Background and Aim: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.

Material and Methods: 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 transparent sheets and goniometry.

Results: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.

Conclusion: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.