Delayed postoperative inoculation of orthopaedic implants with persistent wound drainage or bacterial seeding of a haematoma can result in periprosthetic joint infection (PJI). The aim of this in vivo study was to compare the efficacy of vancomycin powder with vancomycin-eluting calcium sulphate beads in preventing PJI due to delayed inoculation. A mouse model of PJI of the knee was used. Mice were randomized into groups with intervention at the time of surgery (postoperative day (POD) 0): a sterile control (SC; n = 6); infected control (IC; n = 15); systemic vancomycin (SV; n = 9); vancomycin powder (VP; n = 21); and vancomycin bead (VB; n = 19) groups. Delayed inoculation was introduced during an arthrotomy on POD 7 with 1 × 105 colony-forming units (CFUs) of a bioluminescent strain of Aims
Methods
Peri-prosthetic osteolysis and subsequent aseptic
loosening is the most common reason for revising total hip replacements.
Wear particles originating from the prosthetic components interact
with multiple cell types in the peri-prosthetic region resulting
in an inflammatory process that ultimately leads to peri-prosthetic
bone loss. These cells include macrophages, osteoclasts, osteoblasts
and fibroblasts. The majority of research in peri-prosthetic osteolysis
has concentrated on the role played by osteoclasts and macrophages.
The purpose of this review is to assess the role of the osteoblast
in peri-prosthetic osteolysis. In peri-prosthetic osteolysis, wear particles may affect osteoblasts
and contribute to the osteolytic process by two mechanisms. First,
particles and metallic ions have been shown to inhibit the osteoblast
in terms of its ability to secrete mineralised bone matrix, by reducing
calcium deposition, alkaline phosphatase activity and its ability
to proliferate. Secondly, particles and metallic ions have been
shown to stimulate osteoblasts to produce
The use of journal clubs and, more recently,
case-based discussions in order to stimulate debate among orthopaedic
surgeons lies at the heart of orthopaedic training and education. A
virtual learning environment can be used as a platform to host virtual
journal clubs and case-based discussions. This has many advantages
in the current climate of constrained time and diminishing trainee
and consultant participation in such activities. The virtual environment
model opens up participation and improves access to journal clubs
and case-based discussions, provides reusable educational content,
establishes an electronic record of participation for individuals,
makes use of multimedia material (including clinical imaging and
photographs) for discussion, and finally, allows participants to
link case-based discussions with relevant papers in the journal
club. The Leicester experience highlights the many advantages and some
of the potential difficulties in setting up such a virtual system
and provides useful guidance for those considering such a system
in their own training programme. As a result of the virtual learning
environment, trainee participation has increased and there is a
trend for increased consultant input in the virtual journal club
and case-based discussions. It is likely that the use of virtual environments will expand
to encompass newer technological approaches to personal learning
and professional development.
