Recent rehabilitation methods for physical impairments utilize various technologies such as robotic devices and gaming software in order to assist, motivate, and facilitate the recovery process. While most of the rehabilitation devices require external power sources, the triboelectric nanogenerator (TENG) has been proven as a reliable self-powered sensor that can also be used as an energy harvester. In this work, we utilize the TENG as a game controller as well as an exercise device for patients undergoing rehabilitation. We show that since the TENG can store energy, it serves as a motivating factor for the patient, as well as an index to monitor progression of rehabilitation and any improvements they make during rehabilitation. First, we describe the working principle of the TENG-based rehabilitation device (Rehab-TENG) and perform parametric studies to determine the performance of the device. Second, we developed a circuit to digitize the TENG output so that the patient could use the Rehab-TENG to control a computer game via Bluetooth. Third, the Rehab-TENG was employed as an energy harvester in an exercise system, where the patient moved their impaired arm to store energy into a capacitor. Based on the speed of capacitor charging, the level of impairment could be estimated. Finally, the patients were asked to answer a questionnaire where they emphasized the practicability of the device for its use as a home based rehabilitation system and the harvesting of energy as a motivating factor for them to move their impaired body part more than they normally would. We expect this study will enhance the potential of TENG use in healthcare as a practical tool for patient rehabilitation.