Reliability and Validity of Angle of Trunk Rotation Measurement Using Smartphone and 3D Printing Technology in Scoliosis

ABSTRACT

Purpose@#The purpose of this study was to compare and analyze the method of measuring the angle of the trunk rotation using a smartphone with 3D smartphone holder compared to a scoliometer, which is a measuring tool used as a method for diagnosing scoliosis in scoliosis patients. @*Methods@#Angle of trunk rotation was measured in 21 subjects diagnosed with scoliosis. scoliometer measurement method, a smartphone measurement method with a 3D smartphone holder, a smartphone blind measurement method with a 3D smartphone holder, a smartphone measurement method without a smartphone holder, a smartphone blind measurement method without a smartphone holder, and a total of five measurement methods were repeated three times for comparison and analysis. @*Results@#The smartphone measurement method with a 3D smartphone holder has excellent intra-rater reliability of angle of trunk rotation (Rater A; ICC3, 2 ≥ 0.993, Rater B; ICC3, 2 ≥ 0.992). The smartphone blind measurement method with a 3D smartphone holder has excellent inter-rater reliability of angle of trunk rotation (ICC2, 2 ≥ 0.968). The scoliometer measurement method had the highest validity (r = 0.976) with the smartphone measurement method with a 3D smartphone holder, and the blind measurement method without a smartphone holder had the lowest validity (r = 0.886). @*Conclusion@#These findings, the angle of trunk rotation measured by the smartphone measurement method with a 3D smartphone holder in scoliosis patients showed high reliability and validity compared to the scoliometer measurement method.