A system for conducting orthopedic surgery on a bone element comprising a computer assisted surgery system including a computer, a display device in communication with the computer, and a tracking system also in communication with the computer; wherein the system further comprises: at least two locating pins adapted to be fixed to the bone element; a drill guide having at least two substantially perpendicular abutment surfaces thereon which are adapted to be abutted against the bone element, at least two guide holes extending through the drill guide, located therein at positions disposed outside a predetermined region of the bone element when said abutting surfaces are in contact with their respective surfaces of the bone element, said guide holes being sized to accommodate the insertion of the locating pins therethrough, the predetermined region being a portion of the bone element that is to be resected; a bone reference having a first pair of holes therein which mate with said locating pins, said locating pins being fixable to the bone element via insertion through the guide holes of the drill guide, such as to engage the bone reference to said locating pins, the bone reference having a first trackable member thereon which is locatable and trackable in three dimensional space by the CAS system; and a cutting guide having a second pair of holes therein which mate with said locating pins, said locating pins being fixable to the bone element via insertion through the guide holes of the drill guide, such as to engage the cutting guide to said locating pins, the cutting guide including at least a distal cutting guide portion disposed at a determined resection distance relative to the bone element which is determined by the CAS system. at least two locating pins adapted to be fixed to the bone element; a drill guide having at least two substantially perpendicular abutment surfaces thereon which are adapted to be abutted against the bone element, at least two guide holes extending through the drill guide, located therein at positions disposed outside a predetermined region of the bone element when said abutting surfaces are in contact with their respective surfaces of the bone element, said guide holes being sized to accommodate the insertion of the locating pins therethrough, the predetermined region being a portion of the bone element that is to be resected; a bone reference having a first pair of holes therein which mate with said locating pins, said locating pins being fixable to the bone element via insertion through the guide holes of the drill guide, such as to engage the bone reference to said locating pins, the bone reference having a first trackable member thereon which is locatable and trackable in three dimensional space by the CAS system; and a cutting guide having a second pair of holes therein which mate with said locating pins, said locating pins being fixable to the bone element via insertion through the guide holes of the drill guide, such as to engage the cutting guide to said locating pins, the cutting guide including at least a distal cutting guide portion disposed at a determined resection distance relative to the bone element which is determined by the CAS system.