A carpometacarpal joint replacement system for replacing the trapezium bone in the hand is provided. The system includes a trapezial implant for the carpometacarpal joint resulting in replacement of the carpal trapezium bone with a prosthesis having the same anatomical configuration as the trapezium bone. The implant device comprises a plurality of concave surfaces, with the plurality of concave surfaces articulating with the carpal and metacarpal bones.