The aim of this study was to develop a single-layer hybrid organic-inorganic sol-gel coating that is capable of a controlled antibiotic release for cementless hydroxyapatite (HA)-coated titanium orthopaedic prostheses. Coatings containing gentamicin at a concentration of 1.25% weight/volume (wt/vol), similar to that found in commercially available antibiotic-loaded bone cement, were prepared and tested in the laboratory for: kinetics of antibiotic release; activity against planktonic and biofilm bacterial cultures; biocompatibility with cultured mammalian cells; and physical bonding to the material (n = 3 in all tests). The sol-gel coatings and controls were then tested in vivo in a small animal healing model (four materials tested; n = 6 per material), and applied to the surface of commercially pure HA-coated titanium rods.Aims
Methods
Removal of infected components and culture-directed antibiotics are important for the successful treatment of chronic periprosthetic joint infection (PJI). However, as many as 27% of chronic PJI patients yield negative culture results. Although culture negativity has been thought of as a contraindication to one-stage revision, data supporting this assertion are limited. The aim of our study was to report on the clinical outcomes for one-stage and two-stage exchange arthroplasty performed in patients with chronic culture-negative PJI. A total of 105 consecutive patients who underwent revision arthroplasty for chronic culture-negative PJI were retrospectively evaluated. One-stage revision arthroplasty was performed in 30 patients, while 75 patients underwent two-stage exchange, with a minimum of one year's follow-up. Reinfection, re-revision for septic and aseptic reasons, amputation, readmission, mortality, and length of stay were compared between the two treatment strategies.Aims
Methods
Patients with infected arthroplasties are normally
treated with a two-stage exchange procedure using polymethylmethacrylate
bone cement spacers impregnated with antibiotics. However, spacers
may act as a foreign body to which micro-organisms may adhere and
grow. In this study it was hypothesised that subclinical infection may
be diagnosed with sonication of the surface biofilm of the spacer.
The aims were to assess the presence of subclinical infection through
sonication of the spacer at the time of a second-stage procedure,
and to determine the relationship between subclinical infection
and the clinical outcome. Of 55 patients studied, 11 (20%) were
diagnosed with subclinical infection. At a mean follow-up of 12
months (interquartile range 6 to 18), clinical failure was found in
18 (32.7%) patients. Of the patients previously diagnosed with subclinical
infection, 63% (7 of 11) had failed compared with 25% (11 of 44)
of those without subclinical infection (odds ratio 5.25, 95% confidence
interval 1.29 to 21.4, p = 0.021). Sonication of the biofilm of
the surface of the spacer is useful in order to exclude subclinical infection
and therefore contributes to improving the outcome after two-stage
procedures.