A long-term follow-up study of unicompartmental replacement with a Marmor knee prosthesis and the introduction of a new ceramic prosthesis.

Unicompartmental replacement with a Marmor knee prosthesis was performed in 53 patients with unicompartmental osteoarthritis (OA). A five year or longer follow-up study of 15 joints in 13 of these patients was possible, three of which are now more than 10 years post-operative. All 13 patients reported absence of pain on weight-bearing and were able to flex the replaced knee more than 105 degrees. However, the postoperative femorotibial angle (FTA) appeared to be worsening with time, especially in those cases with an immediate postoperative FTA of more than 180 degrees. Since the needed size of the Marmor prosthesis is no longer available, we began using a ceramic prosthesis recently which we are introducing in this article.