The purpose of this study is to present midterm results of NexGen LPS (Zimmer, Warsaw) rotating platform total knee arthroplasty. A prospective consecutive series of 50 primary rotating platform total knee replacements in 43 patients were clinically and radiographically evaluated at a mean follow-up of 46.4 (range 30-78) months. There were 12 men (30%) and 31 women (70%) with an average age of 72.3 years (range 55-85). All implants were cruciate-substituting and cemented. Patients were assessed using the Knee Society Clinical Rating System and the Knee Society Total Knee Arthroplasty Roentgenographic Evaluation and Scoring System. Pre-operatively, the mean knee score was 50.7 points (SD 15.1) and the mean function score was 40.5 points (SD 22.7). Post-operatively the mean knee score was 91.6 (SD 6.5) and the mean function score was 85.9 (SD 17.4). No sign of component loosening or osteolysis could be identified. The NexGen LPS rotating platform total knee replacement design provided excellent mid-term clinical and radiographical results.