Accuracy and reliability study of EOSTM in the evaluation of adult scoliosis

QIN Le; DU Lian-jun; YAN Fu-hua

doi:10.3969/j.issn.2095-252X.2016.08.003

Abstract：Objective To study the accuracy and reliability of EOSTM imaging system in the evaluation of adult scoliosis.Methods Between September 2015 and January 2016, EOS images from 41 adult scolisis patients ( 5 males, 36 females, mean age 64.6-year-old ) were collected for the study. SterEOS software was used to do 3 D reconstruction of the spine to obtain a set of measurements, including Cobb’s angle, apical vertebral rotation, T1-12 kyphosis, T4-12 kyphosis, L1-5 lordosis, L1 - S1 lordosis, pelvic incidence, sacral slope, sagittal pelvic tilt, lateral pelvic tilt and pelvis axial rotation. Two radiologists were blinded to each other to conduct 3 D software generated measurements from an EOS imaging system. They also scored the conformance of 3 D model and images. Intra-class correlation coefficients were compared to evaluate inter-observer variability. Patients were also classified to 3 groups according to Cobb’s angle to analyze conformance.Results Intra-class correlation coefifcients were 0.990, 0.911, 0.971, 0.972 and 0.949 (P < 0.01 ) for Cobb’s angle, apical vertebral rotation, T4-12 kyphosis, L1-5 lordosis and L1 - S1 lordosis, respectively. Only poor intra-class correlation coefifcient: 0.194 (P = 0.104 ) for T1-12 kyphosis. Intra-class correlation coefifcients were 0.846, 0.885, 0.914, 0.987 and 0.779 (P < 0.01 ) for pelvic incidence, sacral slope, sagittal pelvic tilt, lateral pelvic tilt and pelvis axial rotation. Conformation scores were statistically different among patients in 3 groups of different Cobb’s angles (F = 4.721,P = 0.015 ).Conclusions EOS imaging and sterEOS 3 D reconstruction create accurate and reliable measurements in adult scoliosis, providing a novel method for radiologists and orthopedists to improve the assessment of scoliosis.