The CapFlex PIP prosthesis is an innovative joint replacement for the second knuckle. In order to meet the anatomical requirements of individual patients, the modularly designed components are available in a range of sizes. The advantages for the patient resulting from the new design are a primary solid bone anchorage, the improved lateral joint stability and the optimised conditions for revision. For a safe step-by-step implantation intuitive, colour-coded instruments are available.