Reliability and validity of measuring shoulder joint flexion using digital and standard goniometric methods

Abstract

Based on the literature review and clinical experiences, it can be concluded that measuring the amplitude of movement is one of the fundamental kinesiometric methods used in assessing joint functionality. The aim of this study was to examine the reliability and validity of measuring the shoulder joint's range of motion using the digital system KEMTAI compared to a goniometer with arms. This non-experimental observation was conducted on 40 participants whose flexion range in the shoulder joint was measured using both the goniometer with arms and the KEMTAI software system, which utilizes the examiner's mobile phone camera. The results indicated that the lowest mean value was obtained during the first measurement session (M1 = 154.68), while the highest was during the third session (M2 = 156.53). When using the KEMTAI software, the variability of mean values for the total tested population was significantly higher than when using the goniometer with arms. The results suggest that the KEMTAI software/system is reliable when comparing the average results of three measurements. Based on these findings, it is concluded that three experienced measurers demonstrated high reliability in measuring the shoulder joint's flexion range using the goniometer with arms. Despite the identified differences between the measurement results obtained using these two methods, it is considered that the KEMTAI software/system is applicable in practical work.