In various examples, an apparatus includes an instrument body (110) including a protrusion (130) configured to be sized according to an anatomy of a bone of a patient. A guide (150, 170) is configured to guide an aspect of a resection procedure of the bone, wherein the protrusion, when sized, is configured to abut the patients bone to maintain the instrument body in a first position with respect to the bone during at least part of the resection procedure.
