A method for repairing focal defects in tissue of a patient using an instrument having a cutting tip and a drive motor for rotating the cutting tip includes the steps of receiving a virtual three-dimensional model of a bone created from scan data of the bone wherein the bone has a focal defect, creating a three-dimensional shape of a target volume of material to be removed from the bone, removing the target volume of the material from the bone with the cutting tip, and placing an implant into the bone to repair the focal defect.
