A collaboration was initiated many years ago by the mutual interest of Floris Lafeber from our department and Peter van Roermund from the department of orthopaedics UMC Utrecht, on the beneficial effects of unloading articular cartilage maintaining intermittent fluid pressure. This collaboration has over the years lead to 2 PhD theses (Valburg A and Marijnissen A), clear examples of translational research that lead to the clinical application of the concept in treatment of severe osteoarthritis with joint distraction. At present this work is continued by a 3rd PhD study (Intema F) intended to demonstrated structural joint repair due to joint distraction. Most importantly this collaboration has been extended to many aspects of cartilage regeneration using multiple models (brought in by both groups) and where biomechanical and biochemical aspects are combined in the attempt to regenerate cartilage in case of degenerative joint damage as in osteoarthritis.