US Patent 9186161 Surgical tools for arthroplasty

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.