Abstract
PURPOSE: Prosthetic infection is the worst complication in joint arthroplasty. The diagnostic procedure is time consuming and in many cases unrewarding. The aim of this investigation was to raise the sensitivity of the diagnostic procedure. METHODS: Altogether, 229 implants were removed from 229 patients. Complete data from 157 patients could be analysed. On explantation of the respective arthroplasty, tissue was removed, puncture fluid aspirated and biofilm scratched from the implant surface with a surgical knife. Specimens were investigated with conventional culture methods and with 16S ribosomal DNA (rDNA) polymerase chain reaction (PCR) and sequencing. RESULTS: In 123 cases, no pathogen could be identified by routine culture methods. In three of these culture-negative cases, bacteria could be identified with 16S rDNA sequencing of the removed biofilm. In 34 cases, bacteria could be identified with culture methods. In two of these cases, sequencing detected additional pathogens. CONCLUSIONS: The process of 16S ribosomal deoxyribonucleic acid polymerase chain reaction (rDNA PCR) and sequencing of biofilm removed from the explanted prosthesis is an important addition to conventional culture methods in prosthetic joint infection. Polymerase chain reaction detects additional pathogens and improves diagnostic sensitivity. The examination of tissue, puncture fluid and biofilm should be performed in cases of prosthesis loosening and explantation.