Abstract: An intervertebral disc prosthesis (1) having at least one upper plateau (4, 4?) and at least one lower plateau (5, 5?), which are separated by two movable cores (6, 6?) whose lower face (62, 62?) and upper face (61, 61?) respectively match a concave surface (54, 54?) of the upper plateau (4, 4?) and a convex surface (44, 44?) of the lower plateau (5, 5?). An intervertebral prosthetic unit (10) is also described having an intervertebral disc prosthesis and a posterior articular prosthesis (11) provided with two adjacent and partially tangent articular blades (12, 13), which are each coupled to a vertebra (3, 3?) by coupling devices (14) and are connected by guide devices that allow them to move along a curve whose centre C3 is provided on the same side as the implantation of said coupling means.