Joint replacement of the hip and knee remain
very satisfactory operations. They are, however, expensive. The
actual manufacturing of the implant represents only 30% of the final
cost, while sales and marketing represent 40%. Recently, the patents
on many well established and successful implants have expired. Companies
have started producing and distributing implants that purport to
replicate existing implants with good long-term results. The aims of this paper are to assess the legality, the monitoring
and cost saving implications of such generic implants. We also assess
how this might affect the traditional orthopaedic implant companies. Cite this article:
In a systematic review, reports from national registers and clinical studies were identified and analysed with respect to revision rates after joint replacement, which were calculated as revisions per 100 observed component years. After primary hip replacement, a mean of 1.29 revisions per 100 observed component years was seen. The results after primary total knee replacement are 1.26 revisions per 100 observed component years, and 1.53 after medial unicompartmental replacement. After total ankle replacement a mean of 3.29 revisions per 100 observed component years was seen. The outcomes of total hip and knee replacement are almost identical. Revision rates of about 6% after five years and 12% after ten years are to be expected.