An orthopaedic surgical instrument includes an all-polymer 4-in-1 cutting block having a number of polymer cutting guides. In some embodiments, the all-polymer cutting block is be embodied as a multi-piece cutting block, while in other embodiments the all-polymer cutting block is embodied as a single, monolith cutting block. Several methods for fabricating the different all-polymer 4-in-1 cutting blocks are also disclosed.