Measurement of sacroiliac joint dysfunction: A multicenter intertester reliability study

Abstract

Background and Purpose. Previous research suggests that visual estimates of sacroiliac joint (SIJ) alignment are unreliable. The purpose of this study was to determine whether handheld calipers and an inclinometer could be used to obtain reliable measurements of SIJ alignment in subjects suspected of having SIJ dysfunction. Subjects. Seventy-three subjects, evaluated at 1 of 5 outpatient clinics, participated in the study. Methods. A total of 23 therapists, randomly paired for each subject, served as examiners. The angle of inclination of each innominate was measured while the subject was standing. The position of the innominates relative to each other was then derived. An intraclass correlation coefficient (ICC), the standard error of measurement (SEM), and a kappa coefficient were calculated to examine the reliability of the derived measurements. Results. The ICC was .27, the SEM was 5.4 degrees, and the kappa value was .18. Conclusion and Discussion. Measurements of SIJ alignment were unreliable. Therapists should consider procedures other than those that assess SIJ alignment when evaluating the SIJ.