On 15th May 2010 in Poland first computer planned total knee arthroplasty Vanguard Signature was performed and until now, including Orthopedic Traumatology Department of Central Clinical Hospital Ministry of Interior and Administration in Warsaw and Orthopedic Surgery Department of Promienista Clinic in Poznan, 65 patients have been operated with this method. The new system includes programming technical parameters of operation on the basis of diagnostic analysis of lower extremity using CT or MRI scans. Data are transmitted on Signature Positioning Guides (SPG) which implements function of navigation during surgery. Minimal bone resection, implants sizing and placement with reconstruction of mechanical axis of the limb provides proper functioning of the knee joint and reduces the risk of implants loosening. Further benefits include: instrument reduction, lower degree of femur trauma and reduction of average postoperative blood transfusion volume. The operator using Signature technology is required to have advanced knowledge in the conventional method TKR and medium level computer skills. Access to the program and materials and online communication with the Signature team in the USA allows the surgeon to modify the parameters of the operation and the necessary expert feedback. The rapid increase in the number of registered surgeons in Signature system shows a considerable interest in this technology.