The apparatus has a stabilization element configured as a helical spring (10) that is introduced into a cavity of a long bone, and comprising a fixation device at an end of the element. The helical spring has a normalized, uniformly configured head that is independent of a variable outer diameter (d) of the helical spring. An axially projecting pin (12) is provided at the head, formed of a winding (11) and is connected with the head. The outer diameter of the helical spring tapers or extends over length of a section. Independent claims are also included for the following: (1) a device for fixing a long bone fractures stabilizing apparatus on the long bone (2) a tool for screwing a long bone fractures stabilizing apparatus into or out of the long bone.