Abstract: A vertebral replacement device (1) includes a female part (2), a male part (3) that is mounted inside the female part (2) and can be axially displaced relative to the female part (2), first and second locking elements (14, 15) mounted so as to be movable in translation on the female part (2) in order to occupy a first position in which they cooperate with respective opposing parts (31) of a peripheral surface (6) of the male part (3) to axially lock the female and male parts (2, 3) relative to one another, and a second position in which the female and male (2, 3) parts can be freely displaced axially relative to one another, and a rotating control element (20) extending radially through the male part (3) this control element (20) cooperating with the locking elements (14, 15) so that, when a rotational movement is communicated to it, it transforms this rotational movement into a translational movement of each of the locking elements (14, 15) so as to bring the locking elements (14, 15) into either of the firs