This research aimed to develop an affordable device for the elbow and forearm rehabilitation to be used in Brazilian hospitals, clinics, physician’s offices, and residences. The Brazilian government made investments in technology development for social change, demanding innovative rehabilitation products manufactured with lower cost, compared to the current imported alternatives. Using research through design, we present the development of a module that allows continuous passive motion (CPM), which is a physical therapy resource indicated mainly for post-traumatic and post-surgical rehabilitation. This paper describes all design phases that resulted in this technological device with an important social impact on health care, making CPM treatment accessible to a broader range of patients. The module’s design fully contemplated Stakeholders’ needs, resulting in a working prototype. It was validated with users, producing the intended effects. The product is fully manufactured in Brazil and costs a fraction of the equipment currently used. The design presented in this paper opens a number of future research possibilities in the field of social innovation through health technology.