Standard prostheses are widely used for bone joints that have lost their function due to various pathologies, mainly because they have lower design and manufacturing times and costs. However, these do not fully adapt to the anatomy and diversity of the patients, often also needing to have available large amounts of surgical instruments to find the most appropriate ones for each specific patient. This work aims, on the one hand, to define a methodology for the design and manufacture of customised bone joint prostheses and, on the other hand, to show the application of that methodology on a prosthesis for the proximal interphalangeal (PIP) joint of the right index finger for a patient suffering from trauma-caused primary osteoarthritis. Using specific design and mesh manipulation softwares, a 3-D model of the components that make up this prosthesis will be obtained. Next, the G-code will be generated to build the prosthesis’ prototype using additive manufacturing techniques. The design of this prototype makes possible to encourage the personalised design of the surgical material necessary for the implantation of the prosthesis according to its characteristics, besides offering a solution to reduce discomfort, times and costs of surgery, and volume of the material used.