Abstract: Apparatus for the dynamic stabilization of bone fragments, in particular spinal vertebrae (V), with at least one longitudinal support (11) that can be fixed to the vertebrae (V). The at least one longitudinal support (11) is so constructed that by application of a prespecified bending force it can be plastically deformed from a first stable shape state into a second, alternative stable shape state, but while in the first as well as in the second state remains flexible within predetermined limits. Preferably the longitudinal support (11) comprises a metallic core (12) surrounded by a plastic casing (13).