Patient-reported outcomes after fixed-versus mobile-bearing total knee replacement - A multi-centre randomised controlled trial using the Kinemax total knee replacement

University of Bristol, Bristol Implant Research Centre, Avon Orthopaedic Centre, Southmead Hospital, Bristol BS10 5NB, UK.
The Bone & Joint Journal (Impact Factor: 2.8). 10/2008; 90(9):1172-9. DOI: 10.1302/0301-620X.90B9.21031
Source: PubMed

ABSTRACT We compared patient-reported outcomes of the Kinemax fixed- and mobile-bearing total knee replacement in a multi-centre randomised controlled trial. Patients were randomised to the fixed- or the mobile-bearing prosthesis via a sealed envelope method after the bone cuts had been made in the operating theatre. Randomisation was stratified by centre and diagnosis. Patients were assessed pre-operatively and at eight to 12 weeks, one year and two years post-operatively. Validated questionnaires were used which included the Western Ontario MacMasters University, Short-Form 12, Mental Health Index-5, Knee Injury and Osteoarthritis Outcome Score for Knee-Related Quality of Life and Function in Sport and Recreation scales and a validated scale of satisfaction post-operatively. In total, 242 patients (250 knees) with a mean age of 68 years (40 to 80) were recruited from four NHS orthopaedic centres. Of these, 132 patients (54.5%) were women. No statistically significant differences could be identified in any of the patient-reported outcome scores between patients who received the fixed-bearing or the mobile-bearing knee up to two-years post-operatively.

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