Reliability and validity of rasterstereography measurement for spinal alignment in healthy subjects

Abstract

Objective: The Back Mapper is one type of Rasterstereography and it can be used in the clinic without radiation exposure. The purpose of our study was to prove the reliability and validity of the Back Mapper and to compare it with the Spinal Mouse, which is an assessment tool for spinal curvatures using a wheeled mouse, and the Cobb angle by X-ray. Design: Cross-sectional study. Methods: Twenty healthy adults participated in the test to investigate for the inter-rater reliability, intra-rater reliability, and concurrent validity. The tests were performed with assessment devices for scoliosis such as the Back Mapper, Spinal Mouse and Cobb's angle. Data was analyzed by an intraclass correlation coefficient (ICC) value and a standard error of measurement for reliability and correlation analysis for validity. Results: Intra-rater reliability of the Back Mapper was good (Cronbach's α=0.821-0.984, ICC=0.696-0.969) except for assessing the lordotic angle. Inter-rater reliability was good (Cronbach's α=0.870-0.958, ICC=0.770-0.919) in assessment for trunk imbalance, rotation of scapulae, thoracic angle, lumbar angle, and kyphotic angle. The kyphotic angle in the Spinal Mouse had a significant correlation icompared with the Back Mapper (r=0.510, p<0.05), and the Cobb's angle from an X-ray had a significant correlation with trunk inclination (r=0.532, p<0.05). Conclusions: These findings provide good intra-reliability of the Back Mapper in healthy subjects, but the Back Mapper requires more experienced practice to have good inter-reliability. Also, the variables of the Back Mapper does not seem as appropriate compared with the Cobb angle by X-ray.

Standard reference values of the upper body posture in healthy middle-aged female adults in Germany

“…Under the premise of an experienced user of the BodyMapper good inter-class correlations can be demonstrated (Table 1 ). Additionally, Yi et al 20 show appropriate intra- and inter-rater-reliabilies. Additional limitations of this study are described and discussed in the preliminary method paper 25 , 26 .…”

“…The system error is specified as < 1 mm (manufacturer information) and the reproducibility is limited by the calculations of the upper body posture defined by markers directly on the skin (< 0.5 mm). Yi et al 20 have calculated the intra- and inter-reliabilies of this measurement system and described it as good in both cases. Furthermore, they also proved the correlation between the Cobb angle via X-ray radiography and the bodymapper of the lordosis and kyphosis angles.…”

“…Video raster stereography is a radiation-free and touch-free method to depict the back surface in three dimensions with a high (intra- and inter-day) reliability and reproducibility 20 , 21 ; with the use of given anatomical landmarks its accuracy increases 22 . Furthermore, the brief procedure simplifies the survey and makes it more accessible for participants 23 , 24 .…”

The study of trunk and pelvic movement on mediolateral ramps of various ramp angles during one-legged standing

“…Pelvic torsion angle represented the degree of anterior and posterior tilt of the pelvis. For the rotation of the pelvis on the horizontal plane, a positive value indicated rotation to right side, and a negative value indicated rotation to left side ( Cho, 2016 ; Yi et al, 2016 ).…”

“…Marking the position of the feet ensured the reproducibility of the foot positions. The examiner manually placed reflective markers on C7, on both sides of the scapular inferior angle, on the bilateral posterior superior iliac spine, and on the center of the sacrum, totaling six reflective markers placed on each subject ( Yi et al, 2016 ). Prior to measurement, each participant was instructed verbally and visually how to perform a one-leg stance on the medial and lateral ramps, and each participant was allowed three minutes of practice time to become familiar with the ramps.…”