The invention relates to a device (2), and to a system (1) comprising such a device, for fixing a spinal vertebra to a rod (3), comprising a pedicle screw and an anchor lug for fixing the screw to the rod. The device comprises a flexible strip for connection to the vertebra, a ring secured to the lug, and means secured to said ring, for adjustably locking the flexible strip in relation to the anchor lug.
