Feasibility of a Shape-Memory-Alloy-Actuator System for Modular Acetabular Cups

Research output: Contribution to journalResearch articleContributedpeer-review


  • Christian Rotsch - , Fraunhofer Institute for Machine Tools and Forming Technology, University Hospital Leipzig (Author)
  • Karoline Kemter-Esser - , Fraunhofer Institute for Machine Tools and Forming Technology (Author)
  • Johanna Dohndorf - , Chair of Biomedical Engineering, Fraunhofer Institute for Machine Tools and Forming Technology (Author)
  • Marcel Knothe - , IMA Materialforschung und Anwendungstechnik GmbH Dresden (Author)
  • Welf-Guntram Drossel - , Fraunhofer Institute for Machine Tools and Forming Technology, Chemnitz University of Technology (Author)
  • Christoph-Eckhardt Heyde - , University Hospital Leipzig (Author)


Hip implants have a modular structure which enables patient-specific adaptation but also revision of worn or damaged friction partners without compromising the implant-bone connection. To reduce complications during the extraction of ceramic inlays, this work presents a new approach of a shape-memory-alloy-actuator which enables the loosening of ceramic inlays from acetabular hip cups without ceramic chipping or damaging the metal cup. This technical in vitro study exam-ines two principles of heating currents and hot water for thermal activation of the shape-memory-alloy-actuator to generate a force between the metal cup and the ceramic inlay. Mechanical tests concerning push-in and push-out forces, deformation of the acetabular cup according to international test standards, and force generated by the actuator were generated to prove the feasibility of this new approach to ceramic inlay revision. The required disassembly force for a modular acetabular device achieved an average value of 602 N after static and 713 N after cyclic loading. The actuator can provide a push-out force up to 1951 N. In addition, it is shown that the necessary modifications to the implant modules for the implementation of the shape-memory-actuator-system do not result in any change in the mechanical properties compared to conventional systems.


Original languageEnglish
Article number75
Issue number1
Publication statusPublished - 12 Jan 2024

External IDs

ORCID /0009-0008-0416-6442/work/150881727
Scopus 85183099109
PubMed 38247952



  • shape memory alloy, Nitinol, NiTi, SMA, implant, hip implant, acetabular cup, extraction, implant revision