DAIR in treating chronic PJI after total knee arthroplasty using continuous local antibiotic perfusion therapy: a case series study.

BACKGROUND: Antimicrobial agents are administered via intramedullary antibiotic perfusion (iMAP)/intrasoft tissue antibiotic perfusion (iSAP) to infected lesions to control osteoarticular and soft tissue infections. Continuous local antibiotic perfusion (CLAP) has been reported to be useful. This study aimed to investigate the outcomes of DAIR combined with CLAP for chronic PJI after total knee arthroplasty performed at our hospital. SUBJECTS AND METHODS: Six patients (male; one case, female; five cases, mean age 79.5 years (70-94)) underwent CLAP for chronic PJI after TKA at our hospital between July 2020 and June 2022. They were followable for at least one year after surgery. Seven months (17-219), with a mean follow-up of 24.3 months (12-36). In addition to direct debridement and insert exchange, systemic antimicrobial treatment, and CLAP with gentamicin were performed using NPWT. We investigated the organisms causing the inflammation, the duration of iMAP/iSAP implantation, the maximum daily dose of GM, the maximum GM blood concentration, and the presence or absence of GM-induced adverse events. RESULT: Two of six patients had a recurrence of infection at five weeks and five months after initial CLAP and required repeat CLAP treatment, but all patients could preserve their components. The organisms responsible for the flare-ups were MSSA in three cases: ESBL-producing E. coli, mixed MSSA and streptococcal infection, Klebsiella pneumonia in one case each, and unknown pathogens in one case. CLAP therapy for all patients was administered eight times in 6 cases: iMAP, mean: 10.0 days (5-16); iSAP, mean: 19.3 days (15-28); GM dose, mean: 162.5 mg/day (80-240); and GM blood concentration, mean: 1.4 µg/mL (0.2-5.0). Adverse events included one case of reversible acute kidney injury during CLAP in a patient with recurrent infection. DAIR with CLAP for chronic post-TKA infection can be a useful treatment option to preserve components and allow the infection to subside, provided the implant is not markedly loosened.

Rapidly Progressive Osteolysis and a Large Cystic Lesion that Destroyed the Inner Table of the Iliac Bone Following Cementless Total Hip Arthroplasty: A Case Report.

We report a case of rapidly progressive osteolysis and a very large cystic lesion that destroyed the inner table of the iliac bone following cementless total hip arthroplasty (THA). A 59-year-old female patient developed left hip pain at 11 years after THA. Osteolysis surrounding the acetabular cup was pointed out. She was brought to our hospital by ambulance due to severe left hip pain at 12 years after THA. Computed tomography (CT) showed that a cystic lesion in the pelvic cavity had destroyed the inner table of the iliac bone. Magnetic resonance imaging (MRI) showed a high signal intensity area of the hemorrhagic cystic lesion in the iliac bone in both T1-weighted and T2-weighted images. She underwent a liner and femoral head exchange, and required bone grafting and revision of the cup. The cystic lesion was removed and block-like allograft bone grafts were stuffed into the bone defects. If osteolysis and cystic lesions occur at the same time, not only the bone area around the implant but also a distant area like the inner table of the iliac bone may be destroyed. Additional tests such as CT or MRI may be useful to detect the presence of distant or cystic lesions. Early diagnosis and treatment are important because severe complications may occur in cases where osteolysis and cystic lesions coexist after THA.

Analyzing attempt and success factors for amputated digit replantation in Japan using the diagnosis procedure combination database.

The number of amputated finger replantation has declined in the USA and Germany in recent years; however, there have been no reports on recent trends in Japan. We examined the current practices, attempts, and success factors of digit replantation in Japan. We hypothesized that the rates of digit replantation and success rates were consistently standardized in Japan. The diagnosis procedure combination database was used to analyze 14004 cases from April 2014 to March 2020, excluding multiple-digit amputations, thus focusing on 13484 patients. We evaluated replantation success rates and identified factors influencing replantation decisions using multiple logistic regression analysis. The key findings included a higher frequency of replantation in thumb cases and surgeries during overtime hours, on Sundays, and in educational institutions. Success rates were notably higher for thumb replantations and patients under 20 years of age. Patients over 65 years of age treated with urokinase showed higher failure rates, unrelated to regional or hospital case volumes. The number of amputated digit replantation surgeries in Japan was high during overtime hours, on Sundays, and in educational institutions. Region, hospital type, and hospital case volume were not associated with a low success rate across Japan.

Potential of Continuous Local Antibiotic Perfusion Therapy for Fracture-Related Infections.

INTRODUCTION: Fracture-related infections (FRIs) are challenging for orthopedic surgeons, as conventional surgical treatment and systemic antimicrobial therapy cannot completely control local infections. Continuous local antibiotic perfusion (CLAP) is a novel and innovative therapy for bone and soft-tissue infections, and is expected to eradicate biofilms by maintaining a sustained high concentration of antimicrobial agents at the infected site. If CLAP therapy can eradicate infection even in cases with implants while preserving the implants, it would be an ideal and effective treatment for local refractory infections. This study aimed to evaluate the usefulness of novel CLAP therapy for FRIs. METHODS: Nine patients treated with CLAP therapy were retrospectively analyzed. The mean age was 65.9 (43-82) years, and the mean follow-up period was 14.9 (6-45) months. In all cases, the infected sites were related to the lower extremities (tibia, n = 6; fibula, n = 1; hip joint, n = 1; foot, n = 1). All patients underwent similar procedures for this therapy combined with negative-pressure wound therapy after thorough irrigation and debridement of infected tissues. RESULTS: The pathogens identified were Staphylococcus aureus (methicillin-resistant S. aureus, n = 5; methicillin-susceptible S. aureus, n = 1), Pseudomonas aeruginosa (n = 3), Enterococcus faecalis (n = 2), Corynebacterium (n = 1), and Enterobacter (n = 1); pathogens were not detected in one case. The mean duration of CLAP was 17.0 (7-35) days. In all cases, implants were preserved until bone union was achieved. Five cases relapsed; however, infection was finally suppressed in all cases by repeating this method. No side effects were observed. CONCLUSION: This novel case series presents treatment outcomes using CLAP therapy for FRIs. This method has the potential to control the infection without removing the implants, because of the sustained high concentration of antimicrobial agents at the infected site, and could be a valuable treatment option for refractory FRIs with implants, in which bone union has not been achieved.