RISystem AG 2 articles published in JoVE Medicine An Intramedullary Locking Nail for Standardized Fixation of Femur Osteotomies to Analyze Normal and Defective Bone Healing in Mice Tina Histing1, Michael D. Menger2, Tim Pohlemann1, Romano Matthys3, Tobias Fritz1, Patric Garcia1, Moritz Klein1 1Department of Trauma, Hand and Reconstructive Surgery, Saarland University, 2Institute for Clinical & Experimental Surgery, Saarland University, 3RISystem AG This protocol describes an osteosynthesis technique using an intramedullary locking nail for standardized fixation of femur osteotomies, which can be used to analyze normal and defective bone healing in mice. Medicine Adjustable Stiffness, External Fixator for the Rat Femur Osteotomy and Segmental Bone Defect Models Vaida Glatt1, Romano Matthys2 1Institute of Health and Biomedical Innovation, Queensland University of Technology, 2RISystem AG One constraint of preclinical research in the field of bone repair is the lack of experimental control over the local mechanical environment within a healing bone lesion. We report the design and use of an external fixator for bone repair with the ability to change fixator stiffness in vivo.