An intramedullary fixation device includes an intramedullary implant having a longitudinal bore along a longitudinal axis, a two-component compression device and a two-component locking device, both devices preassembled in the longitudinal bore. The intramedullary implant includes an elongated slot and first and second apertures transversely crossing the longitudinal axis. The compression device is movable along the longitudinal axis and defines an end opening aligned with the elongated slot of the intramedullary implant. The locking device includes first and second openings aligned along the first and second apertures of the intramedullary implant.