Device (1) spinal fixation for maintaining a spinal vertebra (25) on a cylindrical shaft (2), comprising a body (3) fixing on the rod, a flexible band (4) binding of said vertebra with the fixing body and means (5) for adjustable locking of the flexible band on the fastening body, wherein the body (3) for fixing cross section U-shaped passage of the rod between the wall (10) bottom of the U and means of adjustable locking, said means (5) adjustable locking formed by a connecting piece (18) connecting the facing ends of the two branches (6, 7) of the U, comprising each being said branches (6, 7) a recess (14) facing, located on the bottom side of the U, namely a first recess for the passage of the free ends and a second hollow, on the other hand, for the passage of the appropriate band to form a loop for attachment to the vertebra, characterized in that the CUER po is formed in one piece, and in that the connecting piece (18) is formed by a clamping screw provided on the one hand, a head (19) through which a first branch (6) of the U, comprising said head a frustoconical portion (21) arranged to compress the rod (2) as occurs screwing and thus compress the two ends of the flexible band against the wall, and on the other hand, one end (20) screwed on the opposite branch of the U.Dispositivo (1) de fijación vertebral para el mantenimiento de una vértebra raquídea (25) sobre un vástago cilíndrico (2), que comprende un cuerpo (3) de fijación sobre el vástago, una banda flexible (4) de unión de dicha vértebra con el cuerpo de fijación y unos medios (5) de bloqueo regulable de la banda flexible sobre el cuerpo de fijación, siendo el cuerpo (3) de fijación de sección transversal en forma de U, de paso del vástago entre la pared (10) de fondo de la U y los medios de bloqueo regulable, estando dichos medios (5) de bloqueo regulable formados por una pieza de unión (18) que une los extremos enfrentados de las dos ramas (6, 7) de la U, comprendiendo cada una de dichas ramas (6,
