An orthopaedic surgical instrument system including a reamer assembly is disclosed. The reamer assembly includes a reamer head having a plurality of cutting teeth and a mounting bracket configured to be coupled to a femoral broach, which is sized to be positioned in a proximal opening of a femoral canal of a patient's femur. When the mounting bracket is coupled to the femoral broach, the reamer head is offset medially from the lateral edge of the femoral broach to resect a medial calcar of the patient femur.