Assessment of HR-QOL, GS-align, BMD, SMI, and BMES

For the evaluation of QOL, medical Outcome Study Short-Form36-Health Survey Version 2 for Japanese (SF-36v2) was used [8].

To evaluate GS-Align, the whole spine radiograms were taken in anteroposterior and lateral directions in a naturally standing position with the arms resting on the chest. The effective dose is estimated to 4.60mSv in our institute. As parametres of GS-Align, CL, TK, LL, SS, PI, PT, PI-LL, and SVA were measured by 3 radiographers certified by the Japan Association of Radiological Technologist, and the mean value of them was used for the evaluation.

BMI (body weight / body height squared, kg/m²) was calculated. BMD of the hip in anteroposterior direction (g/cm²) and SMI (arm muscle mass + leg muscle mass/body height squared, kg/m²) were calculated using Dual Energy X-ray Absorptiometry (Hologic DISCOVERY A, Bedford, MA). The effective dose is estimated to 0.002mSv in our institute.

BMES was determined based on a method by Limburg et al [9]. A strain-gauge dynamotor (Biotec, Akita City, Japan) was attached to the frame, and the maximum extension force was measured at the T4 to T7 level in the supine position with the hips and knees extended, and the arms resting at the sides in bed. The BMES test was done under supervision of skilled physical therapists.