Clinical results of the initial cemented and cementless series of 233 New Jersey Low Contact Stress Rotating Platform Knee Replacements in 184 patients surviving at least 10 years were analyzed using a strict knee scoring scale. The study showed excellent (46.7%) and good (53.3%) results in primary cemented rotating platform knee replacements, and excellent (68.1%), good (29.8%), and fair (2.1%) results in primary cementless rotating platform knee replacements. Radiographic evaluation at a minimum 10-year follow-up showed stable fixation of all components, no gross migration but significant osteolysis requiring bearing exchange, and bone grafting in three cementless rotating platform knee replacements (1.8%) in three patients who underwent previous surgeries at an average 10.2 years from the index surgery. Survivorship of the patients who underwent primary cemented rotating platform knee replacements with end points of revision for any mechanical reason or a poor clinical knee score was 97.7% at 10 and 20 years. Survivorship of the patients who underwent cementless rotating platform knee replacements with end points of revision for any mechanical reason or a poor clinical knee score was 98.3% at 10 and 18 years.