Our goal was to evaluate the objective and subjective midterm outcome after revision of a failed shoulder arthroplasty with a reverse design prosthesis. Twenty consecutive patients with 21 revisions of a primary shoulder arthroplasty using reverse shoulder prosthesis Delta III(®) were followed up postoperatively for a mean of 46 months including clinical and radiological examination. Complications were recorded and Constant score, DASH and SF36 were assessed. With the numbers given a significant reduction of pain was achieved from 8.7 to 3.0 (p < 0.001). There was a significant improvement of active flexion from 43° to 97° (p < 0.001) and active abduction from 44° to 90° (p < 0.001). However, at the same time, active external rotation with an adducted humerus decreased significantly from 26° to 12° (p = 0.012). The constant score improved significantly from 16.7 to 55.9 (p < 0.001). Sixteen patients (84%) rated their shoulder better or much better than before. In 43% an intraoperative and in 38% a postoperative complication occurred including two late stage infections which required prosthesis removal. Our results support the use of the reverse prosthesis as revision prosthesis. The reverse design helps to compensate functional deficits due to severe soft-tissue damage except active external rotation. Nevertheless, the revision is a technically demanding procedure reflected in a high rate of intraoperative complications. The rate of secondary infections of 10% remains a special concern.

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A retrospective analysis of the own patients treated with the described surgical technique was performed. On the basis of Kaplan-Meier survival analysis, it could be demonstrated that there is a correlation between the patients' level of activity and the long-term survival rate 10-15 years after the osteotomy. Moreover, the extent of correction has a direct influence on the long-term result.

Die Herstellung von Blechbauteilen umfasst mehrere Schneid- und Umformoperationen, welche die resultierenden Bauteileigenschaften beeinflussen. Daher weichen die Eigenschaften vom Ausgangszustand des Halbzeugs ab, was bei der Auslegung von Clinchverbindungen berücksichtigt werden muss. Durch die Vernetzung der Einzelverfahren auf Basis der Prozessdaten werden ein Vorgehen zur Ermittlung der Halbzeugeigenschaften beim Scherschneiden und die Auswirkungen auf die Verbindungsqualität beim Clinchen aufgezeigt. &nbsp; Sheet metal components are manufactured in various cutting and forming operations influencing the resulting properties of the parts. As these properties differ from the initial state of the semi-finished products, they have to be considered in the design of clinched joints. By connecting individual processes, this paper presents an approach for determining the properties of semi-finished parts in shear-cutting operations as well as their effects on the joint quality in clinching.

As there was no superior probability of survival, and there have been concerns on putative local and systemic toxicity of metal debris, the use of second-generation metal-on-metal articulations for primary THR remains moot.

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Abstract.Recently, there is rising demand of electronic systems with functional density for industrial and automotive applications. Those components, which are typically manufactured by overmoulding blanked metal inserts within an assembly injection process, are often exposed to rough operating conditions. Especially penetrating water can lead to a severe damage of electronic systems which are often crucial to safety. Leakage can be caused among other things by crack initiation within the polymer at sharp edges of the metal insert as a consequence of stress concentration. In order to reduce stress concentration the effect of metal inserts with rounded edges and the forming process to manufacture such inserts is investigated. Since typical sheet thicknesses for electronic components are 1 mm and less the dimensions of the rounded edges are on the scale of micro features. The microforming operation of rounded edges is provided by open coining. The influence of varying part dimensions is investigated using FE-simulation. Furthermore, ideal rectangular insert shapes are compared to parts with sheared edge geometry. In addition the effect of rounded edges on stress distribution of overmoulded parts is analysed by combining resulting geometries of the forming simulation with the numerical analysis of stress distribution within the polymer.