According to various embodiments, provided is a prosthesis system for replacement of a head portion of a proximal radius. The system can include a first polymeric articulation component having a first locking portion and a metal head component having a second locking portion. The second locking portion can mate with the first locking portion to form a first locking mechanism to initially couple the first articulation component to the head component. The head component can define a locking channel. The system can also include a stem component having a protrusion receivable in the locking channel. The protrusion can define a bore, and the stem component can be adapted to be coupled to the radius. The system can also include a fastener received through the locking channel and into the bore to provide a second locking mechanism that couples the head component to the stem component.