Updated project metadata. Bone fracture healing shows approximately 10-15% non-unions, although theoretically it has the potential of scarless regeneration. With regards to our aging society, a better understanding of the healing process is needed to allow for more sophisticated treatment options. Particular the early phase, which is a high complex and dynamic process in regards to nutrient and engery requirements. Here we investigate the proteomic (and metabolic) characteristics of the local microenvironment from successful (in young female Sprague-Dawley rats) and biologically compromised (in aged female rats with a minimum litter of three)bone reneration at day 3, 7 and 14 after osteotomy.