Trans-sulcus Angle Guide

A line is drawn down the deepest part of the trochlear sulcus (Whiteside line) with a marking pen or cautery. The post on the guide is inserted into the hole in the femur made for an intra-medullary alignment guide. The trans-sulcus angle guide is then rotated until the line on the guide lines up with the Whiteside line. A line is then drawn along the bottom of the guide.