Knee arthroplasty in Denmark, Norway and Sweden
Source: Acta Orthopaedica, Volume 81, Number 1, February 2010 , pp. 82-89(8)
Publisher: Informa Healthcare
Background and purpose The number of national arthroplasty registries is increasing. However, the methods of registration, classification, and analysis often differ.
Methods We combined data from 3 Nordic knee arthroplasty registers, comparing demographics, methods, and overall results. Primary arthroplasties during the period 1997––2007 were included. Each register produced a dataset of predefined variables, after which the data were combined and descriptive and survival statistics produced.
Results The incidence of knee arthroplasty increased in all 3 countries, but most in Denmark. Norway had the lowest number of procedures per hospital——less than half that of Sweden and Denmark. The preference for implant brands varied and only 3 total brands and 1 unicompartmental brand were common in all 3 countries. Use of patellar button for total knee arthroplasty was popular in Denmark (76%) but not in Norway (11%) or Sweden (14%). Uncemented or hybrid fixation of components was also more frequent in Denmark (22%) than in Norway (14%) and Sweden (2%).
After total knee arthroplasty for osteoarthritis, the cumulative revision rate (CRR) was lowest in Sweden, with Denmark and Norway having a relative risk (RR) of 1.4 (95% CI: 1.3––1.6) and 1.6 (CI: 1.4––1.7) times higher. The result was similar when only including brands used in more than 200 cases in all 3 countries (AGC, Duracon, and NexGen). After unicompartmental arthroplasty for osteoarthritis, the CRR for all models was also lowest in Sweden, with Denmark and Norway having RRs of 1.7 (CI: 1.4––2.0) and 1.5 (CI: 1.3––1.8), respectively. When only the Oxford implant was analyzed, however, the CRRs were similar and the RRs were 1.2 (CI: 0.9––1.7) and 1.3 (CI: 1.0––1.7).
Interpretation We found considerable differences between the 3 countries, with Sweden having a lower revision rate than Denmark and Norway. Further classification and standardization work is needed to permit more elaborate studies.
Document Type: Research Article
Affiliations: 1: 1The Swedish Knee Arthroplasty Register, Dept of Orthopedics, Clinical Sciences, Lund. Lund University, Sweden 2: 2Swedish National Musculoskeletal Competence Centre (NKO), Lund, Sweden 3: 3The Norwegian Arthroplasty Register, Department of Orthopaedic Surgery, Haukeland University Hospital, Bergen, Norway 4: 5Danish Knee Arthroplasty Register and Competence Centre North, Department of Clinical Epidemiology, Aarhus University Hospital, Denmark 5: 6The Danish Knee Arthroplasty Register and Department of Orthopaedics, Aarhus University Hospital, Denmark.
Publication date: February 1, 2010