Abstract: System, apparatus, and method for automatic detection of arthritis according to temperature asymmetry estimation in contralateral joints is presented. Simultaneously recorded thermogram and the optical image of an inspected joint and its contralateral joint are sent to the processing unit, where they are stored, processed, and analyzed. The system, apparatus, and method automatically detects outlines of joints in thermograms and optical images. Grid of points of interest is distributed inside the inspected and the contralateral joint's outline. Temperature maps are calculated according to both grids points and the temperature disparity map is estimated. The set of inflammation regions is obtained by analyzing the temperature disparity map and collecting adjacent points containing temperature differences surpassing the threshold. The system, apparatus, and method are non-invasive and non-contact, and suitable for real world environments with natural home or health care institutions background.