Peri-prosthetic fracture after joint replacement in the lower limb is associated with significant morbidity. The primary aim of this study was to investigate the incidence of peri-prosthetic fracture after total hip replacement (THR) and total knee replacement (TKR) over a ten-year period using a population-based linked dataset. Between 1 April 1997 and 31 March 2008, 52,136 primary THRs, 8726 revision THRs, 44,511 primary TKRs, and 3222 revision TKRs were performed. Five years post-operatively, the rate of fracture was 0.9% after primary THR, 4.2% after revision THR, 0.6% after primary TKR and 1.7% after revision TKR. Comparison of survival analysis for all primary and revision arthroplasties showed peri-prosthetic fractures were more likely in females, patients aged > 70 and after revision arthroplasty. Female patients aged > 70 should be warned of a significantly increased risk of peri-prosthetic fracture after hip or knee replacement. The use of adjuvant medical treatment to reduce the effect of peri-prosthetic osteoporosis may be a direction of research for these patients.

Background and purpose Total elbow replacement (TER) is used in the treatment of inflammatory arthropathy, osteoarthritis, and posttraumatic arthrosis, or as the primary management for distal humeral fractures. We determined the annual incidence of TER over an 18-year period. We also examined the effect of surgeon volume on implant survivorship and the rate of systemic and joint-specific complications.Methodology We examined a national arthroplasty register and used linkage with national hospital episode statistics, and population and mortality data to determine the incidence of complications and implant survivorship.Results There were 1,146 primary TER procedures (incidence: 1.4 per 105 population per year). The peak incidence was seen in the eighth decade and TER was most often performed in females (F:M ratio = 2.9:1). The primary indications for surgery were inflammatory arthropathy (79%), osteoarthritis (9%), and trauma (12%). The incidence of TER fell over the period (r = –0.49; p = 0.037). This may be due to a fall in the number of procedures performed for inflammatory arthropathy (p < 0.001). The overall 10-year survivorship was 90%. Implant survival was better if the surgeon performed more than 10 cases per year.Interpretation The prevalence of TER has fallen over 18 years, and implant survival rates are better in surgeons who perform more than 10 cases per year. A strong argument can be made for a managed clinic network for total elbow arthroplasty.

We undertook a study to determine the rates of infection and revision of total knee replacement (TKR) in patients with renal failure, renal transplantation and those undergoing renal dialysis in Scotland. The overall early and late infection rates were 1.10% and 2.19% compared with 1.06% and 2.01%, respectively, for non-renal patients. Patients with renal failure had a significantly increased risk of early infection (1.6%, relative risk 1.52, p = 0.002) and late infection (4.47%, relative risk 2.22, p < 0.001). Those on renal dialysis had significantly increased risks of late infection (8.03%, relative risk 3.99, p < 0.001) and early revision (3.70%, relative risk 4.40, p < 0.001). Renal transplant patients had a significantly increased risk of late infection, regardless of whether renal transplantation occurred before TKR (9.09%, relative risk 4.517, p = 0.027) or at any time (8.0%, relative risk 3.975, p = 0.047). There were significantly increased rates of comorbidities associated with infection for all the renal patient groups. Logistic regression analysis showed that renal failure and renal dialysis were independent risk factors for early infection and revision, respectively.

We describe a set of methods to enable fully automated analysis of a novel label-free spinning-disc format microarray system. This microarray system operates in a dual-channel mode, simultaneously acquiring fluorescence as well as interferometric signals. The label-free interferometric component enables the design of robust gridding methods, which account for rotational effects difficult to estimate in traditional microarray image analysis. Printing of microarray features in a Cartesian grid is preferable for commercial systems because of the benefits of using existing DNA/protein printing technologies. The spinning disc operation of the microarray requires spatial transformation of Cartesian microarray features, from the reader/scanner frame of reference to the disc frame of reference. We describe a fast spatial transformation method with no measurable degradation in the quality of transformed data, for this purpose. The gridding method uses frequency-domain information to calculate grid spacing and grid rotation. An adaptive morphological segmentation method is used to segment microarray spots with variable sizes accurately. The entire process, from the generation of the raw data to the extraction of biologically relevant information, can be performed without any manual intervention, allowing for the deployment of high-throughput systems. These image analysis methods have enabled this microarray system to achieve superior sensitivity limits.