Search

Background and purpose The possibility of comparing results and of pooling the data has been limited for the Nordic arthroplasty registries, because of different registration systems and questionnaires. We have established a common Nordic database, in order to compare demographics and the results of total hip replacement surgery between countries. In addition, we plan to study results in patient groups in which the numbers are too small to be studied in the individual countries. Material and methods Primary total hip replacements (THRs) from 1995-2006 were selected for the study. Denmark, Sweden, and Norway contributed data. A common code set was made and Cox multiple regression, with adjustment for age, sex, and diagnosis was used to calculate prosthesis survival with any revision as endpoint. Results 280,201 operations were included (69,242 from Denmark, 140,821 from Sweden, and 70,138 from Norway). Females accounted for 60% of the patients in Denmark and Sweden, and 70% in Norway. Childhood disease was the cause of 3.1%, 1.8%, and 8.7% of the operations in Denmark, Sweden, and Norway, respectively. Resurfacing of hips accounted for 0.5% or less in all countries. The posterior approach was used in 91% of cases in Denmark, 60% in Sweden, and 24% in Norway. Cemented THRs were used in 46% of patients in Denmark, in 89% of patients in Sweden, and in 79% of patients in Norway. Of the 280,201 primary THRs, 9,596 (3.4%) had been revised. 10-year survival was 92% (95% CI: 91.6-92.4) in Denmark, 94% (95% CI: 93.6-94.1) in Sweden, and 93% (95% CI: 92.3-93.0) in Norway. In Denmark, 34% of the revisions were due to dislocation, as compared to 23% in Sweden and Norway. Replacement of only cup or liner constituted 44% of the revisions in Denmark, 29% in Sweden, and 33% in Norway. Interpretation This unique common Nordic collaboration has shown differences between the countries concerning demographics, prosthesis fixation, and survival. The large number of patients in this database significantly widens our horizons for future research. [ABSTRACT FROM AUTHOR]

Background Childhood hip disorders including acetabular dysplasia, congenital hip dislocation, epiphysiolysis, and morbus Calve-Legg-Perthes are well-established risk factors for the development of early osteoarthritis of the hip. These patients have an increased risk of undergoing a total hip arthroplasty (THA) operation early in their life. However, there are very few data on implant survival in such patients. Methods We used data from the Danish Hip Arthroplasty Registry to identify patients who had been treated with a primary THA in Denmark between 1995 and 2005. Implant survival during early and late postoperative follow-up (< 6 months and>6 months, respectively) was assessed for patients treated with a primary THA due to childhood hip disorders, and compared with implant survival for THA patients with primary osteoarthritis. Results 56,087 THA procedures included 53,694 (96%) hips with primary osteoarthritis, 890 (1.6%) with acetabular dysplasia, 565 (1.0%) with congenital hip dislocation, 267 (0.5%) with epiphysiolysis, and 404 (0.7%) hips with morbus Calve-Legg-Perthes Patients with acetabular dysplasia had an increased risk of revision during the 0-6-month postoperative period compared to patients with primary osteoarthritis (adjusted relative risk (RR)=1.9 (95% CI: 1.2-3.1)). These revisions were mainly performed due to dislocation of the THA, providing an adjusted RR of revision due to dislocation of 2.8 (95% CI: 1.6-4.9) compared to patients operated due to primary osteoarthritis. We found no statistically significant differences in risk of revision for the other childhood hip disorder groups during the early postoperative phase. In addition, we found no substantial differences in revision risk during later follow-up (0.5-12 years) for any of the childhood hip disorders compared to patients with primary osteoarthritis. Interpretation We found an encouraging rate of long-term implant survival for patients with childhood hip disorders. The major concern is the increased risk of revision because of dislocation in the first 6 postoperative months for patients with acetabular dysplasia. However, the advent of alternative bearings and the use of large-diameter femoral heads may improve the outcome after primary THA in these patients. [ABSTRACT FROM AUTHOR]

Background We examined incidence rates (IR) of total hip arthroplasty (THA) in Denmark according to county and type of hospital, and investigated possible factors associated with any variations. Methods Through the Danish Hip Arthroplasty Registry, we identified all cases of primary THAs (n = 37,144) and revisions (n = 6,446) between 1996 and 2002. Unadjusted and age- and gender-standardized, hospital type- and county-specific IRs were calculated. Using multiple regression analysis, we examined possible factors associated with the variations. Results Over the study period, age- and sex-standardized IRs of primary THAs for university and other hospitals increased by 10% and 40%, respectively. IRs of revisions increased for other hospitals by 33%, but decreased for university hospitals by 30%. Unadjusted IRs varied among counties (n = 15), which remained despite age- and gender-standardization. The IR ratio was 1.4 (95% CI: 1.3-1.6) when comparing the counties with the highest and lowest IRs. No association was found between IRs of THA and the number of orthopedic surgeons per 100,000 inhabitants, proportion of patients with primary arthrosis, preoperative Harris Hip Score, hospital costs, the counties' Gross Domestic Product, or population density. Interpretation Substantial regional differences in the IRs of THA procedures were found. We found no associations between IRs and a range of patient- and healthcare system-related factors. [ABSTRACT FROM AUTHOR]

Background The annual number of total hip arthroplasties (THA) has increased in Denmark over the past 15 years. There is, however, limited detailed data available on the incidence of THAs. Methods We calculated the incidence rates (IR) of primary THA and revision in Denmark between 1996 and 2002 and estimated the demands for primary THA in Denmark until 2020. We used data from the Danish Hip Arthroplasty Registry, a nationwide and popula-tion-based clinical database, to identify patients who had undergone primary THA (n = 37 144) or revision arthroplasties (n = 6 446). Age and sex-specific data on the Danish population were obtained from the StatBank Denmark. All IRs were standardized according to two standards, i.e. the Danish population in 1996 and the European standard population (18 age groups). The future demands for primary THA were estimated using the age and sex-specific incidence of primary THA for 2002 as a reference, and taking into account the expected changes in the age distribution of the population and the trend in IRs seen in Denmark between 1996 and 2002. Results The annual overall standardized IRs of primary THAs and revisions increased from 101 (95% confidence interval (CI): 97.6–104) to 134 (CI: 131–138) and from 19.2 (CI: 17.9–20.5) to 21.1 (CI: 19.8–22.4) per 100 000 inhabitants from 1996 to 2002, respectively (IRs adjusted to the Danish population in 1996). The IRs of primary THAs and revisions increased by 30% and 10% during this period. The relative increase in IRs of primary THAs was found to be similar in both women and men. The increase was higher among patients aged 50–59 years, however. Furthermore, a decrease in IRs was seen in patients who underwent primary THA due to rheumatoid arthritis. IRs of primary THAs have been estimated to increase by 22% in 2020 compared with 2002, based only on the expected changes in the age distribution of the population. However, assuming that the annual age and sex-independent increase in the IRs seen in the period 1996–2002 will continue, the IR of primary THA is estimated to increase by as much as 210% in 2020. Interpretation The overall annual standardized IRs of primary THAs and revisions in Denmark increased during the period from 1996 to 2002. Moreover, the demands for THA procedures in the coming decades may exceed the current capacity due to the ageing population and a continued age and sex-independent increase in surgical activity. [ABSTRACT FROM AUTHOR]