[Biphasic plate-Controlled instability in fracture healing]

The bony consolidation of fractures depends on various factors. Under optimal conditions fracture healing takes place within a few weeks. An essential requirement for fracture healing is the restoration of adequate biomechanical stability with an interfragmentary movement which is as ideal as possible. Distal femoral fractures can be particularly challenging especially in the presence of extensive soft tissue damage, multiple fragmented fractures and involvement of the joint. The currently applied surgical techniques of single lateral plate, double plate and intramedullary nail osteosynthesis as well as combination procedures have a relatively high complication rate. The principle of the biphasic plate is based on the transverse and longitudinal slots placed in the plate, which enables a "controlled instability". This results in a relatively high interfragmentary movement even at low loads (flexible phase) and a low movement at high loads (stiff phase). Therefore, the implant becomes more rigid at higher mechanical demands. In biomechanical tests the stress distribution of the implant, the number of cycles up to failure and the maximum load are superior compared to the locking compression plate distal femur (LCP-DF). Future studies will need to compare and evaluate the potential clinical and economic benefits in direct comparison to the currently established surgical techniques. Preclinical studies have so far demonstrated the safety and applicability of the biphasic plate and the innovative principle of controlled instability in fracture healing.