High rate of radiolucent lines following the cemented original design of the ATTUNE total knee arthroplasty

Aims Loosening of components after total knee arthroplasty (TKA) can be associated with the development of radiolucent lines (RLLs). The aim of this study was to assess the rate of formation of RLLs in the cemented original design of the ATTUNE TKA and their relationship to loosening. Methods A systematic search was undertaken using the Cochrane methodology in three online databases: MEDLINE, Embase, and CINAHL. Studies were screened against predetermined criteria, and data were extracted. Available National Joint Registries in the Network of Orthopaedic Registries of Europe were also screened. A random effects model meta-analysis was undertaken . Results Of 263 studies, 12 were included with a total of 3,861 TKAs. Meta-analysis of ten studies showed high rates of overall tibial or femoral RLLs for the cemented original design of the ATTUNE TKA. The overall rate was 21.4% (95% confidence interval (CI) 12.7% to 33.7%) for all types of design but was higher for certain subgroups: 27.4% (95% CI 13.4% to 47.9%) for the cruciate-retaining type, and 29.9% (95% CI 15.6% to 49.6%) for the fixed-bearing type. Meta-analysis of five studies comparing the ATTUNE TKA with other implants showed a significantly higher risk of overall tibial or femoral RLLs (odds ratio (OR) 2.841 (95% CI 1.219 to 6.623); p = 0.016) for the ATTUNE. The rates of loosening or revision for loosening were lower, at 1.2% and 0.9% respectively, but the rates varied from 0% to 16.3%. The registry data did not report specifically on the original ATTUNE TKA or on revision due to loosening, but ‘all-cause’ five-year revision rates for the cemented ATTUNE varied from 2.6% to 5.9%. Conclusion The original cemented ATTUNE TKA has high rates of RLLs, but their clinical significance is uncertain given the overall low associated rates of loosening and revision. However, in view of the high rates of RLLs and the variation in the rates of loosening and revision between studies and registries, close surveillance of patients who have undergone TKA with the original ATTUNE system is recommended

Local Treatment of Experimental Pseudomonas aeruginosa Osteomyelitis with a Biodegradable Dilactide Polymer Releasing Ciprofloxacin▿

A biodegradable system of poly-d,l-dilactide releasing ciprofloxacin was assessed in a Pseudomonas aeruginosa osteomyelitis model after inoculation of the test pathogen into the left tibia of 76 New Zealand White rabbits; 31 were controls (group A), and 45 were implanted with the polymer at the infection site (group B). The rabbits were killed on a weekly basis, and cancellous bone was harvested for histopathology and for estimation of bacterial growth and the concentrations of ciprofloxacin. Tibial X ray was performed immediately before the animals were killed. The total number of fistulas with purulent discharge that developed after inoculation of the pathogen was counted, and fistulas with purulent discharge were found in 16 animals in group A (51.6%) and 3 animals in group B (6.7%) (P < 0.0001). The animals in group A had a profound loss of body weight compared to the animals in group B. The main radiological finding was the presence of sequestra in 25 animals (80.6%) in group A and 6 animals in group B (13.3%) (P < 0.0001). The bacterial load in group B was significantly reduced compared to that in group A, possibly due to the prolonged local antibiotic release at concentrations exceeding even 80 times the MIC for the test pathogen. The histology of animals killed after week 49 revealed a mild inflammatory reaction accompanied by diffuse fibrosis and new bone formation in group A animals and the presence of small polymer particles in group B animals. It is concluded that the system described achieved eradication of the pathogen, accompanied by clinical and radiologically confirmed benefits, so this treatment may be a candidate for the management of difficult orthopedic infections

Local treatment of experimental Pseudomonas aeruginosa osteomyelitis with a biodegradable dilactide polymer releasing ciprofloxacin

A biodegradable system of poly-D,L-dilactide releasing ciprofloxacin was assessed in a Pseudomonas aeruginosa osteomyelitis model after inoculation of the test pathogen into the left tibia of 76 New Zealand White rabbits; 31 were controls (group A), and 45 were implanted with the polymer at the infection site (group B). The rabbits were killed on a weekly basis, and cancellous bone was harvested for histopathology and for estimation of bacterial growth and the concentrations of ciprofloxacin. Tibial X ray was performed immediately before the animals were killed. The total number of fistulas with purulent discharge that developed after inoculation of the pathogen was counted, and fistulas with purulent discharge were found in 16 animals in group A (51.6%) and 3 animals in group B (6.7%) (P &lt; 0.0001). The animals in group A had a profound loss of body weight compared to the animals in group B. The main radiological finding was the presence of sequestra in 25 animals (80.6%) in group A and 6 animals in group B (13.3%) (P &lt; 0.0001). The bacterial load in group B was significantly reduced compared to that in group A, possibly due to the prolonged local antibiotic release at concentrations exceeding even 80 times the MIC for the test pathogen. The histology of animals killed after week 49 revealed a mild inflammatory reaction accompanied by difuse fibrosis and new bone formation in group A animals and the presence of small polymer particles in group B animals. It is concluded that the system described achieved eradication of the pathogen, accompanied by clinical and radiologically confirmed benefits, so this treatment may be a candidate for the management of difficult orthopedic infections