Anchoring device polyaxial bone, comprising an anchoring element (1) having a shank (2) for anchoring in the bone and a head (3), a receiving part (5, 5 ) for receiving and accommodating the head the anchoring element of bone and for receiving a rod (100), the receiving part an upper element (8, 8 ) with an upper end (81) and a lower end (82), a central axis (C) extends through the upper end and the lower end, a receiving head portion (84) with a step (85) at the lower end (82) for the head and a channel (86) for receiving the rod at the end upper (81) a lower element (10, 10 ) having an upper end (101) and a lower end (102) and a step (103, 104) extending from the upper end to the lower end, being connectable lower element the upper element from the lower end (82) of the upper element wherein at least one fixing element (20, 200) at the lower end (82) of the upper element or near the same, characterized in that at least one locking element (20, 200) protrudes into the passageway (85) of the receiving head portion (84) of the upper element (8, 8 ) when the lower member is connected to the top member to secure the head (3) when it is inserted in the receiving head portion (84).Dispositivo de anclaje de hueso poliaxial, que incluye un elemento de anclaje (1) que tiene un vástago (2) para anclarlo en el hueso y una cabeza (3), una pieza receptora (5, 5) para recibir y alojar la cabeza del elemento de anclaje de hueso y para recibir una varilla (100), incluyendo la pieza receptora un elemento superior (8, 8) con un extremo superior (81) y un extremo inferior (82), un eje central (C) que se extiende a través del extremo superior y del extremo inferior, una parte receptora de cabeza (84) con un paso (85) en el extremo inferior (82) para introducir la cabeza y un canal (86) para recibir la varilla en el extremo superior (81) un elemento inferior (10, 10) que tiene un extremo superior (101) y un extremo inferior (102) y un paso (103, 104) que se extiende desde el extremo su
