A method and instruments to assemble an orthopaedic prosthesis is disclosed. The system may also include prosthetic trial components (1000), which may be used to size and select the components of the orthopaedic prosthesis. The system may include components of the orthopaedic prosthesis such as, for example, a prosthetic femoral component (16), a prosthetic tibial component (1284), a prosthetic stem (940) component, and a prosthetic sleeve component (1286).