The Swedish Hip Arthroplasty Register

In 1975, Peter Herberts initiated a national study of all reoperations after total hip replacement (THR) in Sweden. This study was designed as a trial lasting for almost 2 years (1976–1977). The goal was to learn more about severe complications of THR and thereby improve on the results. It was considered impossible to collect all primary hip replacements because of the vast number of operations.

The pilot study was designed as a retrospective one to evaluate whether a number of key parameters associated with reoperation of total hip arthroplasties could be collected for statistical analysis at a national level. Importantly, it was decided that any further operation after the primary procedure, regardless of whether the implants were exchanged (revision) or not, should be used as failure parameter. Later on, it turned out that the choice of data collected was well suited to analysis of outcome, which contributed to the future success of the Register, not least by stimulation of continuous learning and improvement.

Almost all orthopedics departments performing hip replacements participated in this project, which eventually comprised 513 reoperations. One important experience was that complications were far more common after reoperations than after primary surgery. About a third of all reoperations were associated with further complications (Ahnfelt et al. 1980).

Encouraged by the success of this pilot study, the orthopedics profession in Sweden was again asked if the members would participate in a prospective and continuous national multicenter study of reoperations after THR. At the initiation of this National Register in January 1979, all (at that time 62) but 1 department, which joined somewhat later, accepted to participate. Peter Herberts, who initiated the pilot study, became the leader of the Register and continued in this capacity for 30 years.