An arthroscopic tibial sizer provided with a collapsible loop (for example, a nitinol loop) and a pin indicator located at about the center of the collapsible loop. The collapsible loop is formed of a flexible wire (for example, nitinol wire) and is designed to collapse so that it can be inserted through an arthroscopic portal and into the joint, and then to expand out to its original diameter once inside the joint space, for visual sizing. The collapsible loop may be provided in various diameters (i.e., 14, 17 or 20 mm, for example) to match various implant sizes. The pin indicator indicates the center of the loop and provides identification of the center of the tibial defect.
