A slide-type cervical plate includes an anti-backout device (2) preventing the vertical movements of the bone anchor screws (3) and which consists of first vertical-blocking elements (71) capable of deforming elastically in a first direction so that an anchor screw (3) can be introduced into the corresponding bore (4) and of second vertical-blocking elements (8) capable of deforming elastically in a second direction different than the first so that another anchor screw (3) can be fitted into another bore (4), the first and second blocking elements deforming elastically when a combined external load in a vertical direction and in rotation in the clockwise direction is applied to the anchor screws (3).