1. Section of Orthopaedics, Department of Surgical Sciences, Uppsala University Hospital, Uppsala, Sweden;
2. The Swedish Hip Arthroplasty Register, Gothenburg, Sweden;
3. Department of Orthopaedics, Danderyd University Hospital Corp, Stockholm, Sweden;
4. Department of Clinical Sciences, Karolinska Institutet, Danderyd Hospital, Division of Orthopaedics, Stockholm, Sweden;
5. University of Groningen, Groningen, The Netherlands;;
6. Department of Orthopaedics, Institute of Clinical Sciences, Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden