After successful use of the preparatory prosthesis any information learned from how the patient performed and/or any modifications made to ensure successful use are considered in the development of the definitive device. While often changes to the residual limb are the most significant occurrence, functional needs are also assessed to determine what changes to socket configuration or component selection are required. These factors may include the selection of a different socket suspension system as well as different performing prosthetic feet. In addition, for the above knee user, there are a number of knee options to enhance stability and safety. If not used on the initial prosthesis application of microprocessor knee technology is often considered. These knees are designed to sense and respond by better matching computer collected data based on how the individual walks. They have the ability to instantly increase or decrease resistance to the knee joint whether on level or uneven surfaces. These knees can also distinguish between stair and ramp activities and adjust themselves accordingly.