1. A method for registering a bone of a patient with a computer assisted orthopaedic surgery system, the method comprising: retrieving an image of the bone including indicia of the position of a magnet implanted in the bone, the image defining an image coordinate system; determining a position of a reference array coupled to the bone, the reference array defining a bone coordinate system; determining first data indicative of the position of the magnet in the bone coordinate system by determining a location of the centroid of the magnet using the following equation: 
 P B =RT[ 2] −1 *( RT[ 1]* P M ) wherein P B the location of the centroid of the magnet in the bone coordinate system, RT[ 1 ] is a first transformation matrix, RT[ 2 ] is a second transformation matrix, and P M is the location of the centroid of the magnet in the magnetic sensor array coordinate system; determining second data indicative of a correlation between the image coordinate system and the bone coordinate system based on the first data; and displaying an image of the bone in a position determined based on the second data.