A bone fusion implant system including a first implant body having substantially flat top and bottom surfaces for engaging opposing vertebrae and a side wall extending between the top and bottom surfaces, the side wall including a concave recess and a second implant body having substantially flat top and bottom surfaces for engaging the opposing vertebrae and a side wall extending between the top and bottom surfaces thereof, the side wall of the second implant including an arcuate portion adapted to be received within the concave recess for enabling the first and second implant bodies to be positioned in nested side-by-side relation between the opposing vertebrae.