Periprosthetic joint infection (PJI) is a difficult complication requiring a comprehensive eradication protocol. Cure rates have essentially stalled in the last two decades, using methods of antimicrobial cement joint spacers and parenteral antimicrobial agents. Functional spacers with higher-dose antimicrobial-loaded cement and antimicrobial-loaded calcium sulphate beads have emphasized local antimicrobial delivery on the premise that high-dose local antimicrobial delivery will enhance eradication. However, with increasing antimicrobial pressures, microbiota have responded with adaptive mechanisms beyond traditional antimicrobial resistance genes. In this review we describe adaptive resistance mechanisms that are relevant to the treatment of PJI. Some mechanisms are well known, but others are new. The objective of this review is to inform clinicians of the known adaptive resistance mechanisms of microbes relevant to PJI. We also discuss the implications of these adaptive mechanisms in the future treatment of PJI. Cite this article: Bone Joint J 2022;104-B(5):575–580

Aims. The diagnosis of periprosthetic joint infection can be difficult due to the high rate of culture-negative infections. The aim of this study was to assess the use of next-generation sequencing for detecting organisms in synovial fluid. Materials and Methods. In this prospective, single-blinded study, 86 anonymized samples of synovial fluid were obtained from patients undergoing aspiration of the hip or knee as part of the investigation of a periprosthetic infection. A panel of synovial fluid tests, including levels of C-reactive protein, human neutrophil elastase, total neutrophil count, alpha-defensin, and culture were performed prior to next-generation sequencing. Results. Of these 86 samples, 30 were alpha-defensin-positive and culture-positive (Group I), 24 were alpha-defensin-positive and culture-negative (Group II) and 32 were alpha-defensin-negative and culture-negative (Group III). Next-generation sequencing was concordant with 25 results for Group I. In four of these, it detected antibiotic resistant bacteria whereas culture did not. In another four samples with relatively low levels of inflammatory biomarkers, culture was positive but next-generation sequencing was negative. A total of ten samples had a positive next-generation sequencing result and a negative culture. In five of these, alpha-defensin was positive and the levels of inflammatory markers were high. In the other five, alpha-defensin was negative and the levels of inflammatory markers were low. While next-generation sequencing detected several organisms in each sample, in most samples with a higher probability of infection, there was a predominant organism present, while in those presumed not to be infected, many organisms were identified with no predominant organism. Conclusion. Pathogens causing periprosthetic infection in both culture-positive and culture-negative samples of synovial fluid could be identified by next-generation sequencing. Cite this article: Bone Joint J 2018;100-B:127–33

Periprosthetic joint infection (PJI) is one of the most feared and challenging complications following total knee arthroplasty. We provide a detailed description of our current understanding regarding the management of PJI of the knee, including diagnostic aids, pre-operative planning, surgical treatment, and outcome. Cite this article: Bone Joint J 2015;97-B(10 Suppl A):20–9

The recently published Prophylactic Antibiotic Regimens In Tumor Surgery (PARITY) trial found no benefit in extending antibiotic prophylaxis from 24 hours to five days after endoprosthetic reconstruction for lower limb bone tumours. PARITY is the first randomized controlled trial in orthopaedic oncology and is a huge step forward in understanding antibiotic prophylaxis. However, significant gaps remain, including questions around antibiotic choice, particularly in the UK, where cephalosporins are avoided due to concerns of Clostridioides difficile infection. We present a review of the evidence for antibiotic choice, dosing, and timing, and a brief description of PARITY, its implication for practice, and the remaining gaps in our understanding.

Cite this article: Bone Joint J 2023;105-B(8):850–856.

Antibiotic resistance represents a threat to human health. It has been suggested that by 2050, antibiotic-resistant infections could cause ten million deaths each year. In orthopaedics, many patients undergoing surgery suffer from complications resulting from implant-associated infection. In these circumstances secondary surgery is usually required and chronic and/or relapsing disease may ensue. The development of effective treatments for antibiotic-resistant infections is needed. Recent evidence shows that bacteriophage (phages; viruses that infect bacteria) therapy may represent a viable and successful solution. In this review, a brief description of bone and joint infection and the nature of bacteriophages is presented, as well as a summary of our current knowledge on the use of bacteriophages in the treatment of bacterial infections. We present contemporary published in vitro and in vivo data as well as data from clinical trials, as they relate to bone and joint infections. We discuss the potential use of bacteriophage therapy in orthopaedic infections. This area of research is beginning to reveal successful results, but mostly in nonorthopaedic fields. We believe that bacteriophage therapy has potential therapeutic value for implant-associated infections in orthopaedics.

Cite this article: Bone Joint J 2021;103-B(2):234–244.