Intervertebral device having expandable endplates

An intervertebral implant device having an expandable endplate, the endplate comprising:

• a) a first base portion having an outer surface adapted for bearing against a natural endplate, an inner surface, first and second side surfaces extending between the outer and inner surfaces, a first cutout opening onto the outer surface and the first side surface and forming a first recessed surface, and
• b) a first plank slidingly receivable within the first cutout and adapted to translate across the first recessed surface,
• wherein the first plank has a first shaft portion having a first outer end portion, a first inner end portion and a first pair of flexible arms extending from the outer end portion.