A trackable guidewire apparatus and method for use are described. Longitudinally spaced proximal and distal guidewire ends are separated by a guidewire body. A plurality of longitudinally spaced position sensors are configured to provide signals corresponding to a three-dimensional position of at least one position sensor in a coordinate system of an associated tracking system in response to an electromagnetic field/stimulus. At least one retention mechanism is provided for maintaining the medical device in a predetermined retention position longitudinally along the guidewire body. At least one stop structure is provided in a predetermined stop position longitudinally along the guidewire body.