DHR – the Danish Hip Arthroplasty Register

The Danish Hip Arthroplasty Registry (DHR) was initiated by the Danish Orthopaedic Sociaty on January 1, 1995. DHR is a national clinical database on primary total hip arthroplasties, revisions, and follow-up examinations in Denmark. All public orthopaedic departments in Denmark,  as well as all privat hospitals performing hip arthroplasty report to the register.

  • To examine the epidemiology of total hip arthroplasty procedures in Denmark, including both primary operations and revisions.
  • To identify riskfactors of primary hip arthroplasty and revision.
  • To improve surgical technique through risk analyses.
  • To facilitate continuous improvement of the outcome of hip replacement surgery at both national and local levels.
  • To compare the Danish hip arthroplasty experience to that of other countries.
Number of hip arthroplasty procedures registered

In the period 1995-2014 a total off 139525 primary total hip arthroplasties and 22118 revisions have been registered in the DHR. The register can celebrate its 20 year anniversary with the coming yearly report.

Statistical analyses

The Department of Clinical Epidemiology, Aarhus University, Olof Palmes Alle 43-45, DK-8200 Aarhus C


The registered data include preoperative, peroperative, and postoperative information, prospectively collected using a standardized form. The standardized form A is to be filled in by the operating surgeon immediately after the operation, both primary total hip arthroplasty and revision. The standardized form B includes postoperative data, collected through follow-up examination. Registration of primary operations and revisions is compulsory, whereas recording of follow-up examinations is voluntary. However, patients can be followed-up several years after total hip arthroplasty, depending on the hospital´s routine only. Data are submitted in electronically or in paper form to the registry.

Validity of the registry

The overall completeness of registration for total hip arthroplasty procedures is 94%, and the diagnoses in patients undergoing primary surgery are confirmed in 84% of the patients after review of medical records and radiographs (Pedersen et al. Acta Orthop Scand 2004; 75(4): 434-441).


The registry publishes an Annual Report, which is sent to all participating departments, counties, the Danish National Board of Health and the Danish Orthopaedic Society. Participating departments also receive a local report allowing them to compare their own performance with the national performance.


The Registry is funded by Danish Regions via a database secretariat for financing of populationbased clinical and quality database. The registry has been affiliated to the Center for Clinical Databases, on Department of Clinical Epidemiology, Aarhus University. Consultants affiliated registry are working voluntarily.