US Patent 8177789 Distraction osteogenesis methods and devices

Methods and devices for distraction osteogenesis are disclosed employing an energy storage device and a controlled release of energy to provide a separating force. For example, bone expansion devices can include a first anchor element attachable to a first segment of bone, a second anchor element attachable to a second segment of bone, and an actuator for applying a separating force between the first and second anchor elements. The actuator can include a potential energy storage device and a controller for releasing energy from the energy storage device to provide the separating force.