An implant (20) prosthesis and method of use are described. The implant comprises an articulation component (24) having a bearing surface (60) and a reverse surface (62) arranged to couple to a proximal neck portion (26) of an arthroplasty implant (22) coupled to a bone. A collar (28) is arranged to couple to the reverse surface of the articulation component. The collar defines a neck hole (70) arranged to pass around the coupling between the articulation component and the proximal neck portion of the arthroplasty implant. The collar and the articulation component comprise complementary coupling features to secure the collar to the articulation component. The collar further comprises a plurality of attachment portions (74) to couple the collar to bone fragments or soft tissues. The prosthesis comprises the implant and an arthroplasty implant having a distal portion arranged to be coupled to an end of a long bone and a proximal neck portion.
