Short summary

Revision surgery after primary total hip arthroplasty (THA) due to prosthetic joint infection (PJI) is generally perceived as the most devastating complication due to impact on the patients' lives. According to large national registers there seems to be a tendency of seasonal influence on the incidence of PJI.

The primary aim of this study is to investigate previous infections as a risk factor and the influence of seasonal variation after primary THA.

Secondary aim is to identify the microorganisms and their resistance pattern involved in PJI leading to revision surgery.

Furthermore, it will investigate the risk of second revision after first revision due to PJI. This study will help developing new strategies for prophylaxis in order to reduce the complications and mortality rate. Surgery may be postponed or even cancelled in patients with clearly increased risk.

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Rationale

Revision of THA due to PJI is one of the worst complications due to its severe impact on patients' lives and the health care system. Little is known about the impact of previous infections, the influence of seasonal variation and the risk factors of second revision due to PJI. The underlying risk factors of the observed seasonal variation must be confirmed by further investigations. Such investigation can give new insights in prevention strategies for PJI and reduce complications and mortality rate.

Aim of study

The primary aim of this study is to investigate previous infections as a risk factor and the seasonal variation of revision due to PJI after primary THA due to osteoarthritis.

Secondary aim is to analyze the microorganisms involved in the infections leading to revision surgery. Furthermore, the risk of second revision after first revision due to PJI will be investigated.

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Description of the cohort

This is a population-based cohort study based on Danish Hip Arthroplasty Register on primary THA performed in Denmark from 2010 to 2019.

Data and biological material

Data from Danish Hip Arthroplasty Register will be retrieved to identify primary THA's due to osteoarthritis and revisions performed.

Data from microbiology database will be retrieved to identify the prosthetic joint infections by 2 positives out of at least 3 Kamme biopsies for the same microorganism.

Data from Danish National Database of Reimbursed Prescriptions will be retrieved to identify the community acquired antibiotic demanding infections within 6 months prior to primary THA.

Data from the National patient Registry will be retrieved to identify the hospital acquired/treated infections within 6 months prior to primary THA.

The above databases will be linked on personal level with the civil registration number.

Collaborating researchers and departments

Dept. of Clinical Microbiology, Vejle Hospital

• Jens Kjølseth Møller

Department of Infectious Disease Epidemiology and Prevention, Statens Serum Institut, Denmark

• Sophie Gubbels

Dept. of Orthopaedic Surgery, Bispebjerg Hospital

• Søren Overgaard

Dept. of Orthopaedic Surgery, Vejle Hospital

• Claus Varnum