An arrangement for determining position and fixation of an element relative to a part in or on a bone or a model of a bone. An expansion spacer extends through a sleeve. The spacer includes a first flange engages a first end of the sleeve and a second flange engages a second end of the sleeve when the spacer is expanded to vertically fix the spacer relative to the sleeve. An expansion screw extends through the spacer and includes an outer conical expansion surface configured to cooperate with an inner conical expansion surface on the spacer to radially expand the spacer causing the outer surface on the spacer to engage the inner surface of the sleeve, thereby determining the position of the sleeve relative to the part and fixing the sleeve.
