High-concentration continuous local antibacterial perfusion therapy: safety and potential efficacy for acute and chronic periprosthetic knee joint infection.

Background: Periprosthetic joint infections (PJIs) following total knee arthroplasty (TKA) are among the most challenging pathologies to manage. Recently, continuous local antibiotic perfusion (CLAP) therapy has been introduced for treating musculoskeletal infections in orthopedics. This study aimed to determine the outcomes and risks of CLAP therapy combined with conventional treatment for PJIs after TKA.

Methods: We retrospectively evaluated 14 patients with PJIs. For acute PJIs, CLAP therapy was performed alongside debridement, intravenous antibiotics, and implant retention. For chronic PJIs, a two-stage revision with CLAP therapy and intravenous antibiotics was performed. Implants were replaced with a cement mold incorporating CLAP therapy, followed by revision surgery after 3 months. For all patients, 120 mg/day of gentamicin (GM) was locally administered into the knee joint for 2 weeks as part of CLAP therapy, in combination with perioperative intravenous antibiotics.

Results: Five patients developed acute PJIs, and nine developed chronic PJIs after TKA. The mean follow-up period was 18.4 (15.2-21.1) months. All five patients with PJIs treated with one-stage surgery (debridement and insert exchange only) successfully preserved their implants. Among the nine patients with chronic PJIs, seven underwent CLAP therapy combined with two-stage revision surgery, resulting in successful treatment without relapse, whereas the remaining two patients were initially treated with one-stage surgery and CLAP therapy but failed to retain their implants, and subsequently required additional two-stage revision surgery, which ultimately succeeded. No adverse effects from GM were reported.

Conclusions: Our results suggest that CLAP therapy is safe and may be effective for treating acute and most chronic PJIs after TKA.