Mobile-bearing knee replacement: Clinical results - A review of the literature

Mobile-bearing knee replacements have been implanted for more than 20 years . The Oxford unicompartmental replacement and the LCS (low contact stress) total knee system have been studied extensively. Ninety-five to 97% 10-year survivorship rates of the Oxford unicompartmental replacement have been re ported. Low contact stress meniscal-bearing survivorship rates of 98% at 6 years and 94.6% at 8 years have been reported. Ninety-five to 100% survivor ship rates at the 11- and 12-year followup have been reported for low conta ct stress rotating platform knee replacements. Complications with the Oxfor d unicompartmental replacement include an increase in bearing dislocation a nd an increase in loosening rate when the components were placed in knees t hat had anterior cruciate ligament deficiency. Complications with the low c ontact stress total knee system include bearing dislocation (meniscal, rota ting platform, and patellar), bearing breakage, and polyethylene wear. If m obile-bearing knee replacements are inserted with the same precision as fix ed-bearing knee replacements, the results should at least be comparable. Th ere may be some potential for an increase in durability, compared with fixe d-bearing knee replacements, especially those of a modular design.