Indications for knee arthroplasty have remained consistent over time.

ABSTRACT

INTRODUCTION: Between 2004 and 2009, the incidence of primary total knee arthroplasty (TKA) in Denmark has almost doubled. It has been speculated that this increase may be a result of patients being operated on weaker indications. The purpose of this study was to compare preoperative degrees of osteoarthritis and health-related quality of life (QoL) in patients receiving primary TKA in 2004 and 2009. MATERIAL AND METHODS: We identified 154 and 369 primary TKAs inserted at our institution in 2004 and 2009, respectively. Patients had been invited to complete the Short Form (SF)-36 questionnaire preoperatively. Two groups of patients that were representative with regard to age and gender were randomly sampled and compared (n = 44 in 2004 versus n = 106 in 2009). The Kellgren-Lawrence (K-L) grade of osteoarthritis was assessed on preoperative radiographs in all patients. RESULTS: We found no statistically significant differences in gender distribution or mean age at surgery. We reached K-L grades of 3-4 in 52.4% and 49.6% in 2004 and 2009, respectively (p = 0.57). The preoperative mean SF-36 physical component scores were 32.6 and 33.7, respectively (p = 0.44). The preoperative mean SF-36 mental component scores were 43.0 in 2004 and 49.3 (i.e. 6.3 points higher) in 2009 (p = 0.003). CONCLUSION: Preoperative degrees of osteoarthritis and physical health-related QoL did not change from 2004 to 2009. Thus, it seems that these components of operative indications have not weakened. The increased preoperative SF-36 mental component score of these patients may have had a positive effect on postoperative outcomes. FUNDING: not relevant. TRIAL REGISTRATION not relevant. TRIAL REGISTRATION not relevant.