The worldwide survival rate of total hip arthroplasties is improving: a systematic comparative analysis using worldwide hip arthroplasty registers

Purpose The aim of this study was to evaluate the development of the worldwide survival rate of primary total hip arthroplasty (THA). The hypothesis was that survival improved over the last decade in worldwide arthroplasty registers. Methods THA registers were screened in 2022 and compared between different countries with respect to the number of primary implantations per inhabitant, age, fixation type, and survival rate, and compared to similar data from 2009. The data from these reports were analyzed in terms of number, age distribution, and procedure type of primary THAs. Survival curves and a comparative analysis with respect to the development over time were calculated. Results We identified nine hip arthroplasty registers that contained sufficient data to be included. A large variation was found in the annual number of primary THA implantations per inhabitant, with more than the factor 4 for all age groups across regions. The procedure type varied strongly as well, e.g. in Sweden, 50% were cemented THAs, whereas in Emilia-Romagna (Italy), 96% of THAs were implanted cementless. We found an improved survival rate of 5%, with 90% of survival after 15 years in the cohorts from 2021 compared to 85% in the cohorts from 2009. Conclusion The present study revealed a significant improvement in the survival of THA in worldwide arthroplasty registers within different countries and regions over the period of one decade. We believe that it is safe to state that the success of THA is still rising with respect to this main outcome.