Clinical experience indicates the beneficial effects of antibiotic-loaded bone cement. Although in vitro studies have shown the formation of a biofilm on its surface they have not considered the gap between the cement and the bone. We have investigated bacterial survival in that gap. Samples with gaps 200 μm wide were made of different bone cements. These were stored dry (‘pre-elution’) or submersed in phosphate-buffered saline to simulate the initial release of gentamicin (‘post-elution’). The gaps were subsequently inoculated with bacteria, which had been isolated from infected orthopaedic prostheses and assessed for their sensitivity to gentamicin. Bacterial survival was measured 24 hours after inoculation. All the strains survived in plain cements. In the pre-elution gentamicin-loaded cements only the most gentamicin-resistant strain, CN5115, survived, but in post-elution samples more strains did so, depending on the cement tested. Although high concentrations of gentamicin were demonstrated in the gaps only the gentamicin-sensitive strains were killed. This could explain the increased prevalence of gentamicin-resistant infections which are seen clinically.

There has been an increase in the incidence of bone and joint tuberculosis (BJTB) in The Netherlands and we have carried out an epidemiological study in order to find an explanation for this increase. Data from 1993 to 2000 from The Netherlands Tuberculosis Register (NTR) were used. In 1993 there was a total of 52 patients with BJTB. This figure increased gradually to 80 in 1999 before decreasing to 61 in 2000.

There was a total of 12 447 patients with tuberculosis; BJTB was found in 532, accounting for 4.3% of all cases and 10.6% of all extrapulmonary cases. Localisation in the spine occurred in 56%.

Certain immigrants, in particular from Somalia, were more likely to have BJTB than other immigrants or the native Dutch population. Increased age and female gender were associated with BJTB. Only 15% of BJTB patients also suffered from pulmonary tuberculosis. The usual long delay in the diagnosis of BJTB may be shortened if physicians are more aware of tuberculosis.

We studied retrospectively the outcome of patellofemoral arthroplasty (PFA) using the Richards prosthesis in 51 patients (56 knees). Their mean age was 50 years (30 to 77). In 43 patients (45 knees), the American Knee Society score and the patients’ subjective judgement were assessed. Excellent or good results were obtained in 86% of cases at a mean follow-up of 17 years (15 to 21).

Because of ongoing tibiofemoral osteoarthritis, two patients required a high tibial osteotomy and ten PFAs were converted to a total knee arthroplasty after a mean of 15.6 years (10 to 21). The PFAs were stable during follow-up with a loosening rate of only 2%.

We conclude that a patellofemoral prosthesis is a good treatment option with successful long-term results in middle-aged patients with radiologically documented, isolated, patellofemoral osteoarthritis.