ZusammenfassungDer Hexapod ist eine in der Robotertechnik vielfach untersuchte Konstruktion für die dreidimensionale Positionierung. Unter anderem wird er in Flugsimulatoren für die räumliche Lagesteuerung des Cockpits verwendet. Durch Anwendung des Hexapodprinzips im Fixateur externe lassen sich vorgegebene Bewegungen von Knochenfragmenten mit einer einfachen und stabilen Konstruktion realisieren. Die exakte Einstellung des Systems erfordert eine Software, welche für die klinische Anwendung entwickelt und optimiert wurde. Translationen, Achskorrekturen und Rotationen sind sowohl einzeln als auch in Kombination zur Korrektur komplexer Fehlstellungen möglich. Besondere Vorteile bietet das System bei Rotationen um die Knochenlängsachse sowie bei der Realisierung von Translationsbewegungen. Durch die mathematische Berücksichtigung der Drehpunkte ergibt sich eine Vereinfachung der Planung von Korrekturen. Es wird das Hexapod-System beschrieben und die klinische Anwendung anhand von Beispielfällen dargestellt.SummaryThe hexapod is a construction that has been subjected to a great deal of investigation in robotics for use in three-dimensional positioning. One use of it is for positioning of the cockpit in flight simulators. Application of the hexapod principle in the external fixator makes it possible to realize prescribed movements of bone fragments with a simple and stable design. The precise setting of the system requires software that has been developed and optimized for clinical use. Translations, axis corrections and rotations are possible individually and also in combinations for correction of complex deformities. The system has advantages, especially in the case of rotations around the longitudinal axis of the bone and in the realization of translation movements. Because the centres of rotation are taken into account by the mathematical calculations, the planning of corrections is simplified. The hexapod system is described, and its clinical application is presented with reference to case reports.
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