A patellar 3-D guidance tool includes a template. The template includes at
least one contact surface for engaging a surface of the patella. The at
least one contact surface substantially conforms with the surface
associated with the patellar. At least one guide aperture directs
movement of a surgical instrument, wherein the shape and/or position of
the guide aperture is based, at least in part, on three or more anatomic
reference points associated with the patellar.