Aseptic versus septic revision total knee arthroplasty: Patient satisfaction, outcome and quality of life improvement

10.1016/j.knee.2009.09.001Knee173200-203KNEE

Patellar management in revision total knee arthroplasty. Is patellar resurfacing a better option?

10.1016/j.arth.2009.04.009Journal of Arthroplasty254589-593JOAR

Factors influencing local control in patients undergoing breast conservation surgery for ductal carcinoma in situ

Background: The aim of our study was to assess various predictors for local recurrence (LR) in patients undergoing breast conservation surgery (BCS) for ductal carcinoma in situ (DCIS).Materials and methods: An audit was performed of 582 consecutive patients with DCIS between Jan 1975 to June 2008. In patients undergoing BCS, local guidelines reported a margin of ≥10 mm during the above period. Guideline with regard to margin of excision changes soon after this period. We retrospectively analysed clinical and pathological risk factors for local recurrence in patients undergoing BCS. Statistical analysis was carried out using SPSS version 19, and a cox regression model for multivariate analysis of local recurrence was used.Results: Overall 239 women had BCS for DCIS during the above period. The actuarial 5-year recurrence rate was 9.6%. The overall LR rate was 17% (40/239. LR was more common in patients less or equal 50 years: (10/31 patients, 32%) compared to patients > 50 years (30/208, 14%, P = 0.02). Forty three per cent of patients (6/14) with less than 5 mm margin developed LR which was significantly higher compared to patients with 5–9 mm margin (12%, 3/25) and with ≥10 mm margin (14%, 27/188, P = 0.01). On multivariate analysis age less or equal 50 years, less than 5 mm pathological margin were independent prognostic factors for local recurrence.Conclusion: Our study shows that younger age (less or equal 50 years) and a margin less than 5 mm are poor prognostic factors for LR in patients undergoing breast conservation surgery for DCIS

Design optimization of a novel vertical augmentation channel housing a cross - flow turbine and performance evaluation as a wave energy converter

A novel vertical augmentation channel housing a direct-drive cross-flow turbine, with nozzles on both the sides of the turbine, was designed and an optimized configuration was obtained. The geometries of the guide nozzle and the front nozzle were optimized under steady flow conditions. The performance of the cross-flow turbine was analyzed using commercial computational fluid dynamics (CFD) code ANSYS-CFX. The optimized design was then evaluated as a wave energy converter both experimentally and computationally. The waves in the numerical wave tank (NWT) were generated using a piston type wave-maker. The optimized design gave a maximum output power of 13.2 W and an efficiency of 48.31% at a wave height of 0.2 m and wave period of 2.75 s for a rotational speed of 35 rpm. The difference between numerical and experimental efficiencies was within 3.5%. In addition to this, particle imagery velocimetry was used to study the flow characteristics in the augmentation channel and the turbine. The results show that the CFD code captures the flow in the augmentation channel and around the turbine accurately. The optimized design, which occupies less space than other wave energy converters, can be used to efficiently harness energy from the waves