An orthopaedic surgical instrument includes a customized patient-specific surgical instrument having a body. The body has a bone-facing surface and an outer surface positioned opposite the bone-facing surface. The body includes a number of bone-contacting segments raised relative to the bone-facing surface. The bone-contacting segment include negative contours shaped to match corresponding positive contours of a patient's bone. The positive contours correspond to silhouette curves of a three-dimensional model of the patient's bone that correspond to contours of the patient's bone captured in images used to generate the model. The body further includes a number of surgical guides extending from the outer surface to the bone-contacting surface or the bone-facing surfaces. A method associated with the instrument is also disclosed.