A surgical kit includes a patient-specific alignment guide having a three-dimensional engagement surface custom-made by computer imaging to conform to a corresponding portion of a patients tibial bone. The patient-specific alignment guide defines an elongated planar slot for guiding a blade. The planar slot is oriented at a selected angle and at a selected position relative to an anatomic axis of the patient when the engagement surface engages the corresponding portion of the tibial bone. The selected angle and selected position are determined during a pre-operative planning stage.
