Computernavigation vs conventional technique in knee arthroplasty. A randomised, clinical and radiostereometric trial

Background: Computer navigation in knee replacement surgery is increasingly being used around the world, but the documentation of its usefulness is lacking. To critically evaluate this new surgical method, we want to perform a prospective, randomised clin ical trial. Goal: We evaluate the need for these highly advanced techniques in knee replacement surgery, and the cost-effectiveness. Long term outcome for the patients will be predicted by using the radiostereometric analysis (RSA). Also data from the Nor wegian arthroplasty register will indicate any difference in long term survival of the implant. If there is any difference in functional outcome or complication rate, between the two groups, this trial will detect that. Method: Patients age 60 through 80 years old, with gonarthritis, in need of knee replacement, are included in the trial. Radiostereometric analysis (RSA), CT-scans, X-rays, clinical evaluation score systems and laboratory measures are used in the evaluation process. A cost-effectiveness an alysis is performed based on data from Norwegian life tables, data from SINTEF and from the Norwegian arthroplasty register. Data from the Norwegian arthroplasty register will be statistically analysed separately, for all knee replacements done with compu ter navigation in Norway, the last 5 years. Four Norwegian hospitals cooperate in this trial (Haukeland university hospital, Haugesund hospital, Haugesund sanitetsforenings hospital for rheumatic diseases and Lovisenberg diakonale hospital) and patients a re recuited from all four hospitals. Scientific impact/challenges: This trial will probably have great impact since good evidence for using computer navigation in knee surgery is still lacking. It is important for the patient to be confident that he/she g ets the best treatment, and it is important for the health care providers and funding authorities to have clear evidence when choosing between two different treatment techniques, in order to gain the best benefit.