| 摘要 |
<p>An acetabular prosthesis includes a hemispherical metal shell (60) for fixation to bone and a composite bearing (80) insert for receipt within the shell (60). The composite bearing insert (80) includes an inner plastic portion (80) having a plastic bearing surface defining a bearing concavity for receipt of and articulation with a head of an implantable femoral component. The composite bearing insert (80) further includes an outer metal portion (60) fixed thereto against relative movement and having a metal male conical taper surface. The interior of the metal shell has a female conical taper surface for engaging the male conical taper surface in a taper locked relationship to secure the composite bearing insert (80) within the shell (60). The inner plastic portion (80) and the outer metal portion (60) have a mutually engaging protrusion and groove that are assembled by cooling and shrinking the plastic portion relative to the metal portion during assembly. The interface between the shell (60) and the composite bearing (80) is entirely metal, thereby preventing plastic to metal micromotion and generation of polyethylene debris.</p> |
