In a device for injecting bone cement, the discharge direction of the bone cement after insertion of the cannula should be controllable in a certain region. This is made possible through a radial exit aperture (5) which is provided on the front end of the cannula (3). Since the cannula is inserted with the aid of a guide wire (1), it has an orifice (4) on its front end, which orifice must be closed off by means of a ball (15) prior to the injection. A plunger serves to insert the ball (15). So that the situation of the radial aperture (5) is known at all times, even with inserted cannula, the handle (17) of the cannula has an asymmetrical shape.
