The sale of a medical system was subject to Missouri sales and use tax since the system did not qualify as an exempt orthopedic or prosthetic device. The medical system consists of three parts – an implant, a wireless controller, and a charger – and can be used by a patient to administer electric shocks to alleviate chronic pain. Missouri regulations define a prosthetic device as “a device that replaces all or part of the function of a permanently inoperative or malfunctioning internal body organ and is medically required.” Missouri regulations define orthopedic device as “a rigid or semi-rigid leg, arm, back or neck brace and casting materials which are directly used for the purpose of supporting a weak or deformed body member or restricting or eliminating motion in a diseased or injured part of the body.” The medical system in this case does not meet either of these definitions. The system provides electrical shocks in a way that is not performed by any organ in the body. Rather, it is tangible personal property subject to Missouri sales and use tax. (Letter Ruling No. LR 8043, Missouri Department of Revenue, July 19, 2019)