Abstract: An axial intramedullary screw having a straight cylindrical outer surface for the operative treatment of long bones, the screw having two tips and a screw thread extending between the tips. At each of the tips there is a connection portion for screwdriver. The screw thread is used for cutting into the cortical bone of the medullary canal and due to the screwdriver connection at both ends it can be driven from either end through the cortical bone. This allows a method to be used in which the screw is threaded into one portion of a bone fragment and then after connecting a further bone fragment at the fracture site, screwed in a different direction into that further fragment. The screw also includes a transverse screw hole at one or both ends for the passage of an interlocking transverse screw therethrough.

Abstract: The invention involves a differential and/or conical screw of a variable increasing pitch which is used for the initial mechanical stimulation of a healthy bone, in order to induce a new internal strain and the consequential biological reaction of the bone. The biological reaction results in the formation of a new, young superficial bone, and the process takes between 4 and 8 weeks. The new bone is used as an autologous bone transplant. The transplantation of this new bone into other parts of the body, where such a procedure is indicated, is a new method referred to as adaptive periosteal cambiplasty. The process of the implantation of the screws into the bone is controlled with the use of a special moment key, which provides for the induction of a defined and desired stimulation force, and it also provides for the safety of the method.