Refixation Loosened Hips

Het onderzoek

Minimally invasive refixation of loosened hip prostheses

Project leaders


Andriy Andreykiv PhD (Biomechanical modelling) | 2008 - 2010

PhD students

  • Francois (D.F.) Malan MSc (Image processing and visualisation) | 2008 - 2012
  • Gert Kraaij MSc (Instrument design) | 2009 - 2013


  • Biomechanical modelling
  • Image processing
  • Instrument design

Start/End Date

January 1 2008 - November 16 2013

Grant giver


Academic partners

  • Medical Visualisation Group, Faculty of 3mE, TU Delft
  • Department of Precision and Microsystems Engineering, Faculty  TU Delft
  • Department of Biomechanical Engineering, TU Delft
  • Division of Image Processing, Department of Radiology, LUMC
  • Clinical Physics, Department of Radiology, LUMC 

Commercial partners

  • Biomet B.V. Dordrecht, The Netherlands
  • Medis Medical Imaging B.V. Leiden, The Netherlands
  • DEAM


Worldwide, 150.000 hip prostheses have to be revised annually because they have become loose inside the patient’s bone. These loosened prostheses have very limited functionality, and patients experience intense pain, which makes them socially dependent. Open revision surgery is highly demanding for the patient as well as for the surgeon. Therefore, revision is impossible in 50.000 elderly patients with a poor general health condition. 

The aim of this project is to develop a reliable and generally usable minimally invasive surgical procedure in which loosened hip prostheses are refixated as an alternative for demanding open revision surgery.

The project has three major technological aspects: image processing and visualisation, biomechanical finite element modelling, and instrument design. In all three of them, we have the expertise to make innovative developments. In combination with our clinical expertise in open revision surgery and in minimally invasive surgical techniques, we will be able to come to a highly innovative surgical technique that relies on an integrated pre-operative planning platform and revolutionary new surgical instruments. We will develop novel surgical instruments that are based on mechanisms found in biology. These instruments will be used to accurately create bone cavities at well-defined positions. In turn, these cavities will be filled with cement in order to create cement anchors that stabilise and refixate the prosthesis. The optimal size and position of these anchors will be determined by patient-specific finite element models that are based on an accurate three-dimensional representation of the surgical site an d a clear segmentation of the various materials and tissues extracted from CT’s. For this, we will develop algorithms that improve the image quality and segment the different tissues. We will integrate these image processing algorithms, visualisation techniques, and patient specific biomechanical models in a highly interactive pre-operative planning environment that will assist the surgeon.