A spinal interbody device (20) is provided having a cage (114) and an anchor (150). The cage (114) includes a center portion (136) with at least one surface (147). A first arm (138) and a second arm (138) extend from the center portion (136) with the first arm (138) having a pair of first projections (146) and the second arm (138) having a pair of second projections (148). The pair of first projections (146) and the pair of second projections (148) are disposed on opposing sides of an open side (144). The anchor (150) includes a blade (154) that is movable between a first position and a second position. The blade (154) is disposed to engage the first surface (147) and deflect as the anchor (150) is moved from the first position to the second position. Wherein the blade (154) is at least partially disposed between one of the pair of first projections (146) and the center portion (136) when the anchor (150) is in the second position.
