The best management of displaced intracapsular femoral neck fractures in the elderly remains undecided. Most are treated by hemiarthroplasty. The aim of this study was to establish whether the advantages of cement outweigh the disadvantages.

All patients with displaced intracapsular femoral neck fractures treated with herniarthroplasty between January 1997 and May 1998, in 2 hospitals within the same Deanery, were reviewed. The same prosthesis was used, but in hospital A they were uncemented, and in B cemented. There were 122 patients in hospital A and 123 in B. We conducted a detailed retrospective analysis of hospital notes. All surviving patients (50 and 56 respectively) were interviewed to obtain pre-fracture and current scores of pain, walking ability, use of walking aids, activities of daily living (ADL) and accommodation status, using validated scoring systems. The relative deterioration over the follow-up period (32–36 months) was determined and the groups compared.

Patient demographics confirmed comparability of groups. There was no greater incidence of intra-operative fall in diastolic blood pressure, or oxygen saturation in the cemented group. Cemented procedures were on average 15 minutes longer. Median in-patient stay was the same. Significantly fewer of the cemented group had been revised or were awaiting revision (p=0. 036). There was no difference in mortality rates at any point between surgery and follow-up. Prospective assessment of surviving patients revealed highly statistically significant greater deterioration in pain (p=0. 003), walking ability (p=0. 002), use of walking aids (p=0. 003) and ADL (p=0. 009) in the uncemented group. The trend for more dependent accommodation in the uncemented group failed to reach statistical significance (p=0. 14).

In conclusion, the cemented group faired significantly better than the uncemented group. Our findings suggest the advantages of cement outweigh the disadvantages, and we support the use of cemented hemiarthroplasty for the displaced intracapsular femoral neck fracture in the elderly patient.

Differentiating cases of aseptic loosening of total hip arthroplasty (THA) from loosening due to low-grade infection can often be difficult. It is possible that some cases of ‘aseptic’ loosening may be related to unidentified bacterial infection.

Using Polymerase Chain Reaction (PCR), this study attempted to identify the frequency with which bacterial DNA could be observed at revision arthroplasty for what was considered ‘aseptic’ loosening.

All revision cases had to fulfil strict criteria to be considered aseptically loose In all cases operative specimens from the synovial fluid, synovium, femoral and acetabular membranes where possible were sent for analysis by histology, bacteriology and by PCR to identify the presence of the 16S bacterial ribosomal fraction, an indicator of bacterial DNA. Ten bacteria per millilitre of tissue/fluid were the threshold for detection. As a control for environmental contamination, specimens from primary THA were also sent for analysis in the same manner as revisions.

The identification of bacterial DNA in at least one sample from a patient was considered a positive case result.

45 revision THA were identified over a 3-year period (1998–2001). From those 45 revision cases, 163 specimens were sent for analysis by PCR. These specimens were compared to the control group of 34 primary THA from which 91 specimens were sent for analysis by PCR. When analysed by specimens positive by PCR, bacterial DNA was identified in 55 of 163 specimens sent from the 45 revision THA. This compared with 21 of 91 specimens positive by PCR sent from the 34 primary THA (p=0. 07).

When analysed by cases positive by PCR, bacterial DNA was identified in 29 of 45 revision THA and in 8 of 34 primary THA (p< 0. 001).

PCR is a sensitive test for detecting infection in revision THA. Results from the primary THA cases would suggest there is at least a 23% false positive rate even with negative bacterial culture. The increased frequency with which bacterial DNA has been identified in ‘aseptically’ loose revision THAs, however, is unlikely to be due solely to environmental contamination. These results may have relevance for our interpretation and understanding of aseptic loosening as well for the diagnosis of prosthetic infection.

Introduction: Aseptic loosening of THR has a multifactorial aetiology. Differentiating such cases from loosening due to low-grade infection can often be difficult. It is possible that at least some cases of ‘aseptic’ loosening may be related to unidentified bacterial infection. This study attempted to identify the frequency with which bacterial DNA could be observed in the periprosthetic membrane and synovial fluid of patients undergoing revision surgery for what was considered ‘aseptic’ loosening.

Methods: Specimens from 39 revision and 31 primary hip replacements were obtained. The latter were used as a control for environmental contamination. All revision THR cases were investigated pre-operatively for infection by CRP, ESR, WCC, Gallium Scan. Operative specimens were analysed by bacteriological culture as well as by PCR to identify the presence of the 16S bacterial ribosomal fraction. Results were analysed by Chi square test.

Results: By PCR, bacterial DNA was identified in 22 of 39 revision hip surgery specimens and 6 of 31 primary hip replacement specimens (p=0.002). By culture none of these specimens had any bacterial growth.

Conclusions: The increased frequency with which bacterial DNA has been identified in ‘aseptically’ loose revision THR is unlikely to be due solely to environmental contamination although this remains a concern. These results may have relevance for our interpretation and understanding of aseptic loosening as well for the diagnosis of prosthetic infection.