Multipart component for an orthopaedic implant

An implant (10) to replace joints adjacent opposite ends of bones to a skeletal joint, the implant comprising: a first component to replace a portion of one of the joint ends of the opposing bones; a second component (12) to replace a portion of one of the joint ends of the opposing bones, the second component (12) means (24) for low friction articulation with the first component and means (26) for engaging with the first component to constrain the motion between the first and the second component, in which the means (24) for low friction articulation includes a first material exhibiting low wear and having a predetermined toughness value, and means (26 ) for engaging includes a second material having a predetermined toughness value higher than the means (24) for low friction articulation, characterized in that: (i) the first material comprises crosslinked polyethylene polyethylene yel second material comprises uncrosslinked; or (ii) the first material comprises polyethylene with a relatively high crosslink and the second material comprises polyethylene with a relatively light crosslinking.