Three Staged Revision Arthroplasty Using Structural Allograft in Chronic Periprosthetic Joint Infection Accompanied by Fracture: A Case Report

Revision arthroplasty for chronic periprosthetic joint infection is complex and determined by many variables. Generally, two-staged revision arthroplasty is the standard treatment for the management of chronic periprosthetic joint infection. However, it is difficult to resolve chronic infection accompanied by large bone deficiency due to pathologic fracture. I report a case of successful three-staged revision arthroplasty using frozen structural allograft in chronic periprosthetic knee joint infection accompanied by extensive bone defect due to fracture.

Immunity status in patients with periprosthetic knee joint infection

Implant-associated infection is one of the most severe complications after total replacement of larger joints. The diagnosis of periprosthetic infection are often impeded as 5-34% of bacteriological tests are false-negative. Now the investigations of the immune status of patients suspected of periprosthetic infection are considered perspective as these are aimed at finding the most significant indicators for underlying the diagnosis of this pathology. In this research, we assessed immunology indicators in peripheral blood of patients with periprosthetic infection in their knee joints. We determined immunology characteristics associated with the clinical aspects of the progressing pathology. Our findings can be used as the basis for further search of pathophysiological mechanisms of periprosthetic infection progress in the knee joint as well as defining new diagnostic approaches.Reviewers:Ivanov A.N., MD, DSc;Prof. Puchinyan D.M., MD, DSc

Improving outcomes in acute and chronic periprosthetic hip and knee joint infection with a multidisciplinary approach

Aims Periprosthetic hip and knee infection remains one of the most severe complications following arthroplasty, with an incidence between 0.5% to 1%. This study compares the outcomes of revision surgery for periprosthetic joint infection (PJI) following hip and knee arthroplasty prior to and after implementation of a specialist PJI multidisciplinary team (MDT). Methods Data was retrospectively analyzed from a single centre. In all, 29 consecutive joints prior to the implementation of an infection MDT in November 2016 were compared with 29 consecutive joints subsequent to the MDT conception. All individuals who underwent a debridement antibiotics and implant retention (DAIR) procedure, a one-stage revision, or a two-stage revision for an acute or chronic PJI in this time period were included. The definition of successfully treated PJI was based on the Delphi international multidisciplinary consensus. Results There were no statistically significant differences in patient demographics or comorbidities between the groups. There was also no significant difference in length of overall hospital stay (p = 0.530). The time taken for formal microbiology advice was significantly shorter in the post MDT group (p = 0.0001). There was a significant difference in failure rates between the two groups (p = 0.001), with 12 individuals (41.38%) pre-MDT requiring further revision surgery compared with one individual (6.67%) post-MDT inception. Conclusion Our standardized multidisciplinary approach for periprosthetic knee and hip joint infection shows a significant reduction in failure rates following revision surgery. Following implementation of our MDT, our success rate in treating PJI is 96.55%, higher than what current literature suggests. We advocate the role of a specialist infection MDT in the management of patients with a PJI to allow an individualized patient-centred approach and care plan, thereby reducing postoperative complications and failure rates. Cite this article: Bone Jt Open 2021;2(7):509–514.

Successful Treatment of Staphylococcus aureus Prosthetic Joint Infection with Bacteriophage Therapy

Successful joint replacement is a life-enhancing procedure with significant growth in the past decade. Prosthetic joint infection occurs rarely; it is a biofilm-based infection that is poorly responsive to antibiotic alone. Recent interest in bacteriophage therapy has made it possible to treat some biofilm-based infections, as well as those caused by multidrug-resistant pathogens, successfully when conventional antibiotic therapy has failed. Here, we describe the case of a 61-year-old woman who was successfully treated after a second cycle of bacteriophage therapy administered at the time of a two-stage exchange procedure for a persistent methicillin-sensitive Staphylococcus aureus (MSSA) prosthetic knee-joint infection. We highlight the safety and efficacy of both intravenous and intra-articular infusions of bacteriophage therapy, a successful outcome with a single lytic phage, and the development of serum neutralization with prolonged treatment.

Periprosthetic joint infection with Ureaplasma parvum detected by 16S rRNA PCR

Usual culture methods to identify pathogenic bacteria can be unsuccessful, particularly when working with fastidious organisms. We present a case of early periprosthetic knee joint infection with Ureaplasma parvum only identified using 16S ribosomal RNA PCR. This case represents the impact molecular methods of bacterial identification can have on clinical care allowing for more targeted antimicrobial therapy; something which is imperative in an era of increasing antimicrobial resistance.

Revision TKA with a distal femoral replacement is at high risk of reinfection after two-stage exchange for periprosthetic knee joint infection

Purpose Megaprosthetic distal femoral reconstruction (DFR) is a limb-salvage procedure to address bone loss following two-stage revision for periprosthetic knee joint infection (PJI). The purpose of this study was to analyze the survival of DFR compared to hinged total knee arthroplasty (TKA). It was hypothesized that DFR was associated with a poorer survival. Methods In this retrospective single-center study, 97 subjects who underwent two-stage revision of chronic knee PJI were included. Among these, 41 were DFR. The diagnosis of PJI was established using the Musculoskeletal Infection Society (MSIS) criteria. Implant survival was calculated using Kaplan–Meier method and compared with the log-rank test as well as multivariate Cox regression at a minimum follow-up period of 24 months. Results The median follow-up period was 59 (interquartile range (IQR) 45–78) months. Overall, 24% (23/97) of patients required revision surgery for infection. The infection-free survival of rotating hinge revision TKA was 93% (95% Confidence Interval (CI) 86–100%) at five years compared to 50% (95% CI 34–66%) for DFR. In multivariate analysis, the risk factors for reinfection were DFR reconstruction (HR 4.7 (95% CI 1–22), p = 0.048), length of megaprosthesis (HR 1.006 (95% CI 1.001–1.012), p = 0.032) and higher BMI (HR 1.066, 95% CI 1.018–1.116), p = 0.007). 10% (4/41) of patients undergoing DFR underwent amputation to treat recurrent infection. Conclusion Megaprosthetic DFR as part of a two-stage exchange for PJI is a salvage treatment that has a high risk for reinfection compared to non-megaprosthetic TKA. Patients must therefore be counseled accordingly. Level of evidence Retrospective observational study, Level IV.