Indications for hip and knee replacement in Sweden Sofia Löfvendahl MSc, 1 Svetlana Bizjajeva PhD, 2 Jonas Ranstam PhD 2 and Lars Lidgren MD PhD 3 1 Economist, 2 Statistician, Swedish National Musculoskeletal Competence Centre (NKO), Lund University Hospital, Lund University, Lund, Sweden 3 Professor, Department of Orthopedics, Clinical Sciences Lund, University Hospital, Lund University, Lund, Sweden Keywords indications, joint replacement, logistic mixed model with random effect, osteoarthritis, priority criteria Correspondence Sofia Löfvendahl Swedish National Musculoskeletal Competence Centre (NKO) Lund University Hospital Lund University SE-221 85 Lund Sweden E-mail: sol@nko.se Ethical approval: the study has been approved by the Regional Ethical Committee in Lund, Sweden. Accepted for publication: 27 November 2009 doi:10.1111/j.1365-2753.2010.01430.x Abstract Objectives The aim of this paper was to compare selected indication parameters for patients scheduled for hip and knee replacement at orthopaedic units in Sweden. Methods Swedish orthopaedic clinics performing joint replacement were invited to enrol in the study. The study time was set to 2 years (from June 2006 to June 2008). The study subjects were patients undergoing hip or knee replacement for osteoarthritis (OA). For data collection, we used a Swedish priority criteria tool based on a translation from a form used in Canada with minor changes. The reliability and validity of the Swedish tool were investigated, with good reproducibility. The questionnaires (one for the doctor and one for the patient) were completed during decision making for surgery. Results Eleven hospitals enrolled in the study. In total, 2961 patients were included during the study period. Among these, 1662 were hip replacement patients and 1299 were knee replacement patients. The vast majority of patients undergoing hip or knee replacement had findings indicating severe OA, both clinically and radiologically according to the clinical priority tool. Statistically significant self-reported problems with pain at rest, walking and impaired activities of daily living were also observed. There were statistically significant differences in reported indications between the hospitals, both for hip OA patients and for knee OA patients. Conclusions A clinical priority criteria tool is a useful means of following changes in indications for certain procedures. It could also contribute to explaining differences in case mix when evaluating clinical outcome and patient satisfaction. Introduction Today, hip and knee replacements are highly cost-effective ortho- paedic procedures [1], partly because of improved surgical tech- niques and implants giving long-lasting pain relief and improved health-related quality of life [2–4]. There is a high and increasing prevalence of symptomatic hip and knee osteoarthritis (OA), espe- cially in the western world [5]. According to the data in the Swedish Hip Arthroplasty Register, 11 715 primary total hip replacements for primary hip OA were performed in 2007 [6]. The corresponding figure in 2000 was 8772. The Swedish Knee Arthroplasty Register statistics show that 10 380 and 6063 total knee replacements were performed in 2007 and 2000, respectively [7]. In 2007, the Swedish population was approximately 9 million [8]. In the Swedish arthroplasty registers, there are, however, clear variations in the provision of hip replacements and knee replace- ments across the country [9–11]. Similar patterns have been found using data extracted from the Swedish Hospital Discharge Register [12]. Other European countries and the USA have also reported differences in the provision of hip and knee arthroplasties, both within and between countries [13–15]. This variability cannot only be explained by differences in disease prevalence, different popu- lation demographics or differences in health care systems [5,16]. It has also been argued that variation in orthopaedic surgeons’ opinion about indications for surgery may to some extent explain the differences in the provision of hip and knee replacement [3,5,16,17]. The surgeon’s opinion and advice may also influence the patient’s decision about when, or if, to proceed with surgery [17]. The overall aim of this study was to determine whether there are systematic differences between Swedish orthopaedic clinics with regard to selected indication parameters for patients to be given a hip replacement or a knee replacement for primary OA. We also investigated whether there were any differences between the two patient groups regarding indication parameters. The indication parameters analysed in the study were as follows: (1) presence of radiological signs of OA in the hip or knee; (2) presence of signs of OA (limited range of motion, deformities, joint swollenness, instability or tenderness on Journal of Evaluation in Clinical Practice ISSN 1365-2753 © 2010 Blackwell Publishing Ltd, Journal of Evaluation in Clinical Practice 17 (2011) 251–260 251