Computed gait analysis is a valid tool able to assess human walking. The joint angle variation during the cycle consists in a function. The derivation process, producing angular velocity and acceleration, may reveal and quantify the small angle variations. This approach may support physician’s interpretation of the joint movements. We would like to propose a calculation, combining the data from angular velocity and angular acceleration, to obtain a graph showing some features of joint behavior. We compared the results among a healthy subject, a coxarthrosis patient and a stroke patient. The built graph clearly shows the direction changes of the joint movements and the differences between the two sides and quantifies the acceleration/deceleration of a joint. The proposed approach is a mathematical artifice, which amplifies the information contained in the usual angle graphs and possibly opens the doors to more specific rehabilitation approaches.