A method for carrying out a functional analysis on a person equipped with an artificial extremity having adjustable settings. The method includes the steps of providing a sensor assembly configured as a replacement for a part of the artificial extremity and installing the sensor assembly in place of the part. Forces, accelerations and/or torques are then measured with the sensor assembly during use of the artificial extremity by the person and the settings of the artificial extremity are optimized based on these measurements. The sensor assembly is removed and the replaced part is installed back into the artificial extremity, while retaining the optimized settings. In one embodiment, the artificial extremity is a leg prosthesis having an artificial knee joint with a rotational adaptor mounted above it. The sensor assembly then replaces the rotational adaptor.
