Detection, prevention and direct post-operative intervention in orthopaedic implant infection

In modern medicine, biomaterials are increasingly used to support or restore human body function. A biomaterial can be defined as man-made material designed to interact with living tissue or with body fluid. Joint prostheses, heart valves, external fixator pins, catheters, and contact lenses can all be considered examples of successful applications of biomaterials. Despite the fact that biomaterials have led to great improvements in medicine, they all have one thing in common: they tend to attract infectious micro-organisms leading to the occurrence of biomaterial-associated infections. The biomaterial itself then has become the focus of infection. These infections are mainly caused by direct contamination during surgery, but they can also be caused by haematogenous spread of bacteria from an infection site somewhere else in the human body. The clinically important step of bacterial attachment to the surface of a biomaterial is then followed by aggregation of other bacteria and growing of the bacteria, resulting in biofilm formation. The aim of this thesis is to investigate the reasons for diagnostic problems of infection in total joint prostheses in a University Hospital setting. Diagnostic problems are analyzed during the work up for revision surgery as well as during the peri-operative hospital stay after primary hip replacement. A possible method of preventing clinical signs of infection of a percutaneous orthopaedic implant, which is even more susceptible to infection than totally internal implants, is investigated in an animal model.