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
Currently, there is no animal model in which
to evaluate the underlying physiological processes leading to the heterotopic
ossification (HO) which forms in most combat-related and blast wounds.
We sought to reproduce the ossification that forms under these circumstances
in a rat by emulating patterns of injury seen in patients with severe
injuries resulting from blasts. We investigated whether exposure
to blast overpressure increased the prevalence of HO after transfemoral
amputation performed within the zone of injury. We exposed rats
to a blast overpressure alone (BOP-CTL), crush injury and femoral
fracture followed by amputation through the zone of injury (AMP-CTL)
or a combination of these (BOP-AMP). The presence of HO was evaluated
using radiographs, micro-CT and histology. HO developed in none
of nine BOP-CTL, six of nine AMP-CTL, and in all 20 BOP-AMP rats.
Exposure to blast overpressure increased the prevalence of HO. This model may thus be used to elucidate cellular and molecular
pathways of HO, the effect of varying intensities of blast overpressure,
and to evaluate new means of prophylaxis and treatment of heterotopic
ossification. Cite this article:
