Outcome of Revision Surgery for Infection After Total Knee Arthroplasty: Results of 3 Surgical Strategies.

BACKGROUND: Periprosthetic joint infection (PJI) after knee arthroplasty surgery remains a serious complication, yet there is no international consensus regarding the surgical treatment of PJI. This study aimed to assess prosthesis survival rates, risk of revision, and mortality rate following different surgical strategies (1-stage versus 2-stage implant revision and irrigation and debridement with implant retention) that are used to treat PJI. METHODS: The study was based on 644 total knee arthroplasties (TKAs) that were revised because of a deep infection (i.e., surgically treated PJI) and reported to the Norwegian Arthroplasty Register (NAR) from 1994 to 2016. Kaplan-Meier and multiple Cox regression analyses were performed to assess implant survival rate and risk of revision. We also studied mortality rates at 90 days and 1 year after revision for PJI. RESULTS: During the follow-up period, 19% of the irrigation and debridement cases, 14% of the 1-stage revision cases, and 12% of the 2-stage revision cases underwent a subsequent revision because of a PJI. The 5-year Kaplan-Meier survival rate with revision for infection as the end point was 79% after irrigation and debridement, 87% after 1-stage revision, and 87% after 2-stage revision. There were no significant differences between 1-stage and 2-stage revisions with subsequent revision for any reason as the end point (relative risk [RR], 1.7; 95% confidence interval [CI], 0.9 to 3.5) and no difference with revision because of infection as the end point (RR, 1.6; 95% CI, 0.7 to 3.7). In an age-stratified analysis, however, the risk of revision for any reason was 4 times greater after 1-stage revision than after 2-stage revision in patients over the age of 70 years (RR, 4.3; 95% CI, 1.3 to 14.8). Age had no significant effect on the risk of subsequent revision for knees that had been revised with the irrigation and debridement procedure. The 90-day and 1-year mortality rates after revision for PJI were 1.2% and 2.5%, respectively. CONCLUSIONS: Irrigation and debridement yielded good results compared with previous published studies. Although the 1-stage revisions resulted in a fourfold increase in risk of subsequent revision compared with the 2-stage revisions in older patients, the overall outcomes after 1-stage and 2-stage revisions were similar. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Surgical procedures in the treatment of 784 infected THAs reported to the Norwegian Arthroplasty Register.

BACKGROUND AND PURPOSE: Controversies still exist regarding the best surgical procedure in the treatment of periprosthetic infection after total hip arthroplasty (THA). Based on data in the Norwegian Arthroplasty Register (NAR), we have compared the risk of re-revision after 4 different surgical procedures: 2-stage with exchange of the whole prosthesis, 1-stage with exchange of the whole prosthesis, major partial 1-stage with exchange of stem or cup, and minor partial 1-stage with exchange of femoral head and/or acetabular liner. METHODS: Between 1987 and 2009, 124,759 primary THAs were reported to the NAR, of which 906 (0.7%) were revised due to infection. Included in this study were the 784 revisions that had been performed by 1 of the 4 different surgical procedures. Cox-estimated survival and relative revision risks are presented with adjustment for differences among groups regarding gender, type of fixation, type of prosthesis, and age at revision. RESULTS: 2-stage procedures were used in 283 revisions (36%), 1-stage in 192 revisions (25%), major partial in 129 revisions (17%), and minor partial in 180 revisions (23%). 2-year Kaplan-Meier survival for all revisions was 83%; it was 92% for those re-revised by 2-stage exchange procedure, 88% for those re-revised by 1-stage exchange procedure, 66% for those re-revised by major partial exchange procedure, and it was 76% for those re-revised by minor partial exchange. Compared to the 2-stage procedure and with any reason for revision as endpoint (180 re-revisions), the risk of re-revision increased 1.4 times for 1-stage (p = 0.2), 4.1 times for major partial exchange (p < 0.001), and 1.5 times for minor partial exchange (p = 0.1). With infection as the endpoint (108 re-revisions), the risk of re-revision increased 2.0 times for 1-stage exchange (p = 0.04), 6.0 times for major partial exchange (p < 0.001), and 2.3 times for minor partial exchange (p = 0.02). Similar results were found when the analyses were restricted to the period 2002-2009. INTERPRETATION: In the Norwegian Arthroplasty Register, the survival after revision of infected primary THA with 2-stage implant exchange was slightly superior to that for 1-stage exchange of the whole prosthesis. This result is noteworthy, since 2-stage procedures are often used with the most severe infections. However, debridement with exchange of head and/or liner but with retention of the fixed implant (minor revision) meant that there was a 76% chance of not being re-revised within 2 years.