Abstract: A tool for digitizing a mechanical axis of a tibia using a computer-assisted surgery system is described. The tool includes upper and lower mounting ends interconnected by an alignment rod extending therebetween. The upper mounting end is releasably fastenable to an upper reference point on a tibial plateau and the lower mounting end includes a self-centering malleoli engaging mechanism having opposed caliper arms displaceable in a common plane relative to each other for clamping engagement with the medial and lateral malleoli of the ankle. At least one trackable member is mounted to the alignment rod of the tool and is in communication with the computer assisted surgery system for providing at least orientation information of the alignment rod. The mechanical axis of the tibia is parallel to the alignment rod and extends between the upper and lower reference points when the tool is mounted on the tibia.

Abstract: Devices and methods are provided for surgical repair of dilated aortic root to restore aortic valve competence while preserving native leaflets. In one aspect of the invention an expandable annuloplasty ring is provided for external placement at the base of a dilated aortic root. The expandable ring is capable of elastically expanding between a first diastolic diameter and a larger second systolic diameter to provide a physiologically representative surgical repair of the aortic root. In a further aspect of the invention, is provided a holder assembly for aortic annuloplasty ring and suitable for other cardiac valve prosthesis. The holder assembly consists of a holder body pivotingly coupled to a handle member through a ball-and-socket arrangement.

Abstract: Devices and methods are provided for surgical repair of dilated aortic root to restore aortic valve competence while preserving native leaflets. In one aspect of the invention an expandable annuloplasty ring is provided for external placement at the base of a dilated aortic root. The expandable ring is capable of elastically expanding between a first diastolic diameter and a larger second systolic diameter to provide a physiologically representative surgical repair of the aortic root. In a further aspect of the invention, is provided a holder assembly for aortic annuloplasty ring and suitable for other cardiac valve prosthesis. The holder assembly consists of a holder body pivotingly coupled to a handle member through a ball-and-socket arrangement.

Abstract: A method tracks a tool with respect to a bone in computer-assisted surgery. A reference tracker with a MEMS unit is secured to the bone. The tracker outputs data relating to its orientation. A tool provided with a MEMS unit and secured to the bone is preset with an initial orientation. The tool outputs tracking data related to orientation of the tool once initialized. A trackable frame of reference relating the bone to the orientation of the tracker is created. The MEMS unit of the tool is initialized. A relation between the initial orientation of the tool and the orientation of the tracker at initialization of the MEMS unit of the tool is recorded. Orientational data of the tool relative to the frame of reference of the bone calculated using the relation is displayed. A computer-assisted surgery system for tracking a tool with respect to a bone after an initialization of a MEMS unit is also described.

Abstract: A tool for digitizing a mechanical axis of a tibia using a computer-assisted surgery system is described. The tool includes upper and lower mounting ends interconnected by an alignment rod extending therebetween. The upper mounting end is releasably fastenable to an upper reference point on a tibial plateau and the lower mounting end includes a self-centering malleoli engaging mechanism having opposed caliper arms displaceable in a common plane relative to each other for clamping engagement with the medial and lateral malleoli of the ankle. At least one trackable member is mounted to the alignment rod of the tool and is in communication with the computer assisted surgery system for providing at least orientation information of the alignment rod. The mechanical axis of the tibia is parallel to the alignment rod and extends between the upper and lower reference points when the tool is mounted on the tibia.