A system for determining a position and an orientation of a bone of ananatomicalfeature includes a trackable reference device having a surgical pin at a firstpositionbeing attachable to the bone. A wearable attachment attached to the trackablereference device is configured to be mounted about the outer-skin surface oftheanatomical feature. A distance sensor mounted to the trackable referencedevice at asecond position is operable to determine a distance measurement of the secondposition of the trackable reference device from the bone. Reference markersare fixedlymounted to the trackable reference device. A position sensing device registerspositionand orientation readings of the reference markers in a reference coordinatesystem. Aprocessing unit determines the position and the orientation of the bone in thereferencecoordinate system using the position and orientation readings and the distancemeasurement.
