S08.1 TREATMENT OF INFECTED KNEE ARTHROPLASTIES: A COMPARATIVE STUDY OF THREE METHODS

Abstract

3462 knee prosthesis were implanted between 1.1.1998 and 31.12.2008 (11 years). There were 491 Unis in this group, but infection ocurred only in Total Knee Replacement (TKR) group. We treated 24 patients (0,69 % infection revision rate) with infected TKR in this time period. The follow-up was from 126 to 7 months. The infection agens was diagnosed by preoperative joint aspiration (Staph.aureus 40%, koagulaseneg.Streptococci 20%)

We compared 3 methods of treatment: the first group was open debridement + inlay exchange. In this group we treated 10 patients (37%). There was infection recurrence in 20 %.

The second group was one-stage exchange: 5 patients (18%) with infection recurrence 60% and two complications (spin-out and component loosening).

The third group was two-stage exchange: 12 patients (44%) without infection recurrence (0%) and no complications. Two stage-exchange was performed with custom-made cement tibialspacer and resterilized explanted femoral component which was reimplanted with [[Unsupported Character – & #8222;]]poor“ cement technique as originally described by A.Hofmann. Post-op partial to full-weight bearing with brace 0–90 degrees was allowed. For reimplantation a non- or semiconstrained revision prosthesis with mobile bearing after cca 6 weeks period was used. The prothesis‘ stems were not cemented.

Based on our experience we recommend two-stage revision in mostly cases. Use of mobile spacer keeps excellent mobility after revision and prevent excesive scarings which complicate the reimplantation and causes limitation of movement if fixed spacer was used. On the other side we could show that use of mobile spacer do not increase infection recidiv rate in septic knee surgery. A meticulous debridement is, in our opinion, the most important part of surgery, but it was possible in all cases to save the collateral ligaments and to prevent use of constrained revision prosthesis with increased revision rates because of loosening. Debridement + inlay exchange should be limited only for acute cases with short disease history.