video camera, and two analysts used the Image J software to calculate the angles of the righting reaction of the neck, trunk, and left and right lower legs. [Results] High reliability was obtained regardless of the tilt direction and site of righting reaction. In addition, no adverse events occurred. [Conclusion] It was possible to evaluate the righting reaction while ensuring safety, and reproducibility was confirmed.