Abstract: Tools for resecting tibia and femur include anchoring devices, a three-way alignment guide attachable to the anchoring devices, two embodiments of a resection guide attachable to the alignment guide and equipped with couplings for trackers, a plane probe for examining the resected plane, and apparatus for EM alignment of the resection guide in the event of a computer failure. The methods of the invention include operating a computer aided navigation apparatus in the conventional manner including attaching one or more trackers to the bone to be resected; choosing a location for the anchoring device with or without guidance from the computer and installing the anchoring device; attaching the three-way alignment guide to the anchoring device; attaching a resection guide to the alignment guide; attaching one or two trackers to the resection guide; locating the resection guide with the aid of the alignment guide and the computer; fixing the resection guide to the bone with pins.

Abstract: Tools for resecting tibia and femur include anchoring devices, a three-way alignment guide attachable to the anchoring devices, two embodiments of a resection guide attachable to the alignment guide and equipped with couplings for trackers, a plane probe for examining the resected plane, and apparatus for EM alignment of the resection guide in the event of a computer failure. The methods of the invention include operating a computer aided navigation apparatus in the conventional manner including attaching one or more trackers to the bone to be resected; choosing a location for the anchoring device with or without guidance from the computer and installing the anchoring device; attaching the three-way alignment guide to the anchoring device; attaching a resection guide to the alignment guide; attaching one or two trackers to the resection guide; locating the resection guide with the aid of the alignment guide and the computer; fixing the resection guide to the bone with pins.

Abstract: Tools for resecting tibia and femur include anchoring devices, a three-way alignment guide attachable to the anchoring devices, two embodiments of a resection guide attachable to the alignment guide and equipped with couplings for trackers, a plane probe for examining the resected plane, and apparatus for EM alignment of the resection guide in the event of a computer failure. The methods of the invention include operating a computer aided navigation apparatus in the conventional manner including attaching one or more trackers to the bone to be resected; choosing a location for the anchoring device with or without guidance from the computer and installing the anchoring device; attaching the three-way alignment guide to the anchoring device; attaching a resection guide to the alignment guide; attaching one or two trackers to the resection guide; locating the resection guide with the aid of the alignment guide and the computer; fixing the resection guide to the bone with pins.

Abstract: Tools for resecting tibia and femur include anchoring devices, a three-way alignment guide attachable to the anchoring devices, two embodiments of a resection guide attachable to the alignment guide and equipped with couplings for trackers, a plane probe for examining the resected plane, and apparatus for EM alignment of the resection guide in the event of a computer failure. The methods of the invention include operating a computer aided navigation apparatus in the conventional manner including attaching one or more trackers to the bone to be resected; choosing a location for the anchoring device with or without guidance from the computer and installing the anchoring device; attaching the three-way alignment guide to the anchoring device; attaching a resection guide to the alignment guide; attaching one or two trackers to the resection guide; locating the resection guide with the aid of the alignment guide and the computer; fixing the resection guide to the bone with pins.

Abstract: A surgery system comprising at least one smart instrument, a computer system, and a sensor system. The sensor system is adapted to wirelessly sense the position of the at least one smart instrument and to transmit position information to the computer system.

Abstract: A calibrating device for detecting the position, firstly, of the axis of the shank (axis of action) and, secondly, of the front end (point of action or line of action) of a surgical instrument relative to an reference position determination device 42 mounted on the rear part of the instrument, has: two clamping-device carriers, each with a clamping device, in a clamping state the clamping devices bringing the shank of the instrument into a clearly defined clamped position; a supporting plate 12 on which the front end of the instrument rests in the clamped state; and a reference position determination device 42, the axis of action being essentially perpendicular to the supporting plate 12 in the clamped position, and the supporting plate and the reference position determination device 42 being connected firmly to one another.