[Infected knee prostheses. Part 2: chronic late infections]

Treatment of late and chronic infections, which require the replacement of all the infected implant material.

All infections lasting more than 4 weeks that have been proven to be bacterial and/or obvious signs of infection.

Unsuitable for anesthesia, high acute infection with sepsis and risk for bacteremia with danger to life, large soft tissue damage where plastic surgery coverage is not possible.

Arthrotomy, synovectomy, removal of all foreign bodies including all residue of polymethylmethacrylate (PMMA), jet lavage, spacer, drainage, wound closure or temporary closure using vacuum sealing.

Bed rest with a leg brace and drainage until daily drainage volume is <50 ml, then mobilization with no weight-bearing in an orthesis, 4 weeks systemic antibiotics, after 2 weeks without antibiotics aspiration of the joint, when no bacteria are found reimplantation of a revision TKA (total knee arthroplasty) and with plastic surgery for coverage (gastrognemius flap) if necessary, when bacteria are found again revision with exchange of the spacer.

In the literature, the success rate for both the one-stage or the two-stage procedure is about 80-95%. In our very nonhomogeneous collective the overall rate of success is about 81%.