On the reliability and accuracy of measuring the angles, utilizing two methods of manual and AutoCAD analysi

Measuring the joint angles is used to assess joint position sense (JPS). The aim of this study was to introduce a fast, less expensive, objective and simple method of measurement.In this study, the accuracy and reliability of a system, comprising digital photography, nonreflective markers and AutoCAD analysis (or manual analysis) were evaluated. For this purpose, the digital photos were taken from 9 angles of a standard goniometer whereas 4 square markers were been attached on its arms. The goniometer was placed at two locations on a calibration board. The angles were measured by using AutoCAD software via the markers, corners. Furthermore, the markers were recorded at 72 angles of the knee joint positions in 24 healthy subjects.The knee angles were measured by 3 investigators and by using transparnt sheets and goniometry.ICC was 1 for each location of the goniometer at each reference angle.The variability from the mean angles was approximately less than 0.2 degree. r2 was 1 for each location. Intra & inter- rater reliability of the manual analysis were high.It was noted that the new introduced system, was reliable and precise enough so it could be utilized to measure the joint angles, especially for evaluating the JPS