The system (1) has two plates (2, 3) fixed on two successive vertebrae. An articulation unit is intercalated between internal faces (21, 31) of the plates. Support plates (4, 5) cooperate with any one of the two plates and comprise fixing parts (40, 50) applied to an anterior face of a vertebral body of one of the vertebrae. The plate is associated with the vertebra. The support plates cooperate with the vertebra. The fixing parts are fixed on the anterior face by screws (6). Connection parts (41, 51) of the support plates comprise distal ends that allow solidarization to the plates.
