Abstract
Periprosthetic joint infection (PJI) following total knee arthroplasty (TKA) is a
severe complication causing a significant burden. The study aims were to establish
the epidemiology of microorganisms in TKA PJI, the rate of persistent infection requiring
further surgery, and the risk factors for this. Microbiological specimens between
June 2002 and March 2017 at five regional hospital sites were identified with revision
TKA procedures in the National Joint Replacement Registry. The time between procedures,
type of revision strategy, and any subsequent further revision operations were collected.
At minimum 2-year follow-up, 174 revision TKA were identified, with a mean patient
age of 69 ± 11 years. A broad range of pathogens were identified. Fifty cases (29%)
had persistent infection requiring at least one further operative procedure, 13 cases
required 3 or more. Coagulase-negative Staphylococcus species (CNS) was seen most with failed surgery, polymicrobial infections also posing
a significant risk factor. The best chance of a successful PJI surgical strategy was < 12
months from primary TKA, with the greatest risk between 3 and 5 years (p < 0.05). Younger age significantly increased the risk of further surgery (p < 0.05). Management varied; 103 (59%) debridement, antibiotic therapy and implant
retention, with further surgery in 29%; 45 (17%) single-stage revision, with further
surgery in 13%; and 26 (15%) two-stage revision, with further surgery in 12%. This
study presents the most common causative pathogens for PJI in TKA, and the high rate
of persistent infection after initial revision surgery. Risk factors for persistent
infection and further revision surgery were polymicrobial and CNS infections, patients
who presented between 3 and 5 years following primary TKA, and younger age. This study
therefore raises important risk factors and areas for future research to reduce the
burden of multiple operations after PJI.
Keywords
prosthetic joint infection - infected - total knee arthroplasty - revision total knee
arthroplasty - microorganisms - unplanned revision - age