Abstract
Purpose
The success rate of surgical debridement and prostheses retention for acute periprosthetic joint infection (PJI) is controversial. This study aims to report our experience in managing acute PJI following total knee arthroplasty (TKA) with surgical debridement and prostheses retention, and to identify the prognostic factors that may influence the surgical outcomes.
Methods
A retrospective review from our prospective joint replacement register in Queen Mary Hospital, Hong Kong, of patients who were managed with surgical debridement and prosthesis retention for acute PJI after TKA between 1998 and 2013 was performed. The diagnosis of acute PJI was based on the 2011 Musculoskeletal Infection Society (MSIS) PJI diagnostic criteria. Both the early post-operative infections and the late haematogenous infections were included (Tsukayama type 2 and 3). Surgical outcomes were defined as successful if patients’ clinical symptoms had been relieved; inflammatory marker levels including C-Reactive Protein (CRP), Erythrocyte Sedimentation Rate (ESR) and White Blood Cell (WBC) count had returned to normal; X-rays showed no prosthetic loosening; and no lifelong antibiotic suppression was required. Outcomes were defined as failed if patients required any further surgeries (e.g., re-debridement, one or two-stage revision), or needed lifelong antibiotic suppression. All Patients’ perioperative data, i.e., age, primary diagnosis, pre-operative CRP, ESR, WBC, haemoglobin, albumin, glucose level, time lag from symptoms onset to debridement, synovial fluid total cell count and bacteriology were traced and recorded. SPSS 22.0 was used to calculate and compare the statistical differences between surgically successful group and failed group regarding the factors above.
Results
34 patients with 35 TKAs were included. There were 19 female and 15 male. The primary diagnoses included 29 osteoarthritis (OA) and 5 rheumatoid arthritis (RA). 8 had history of diabetes mellitus (DM). 25 knees received primary TKA and 10 knees received revision TKA, including 6 revisions for PJI and 4 for aseptic loosening. 12 belonged to Tsukayama type 2 (early post-operative infection) and 23 belonged to Tsukayama type 3 (late haematogenous infection). During a mean follow-up time of 45.9±44.2 months, 12 were successfully treated while 23 failed, including 15 required re-operations and 8 needed lifelong antibiotic suppression. The success rate of debridement was 34.2%. Statistical analyses showed no significant differences between the two groups on patients’ age, time lag from symptoms onset to debridement, pre-operative CRP, ESR, WBC, haemoglobin, albumin, glucose level or synovial fluid total cell count. (Table 1) Patients’ primary diagnosis, previous revision surgeries or staphylococcal infections had no significant impacts on the surgical outcome, either. Debridement with polyethylene insert exchange, however, had a significantly higher success rate than debridement alone. (Table 2)
Conclusions
We concluded that debridement with prosthesis retention has a low success rate for acute periprosthetic infection in TKA. No significant prognostic factors could be identified, except that debridement with polyethylene insert exchange has higher success rate than debridement alone.