Abstract: A shoulder endoprosthesis is disclosed herein. The endoprosthesis is configured as a modular unit of a stem and a cone body. Various sized and shaped stems may be selectively engaged with various sized and shaped cone bodies. Each stem is configured to be accommodated in an intramedullary canal of the humerous. Each cone body is configured to be accommodated in humerous. Each cone body further comprises a channel therethrough, a retaining section disposed within the channel, and an opening in a top end of the cone body configured to receive a mount member from one of a ball head and a reverse baseplate.