[Transfemoral amputation due to uncontrollable infections after implantation of a total knee endoprosthesis].

Introduction: In the evaluation of an internal analysis of data on the increased effort for nursing during rehabilitation of patients with amputations in the Baumrainklinik of the HELIOS Rehabilitation Center Bad Berleberg, the number of patients with transfemoral amputations (TFA) due to uncontrollable multiple infections after implantation of a total knee endoprosthesis (total knee arthroplasty, TKA) was clearly emphasized.

Objective: This article discusses the results of a retrospective, patient-controlled trial (PCT) and compares these with the data of the German Endoprosthesis Registry (EPRD). The study concentrated on patients who were admitted to rehabilitation after a TFA due to an uncontrollable infection after implantation of a knee TKA. The primary aims were the identification of patients who developed an uncontrollable infection after TKA with subsequent TFA and the comparison with national and international revision and amputation rates after TKA.

Method: An analysis of the medical history questionnaire was carried out for all 787 patients with amputation of the lower extremities who underwent rehabilitation in the time period from 1st January 2007 to 31st December 2015. The patient records were systematically analyzed based on the standardized documentation methods of the medical and nursing personnel using the Barthel index, the activity/function classes, phantom pain and length of stay, including demography, infection history and insurance company.

Results: The analysis showed that 10 patients, 2.29% of all TFA, suffered the loss of a lower extremity due to an uncontrollable TKA infection. The revision rate 3 years after primary TKA in Germany is 3.0% (EPRD annual report 2023), whereas values of 1-4% are given in the international literature (status 2020). In the patient group of the EPRD, in 2022 revision surgery was necessary due to an infection in 15.0% of the cases. The current statistics of the EPRD (annual report 2023) show that 3 years after the initial revision surgery due to an infected TKA another revision was necessary in 23.5-30% of cases.

Conclusion: These numbers are alarming and should be critically evaluated and monitored. The future aim is to identify the causes of infections, systematic errors in the TKA and the pathogens that lead to infections after TKA and to correlate the associations.