Abstract: A computer assisted surgery system for conducting orthopedic surgery on a knee joint includes a condyle digitizer having a posterior condyle abutment surface defining a first plane and a distal condyle abutment surface defining a second plane perpendicular to the first plane, and a trackable member which is locatable and trackable in three dimensional space by the computer assisted surgery system to define at least orientation of the condyle digitizer in real time. A computer determines a most remote reference point of the femur of the knee joint lying within at least one of the first and second planes when the condyle digitizer is abutted against condyles of the femur such that the posterior condyle abutment surface abuts a posterior side of the condyles and the distal condyle abutment surface abuts a distal side of the condyles.

Abstract: A method of determining a reference point on condyles of a femur uses a computer assisted surgery system having a digitizer with perpendicular first and second planar surfaces, the digitizer being locatable and trackable in three dimensional space by the computer assisted surgery system. A digitized plane is created using the digitizer, the digitized plane being a posterior plane and/or a distal plane of the condyles. The posterior plane and the distal plane are respectively defined by the first and second planar surfaces of the digitizer. A location of the reference point in the digitized plane is then determined using the computer assisted surgical system. The reference point is a most remote point of the femur within the digitized plane.

Abstract: A device (10,10?,20,20?) for digitizing a center of rotation of a hip joint implant component (A,F) with respect to a bone element in computer-assisted surgery. The device (10,10?,20,20?) comprises a detectable member (12,22) trackable for position and orientation by a computer-assisted surgery system (30). A body (11,21) is connected to the detectable member (12,22) in a known geometry. The body (11,21) has a coupling portion (14,14?,24,25) adapted to be coupled to the hip joint implant component (A,F) in a predetermined configuration. The center of rotation of the hip joint implant component (A,F) is calculable in the predetermined configuration as a function of the known geometry and of the position and orientation of the detectable member (12,22).

Abstract: A system for tracking a femoral frame of reference in computer-assisted surgery comprises a sensor unit. The sensor unit is adapted to be secured to the femur. The sensor unit comprises accelerometer and gyroscope sensors that produce orientation data. A processing unit receives gyroscope and accelerometer data. The processing unit comprises a gyroscope-data calculator to provide calculated acceleration data resulting from movements of the femur, an accelerometer-data calculator to calculate measured acceleration data resulting from movements of the femur, and an acceleration comparator to relate an orientation of the sensor unit to the femur to define a femoral frame of reference. The femoral frame of reference is defined from the comparison between the calculated and the measured acceleration data. A sensor orientation interface provides orientation data for the femur from a tracking of the femoral frame of reference. A method for tracking a femoral frame of reference is also provided.

Abstract: A CAS system and method comprises a first reference in fixed relation with the pelvis and a registration tool. A sensor apparatus tracks the first reference and tool. A controller unit receives tracking data for the first reference and tool. A calculator tracks the pelvic frame of reference, and the tool to produce a femoral frame of reference at two sequential operative steps. A reference orientation adjustor receives tracking data for the pelvic frame of reference to orient the femoral frame of reference in a reference orientation with respect to the pelvic frame of reference, and to produce a reference adjustment value as a function of the reference orientation. A surgical parameter calculator receives tracking data from the tool to calculate surgical parameters as a function of the reference adjustment value.

Abstract: There is described a device for use with a position sensing system for tracking a bone in a reference coordinate system, the device comprising a fabric removably and non-invasively attachable to a bone and having a plurality of reference markers distributed thereon, the reference markers being one of passive and active devices recognized by the position sensing system and positioned and oriented in the reference coordinate system with respect to a fixed reference.

Abstract: A surgical reference device for use with a computer-assisted surgery system comprises an engaging member adapted to engage directly on soft tissue of a body part such that substantially no relative movement is possible between the engaging member and a bone element of the body part. A trackable member is attached to the engaging member and comprises a detectable element for being located and tracked in three-dimensional space by the computer-assisted surgery system to measure a position and an orientation of the trackable member in time, whereby the bone element is tracked as a function of the position and orientation of the trackable member. A method for tracking a position and an orientation of a bone element using a computer-assisted surgery system is also provided.

Abstract: A positioning device assembly for positioning a tool guide block for use in an orthopedic surgery on a bone element includes a positioning device having a block body with a reference surface adapted to abut the bone element, and first and second adjustment mechanisms that are independently operable. The first adjustment mechanism permits rotation of a tool guide block about a medial-lateral extending axis such as to provide flexion-extension angle adjustment and the second adjustment mechanism permits rotation of a tool guide block about an anterior-posterior extending axis such as to provide varus-valgus angle adjustment. The second adjustment mechanism includes both a coarse and a fine adjustment mechanism integral therewith. A tool guide block assembly mounted to the positioning device, the tool guide block assembly including a platform portion which is engaged to the block body of the positioning device and the tool guide block which is releasably engaged with the platform.

Abstract: A computer-assisted surgery system for planning/guiding alterations to a bone in surgery, comprises a trackable member adapted to be secured to the bone. The trackable member has a first inertial sensor unit producing orientation-based data for at least two degrees of freedom in orientation of the trackable member A positioning block is adapted to be secured to the bone, with at least an orientation of the positioning block being adjustable once the positioning block is secured to the bone to reach a selected orientation at which the positioning block is used to guide tools in altering the bone. The positioning block has a second inertial sensor unit producing orientation-based data for at least two degrees of freedom in orientation of the positioning block. A processing system providing an orientation reference associating the bone to the trackable member comprises a signal interpreter for determining an orientation of the trackable member and of the positioning block from the orientation-based data.

Abstract: A tracking system is provided for tracking an objects. A first and a second trackable member each have an inertial sensor unit producing at least orientation-based data. A processing unit receives the orientation-based data from the trackable members. The processing unit has an orientation calculator calculating an orientation of the second trackable member with respect to the first trackable member from the orientation-based data of both said trackable members, whereby the processing unit calculates an orientation of the objects. A method is also provided.

Abstract: A system for calculating a position and orientation of an acetabular cup in computer-assisted surgery comprises a first trackable reference secured to a pelvis, with a frame of reference being associated with the first trackable reference. A device is positionable between a femoral neck and the acetabulum of the pelvis in a known relation, the device having a second trackable reference. Sensors track the trackable references for position and orientation. A position/orientation calculator calculates a position and orientation of the frame of reference and of the device and for determining an orientation of the neck axis with respect to the frame of reference from the known relation at a desired position of the femur. An implant position/orientation calculator provides cup implanting information with respect to the orientation of said neck axis as a function of the tracking for position and orientation of at least the first trackable reference.

Abstract: There is described a method and a system for generating a non-imaged plane view of an anatomical part for assisting a surgery. A model of the anatomical part is provided, comprising features and dimension parameters. A first plane view of the anatomical part is obtained. Features are identified in the first plane view. The dimension parameters are measured from the features identified. The model is displayed in the non-imaged plane view such that the model is dimensioned with the measured dimension parameters. A position and orientation of a surgical object is then tracked relative to the anatomical part while a user navigates said surgical object in space and a representation of the surgical object to be overlaid in register on at least one the first plane view and/or the non-imaged view is generated.

Abstract: There is described a system and a method for assisting a user manipulating an object during a surgery, the method comprising: tracking the object in a sterile field in which surgery is being performed at a location using a tracking device which generates tracking data; processing the tracking data using a processing device located outside the sterile field to generate position and orientation information related to the object; and sending the position and orientation information related to the object to a displaying device positioned in the sterile field adjacent to the location at which the surgery is being performed, for display to the user.

Abstract: A surface digitizing tool has a film of micro-sensor elements, with each micro-sensor element related in a network affected by a shape of the film. The film is flexible to conform to a shape of a selected surface of an object. A processing unit receives signals from the micro-sensor elements of the network. The processing unit has a model generator producing a model of the selected surface of the object from the signals of the network of resistive elements. A positioning frame aligns a position and orientation of a drilling tool with respect to a bone element.

Abstract: There is described a device for use with a position sensing system for tracking a bone in a reference coordinate system, the device comprising a fabric removably and non-invasively attachable to a bone and having a plurality of reference markers distributed thereon, the reference markers being one of passive and active devices recognized by the position sensing system and positioned and oriented in the reference coordinate system with respect to a fixed reference.

Abstract: There is described a device for use with a position sensing system to register position and orientation in a reference-coordinate system, the device comprising a set of at least three base units removably and non-invasively attachable to a skin surface covering a bone, each of the base units having a reference marker attached thereto, the reference markers being one of passive and active devices recognized by the position sensing system and positioned and oriented in the reference coordinate system with respect to a fixed reference, the base units adapted to measure a distance between the skin surface and the bone in conjunction with an ultrasound component.

Abstract: A drill guide assembly (10) for a drilling tool (50) having a chuck engaging a bit portion (54) comprising a tip (62) and a length extending from the chuck, the drill guide assembly comprising a first member (14), a second member (12) and a trackable member (16). The first member (14) is adapted to abut a workpiece surface and defines a central aperture (19) therethrough adapted to receive the bit portion. The second member (12) is adapted to be axially displaced with respect to the first member and is axially biased therefrom, and defines a central aperture (11) therethrough adapted to receive the bit portion. The trackable member (16), fastened to the second member, comprises a detectable element (35) adapted to be located and tracked in three dimensional space, thereby defining the position and movement of the second member and therefore that of the drilling tool bit portion.

Abstract: A method of determining a reference point on condyles of a femur uses a computer assisted surgery system having a digitizer with perpendicular first and second planar surfaces, the digitizer being locatable and trackable in three dimensional space by the computer assisted surgery system. A digitized plane is created using the digitizer, the digitized plane being a posterior plane and/or a distal plane of the condyles. The posterior plane and the distal plane are respectively defined by the first and second planar surfaces of the digitizer. A location of the reference point in the digitized plane is then determined using the computer assisted surgical system. The reference point is a most remote point of the femur within the digitized plane.

Abstract: A registration pointer for registering points of surfaces of bodily elements in computer-assisted surgery, comprising a handle for being manipulated by a pointer operator. A stem is connected to the handle and has a first and a second tip configurations each having a respective use relating to a registration of points on specified bodily elements. A detectable device is secured to the stem, and is adapted to be tracked in space for position and orientation by a sensing apparatus. A position of the tip configurations with respect to the detectable device is determinable such that a position of the tip configurations is calculable as a function of the position and orientation of the detectable device. The tip configurations are chosen to register points on given bodily elements as a function of the respective use, by recording a position of points of contact between the tip configurations and the given bodily element.

Abstract: A tracker device of the type is associated with a surgical instrument and being trackable in space by a CAS system such that a position of the surgical instrument is calculable. A support is adapted to be connected to the surgical instrument. Optical elements are mounted to the support in a first pattern so as to be detectable by the CAS system along a first range of visibility. Other optical elements are mounted to the support in a second pattern so as to be detectable by the CAS system along a second range of visibility, with the first range of visibility and the second range of visibility having at most a common portion, whereby a position of the surgical instrument is tracked within the first and the second range of visibility as a function of the detection of any one of the patterns of the optical elements.