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![Research paper thumbnail of [Modern three-piece total ankle replacement. Frequency and causes of luxation and premature wear of the polyethylene bearing]](https://attachments.academia-assets.com/50332943/thumbnails/1.jpg)
](Der Orthopäde, 2007
Luxation and excessive wear of the mobile bearing in modern three-piece total ankle replacement (... more Luxation and excessive wear of the mobile bearing in modern three-piece total ankle replacement (TAR) is reported. We conducted a systematic review of studies to explore and discuss the rate and causes of these complications.A systematic review of studies since 2000 showed 26 studies with altogether 1,318 followed up TARs which we analyzed. Of these 1,318 TARs, 188 (14.3%) were revised and 56 (4.2%) complications with the mobile bearing were reported. A total of 39 cases (3%), i.e., 20.7% of all revisions, were revised due to failure of the mobile bearing, including 17 cases with subluxation (1.3%), 15 with asymmetric load of the bearing (1.1%), 10 with fracture of the polyethylene (PE) inlay (0.76%), 7 with massive PE wear (0.53%), and 7 with luxation of the meniscal bearing (0.53%).Complications due to the meniscal mobile bearing in TARs such as luxation, subluxation, massive wear, and fracture of the PE inlay are rare complications. The cause of these complications is regularly n...
IEEE Transactions on Power Apparatus and Systems, 1968
The design, the implementation of, and the operating experience with a large-scale digital comput... more The design, the implementation of, and the operating experience with a large-scale digital computer system used for optimum scheduling and on-line control of a complex hydro-thermal electric utility system is discussed. Dispatch techniques are outlined which produce optimal scheduling of steam, stored hydro, pumped hydro, and run-of-river hydro generation and economy interchange over a 32-hour period with full consideration given
IEEE Transactions on Industry and General Applications, 1969
Now that development of brushless excitation has overcome the brush sparking and slip ring mainte... more Now that development of brushless excitation has overcome the brush sparking and slip ring maintenance problem, industry can use large horsepower synchronous motors on its drives. These motors offer advantages in low starting currents with high starting torques, and the ability to supply reactive kVA to the plant system if desired.
IEEE Transactions on Industry Applications, 2000
Mill drives for the cement industry have rapidly increased in horsepower during the past few year... more Mill drives for the cement industry have rapidly increased in horsepower during the past few years. There appears to be no limit in size. Because of this increase in horsepower, the application problems have become more complex. The usual type of mill drives may not provide the optimum performance and cost. Nonconventional drives should be included in the evaluation. The
IEEE Transactions on Industry Applications, 2000
Contemporary Security Policy, 1999
... Gordon Craig, for example, views the entire history of the German nation in the nineteenth an... more ... Gordon Craig, for example, views the entire history of the German nation in the nineteenth and twentieth centuries as 'one long constitutional struggle',5 in which the army played a crucial role in 'determining the political destiny of the nation' .6 The role of the military in the ...
Der Orthopäde, 2007
Luxation and excessive wear of the mobile bearing in modern three-piece total ankle replacement (... more Luxation and excessive wear of the mobile bearing in modern three-piece total ankle replacement (TAR) is reported. We conducted a systematic review of studies to explore and discuss the rate and causes of these complications.A systematic review of studies since 2000 showed 26 studies with altogether 1,318 followed up TARs which we analyzed. Of these 1,318 TARs, 188 (14.3%) were revised and 56 (4.2%) complications with the mobile bearing were reported. A total of 39 cases (3%), i.e., 20.7% of all revisions, were revised due to failure of the mobile bearing, including 17 cases with subluxation (1.3%), 15 with asymmetric load of the bearing (1.1%), 10 with fracture of the polyethylene (PE) inlay (0.76%), 7 with massive PE wear (0.53%), and 7 with luxation of the meniscal bearing (0.53%).Complications due to the meniscal mobile bearing in TARs such as luxation, subluxation, massive wear, and fracture of the PE inlay are rare complications. The cause of these complications is regularly n...
IEEE Transactions on Power Apparatus and Systems, 1968
The design, the implementation of, and the operating experience with a large-scale digital comput... more The design, the implementation of, and the operating experience with a large-scale digital computer system used for optimum scheduling and on-line control of a complex hydro-thermal electric utility system is discussed. Dispatch techniques are outlined which produce optimal scheduling of steam, stored hydro, pumped hydro, and run-of-river hydro generation and economy interchange over a 32-hour period with full consideration given
IEEE Transactions on Industry and General Applications, 1969
Now that development of brushless excitation has overcome the brush sparking and slip ring mainte... more Now that development of brushless excitation has overcome the brush sparking and slip ring maintenance problem, industry can use large horsepower synchronous motors on its drives. These motors offer advantages in low starting currents with high starting torques, and the ability to supply reactive kVA to the plant system if desired.
IEEE Transactions on Industry Applications, 2000
Mill drives for the cement industry have rapidly increased in horsepower during the past few year... more Mill drives for the cement industry have rapidly increased in horsepower during the past few years. There appears to be no limit in size. Because of this increase in horsepower, the application problems have become more complex. The usual type of mill drives may not provide the optimum performance and cost. Nonconventional drives should be included in the evaluation. The
IEEE Transactions on Industry Applications, 2000
Contemporary Security Policy, 1999
... Gordon Craig, for example, views the entire history of the German nation in the nineteenth an... more ... Gordon Craig, for example, views the entire history of the German nation in the nineteenth and twentieth centuries as 'one long constitutional struggle',5 in which the army played a crucial role in 'determining the political destiny of the nation' .6 The role of the military in the ...