Abstract: A method for performing a surgical procedure related to a pelvis of a patient comprises adjusting a length between ends of a digitizer device to a distance between opposite landmarks of the pelvis of the patient. The ends of the digitizer device are applied against the opposite landmarks of the pelvis. An inertial sensor unit of the digitizer device is initialized to set an orientation of the digitizer device relative to a medio-lateral axis of the patient, the medio-lateral axis of the patient being part of a pelvic coordinate system. A tool is navigated within the pelvic coordinate system during a surgical procedure.

Abstract: A method for assisting in positioning the acetabular cup comprises orienting a cup positioning instrument with a cup thereon in an initial reference orientation relative to an acetabulum of a pelvis with the cup forming a joint with the acetabulum, the cup positioning instrument comprising an inertial sensor unit with pre-planned orientation data for a desired cup orientation based on at least one landmark of the pelvis, The cup positioning instrument is rotated to a desired abduction angle as guided by an interface of the cup positioning instrument, based on movements relative to at least one landmark. The cup positioning instrument is rotated to a desired anteversion angle as guided by the interface of the cup positioning instrument, based on movements relative to the at least one landmark. Upon reaching the desired cup orientation as indicated by the interface, the cup is impacted into the acetabulum.

Abstract: A method for assisting in positioning the acetabular cup comprises orienting a cup positioning instrument with a cup thereon in an initial reference orientation relative to an acetabulum of a pelvis with the cup forming a joint with the acetabulum, the cup positioning instrument comprising an inertial sensor unit with pre-planned orientation data for a desired cup orientation based on at least one landmark of the pelvis, The cup positioning instrument is rotated to a desired abduction angle as guided by an interface of the cup positioning instrument, based on movements relative to at least one landmark. The cup positioning instrument is rotated to a desired anteversion angle as guided by the interface of the cup positioning instrument, based on movements relative to the at least one landmark. Upon reaching the desired cup orientation as indicated by the interface, the cup is impacted into the acetabulum.

Abstract: A digitizer device comprises an elongated body and legs connected to the elongated body. At least one joint is between the legs and the elongated body such that free ends of the legs are displaceable relative to one another. An inertial sensor unit is connected to the elongated body, the inertial sensor unit having a preset orientation aligned with the elongated body. A table reference device comprises a body adapted to be fixed to an operating table. An inertial sensor unit is with a preset orientation related to the operating table.

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 device for digitizing a center of rotation of a hip joint implant component with respect to a bone element in computer-assisted surgery. The device comprises a detectable member trackable for position and orientation by a computer-assisted surgery system. A body is connected to the detectable member in a known geometry. The body has a coupling portion adapted to be coupled to the hip joint implant component in a predetermined configuration. The center of rotation of the hip joint implant component is calculable in the predetermined configuration as a function of the known geometry and of the position and orientation of the detectable member.

Abstract: A method of calibrating a circular portion of an object, such as to determine the center point thereof, is provided. The method comprising determining spatial coordinates of at least two points on a circumferential edge of the circular portion of the object, and calculating the center point of the circular portion using the spatial coordinates of the two points and a geometric parameter representative of the diameter of the circular portion. A calibration device and system are also provided for use with a computer tracking system in order to calibrate such an object having a circular portion.

Abstract: A hip resurfacing CAS system for guiding an operator in altering a femoral head in computer-assisted surgery for subsequent implanting of a femoral head implant, comprises a trackable reference on the femur. A registration tool is trackable. A bone-altering tool is associated with a resurfacing of the femoral head. A tracking apparatus tracks the tools. A resurfacing processing unit is connected to the tracking apparatus so as to receive tracking data for the tools. The resurfacing processing unit has a position/orientation calculator to calculate from the tracking data a position and orientation of the trackable reference to track the femoral frame of reference, and of the registration tool and the bone-altering tool. A model generator receives position and orientation data of the registration tool to produce a model of the femoral head and neck with respect to the femoral frame of reference.

Abstract: An interface apparatus (20) for tracking by a tracking system (40) of an object(s) in space for position and orientation and for interacting with the tracking system (40). The interface apparatus (20) comprises passive detectable devices (12,14,16,22) trackable for position by the tracking system (40). A mounting device (10,24) receives the passive detectable devices (12,14,16,22) in a known geometry, and is secured to the object(s) such that a position and orientation of the object(s) is calculable by the tracking system (40) as a function of a tracking of the known geometry of the passive detectable devices (12,14,16,22). One of the passive detectable devices (22) is displaceable with respect to the object(s). A displacement of the passive detectable device (22) with respect to the object(s) is detectable to initiate an interaction with the tracking system (40) while maintaining the tracking of the object(s).

Abstract: A computer-assisted surgery system for guiding an operator in altering a pelvis. A sensing apparatus is provided for tracking a reference tool and a bone altering tool. A position calculator calculates a position and orientation of a pelvic frame of reference as a function of the tracking of the reference tool, and for calculating a position and orientation of the bone altering tool with respect to the frame of reference. A source of posture data and a posture data correction calculator are provided and are operative to provide a display of information allowing an operator to take into consideration the posture data from the source of posture data when altering the pelvis. A display unit is connected to the position calculator and to the posture data correction calculator for displaying the display of information and the bone altering tool with respect to the pelvic frame of reference.

Abstract: A surgical bone reference assembly for communication with a CAS system, comprises a bone anchor fastenable to a bone element, an adjustable support and a trackable member that is located and tracked in three dimensional space by the CAS system. The support is removably fastenable to the bone anchor member and permits variable positioning relative to the bone anchor member. The support is intra-operatively detachable from and re-fastenable to the bone anchor member. A method of using a CT-free CAS system for determining a change in position of an un-tracked target limb is also provided. The method comprises engaging the trackable bone reference member to another bone element, locating and digitizing a landmark on the target limb, digitizing the landmark again following joint reduction, and determining at least one of a post-joint reduction limb length discrepancy and a target limb medio-lateral offset.

Abstract: A surgical bone reference assembly is communicable with an image guided surgical system such that position and movement of a bone element are monitorable. A bone anchor member comprises a trackable member and teeth engageable with the bone element. The trackable member comprises a detectable element adapted to be located and tracked in three dimensional space by the image guided surgical system, thereby defining position and movement of the trackable member. A protective guide member is used with the bone anchor member such that the bone anchor member is insertable through soft tissue covering the bone element without causing significant damage thereto. The bone anchor member is engageable with the bone element, such that the teeth are forced into engagement with the bone element and the bone anchor member is fastenable to the bone element in a fixed relation thereto.

Abstract: There is described a method for determining a mechanical axis of a femur using a computer aided surgery system having an output device for displaying said mechanical axis, the method comprising: providing a position sensing system having a tracking device capable of registering instantaneous position readings and attaching the tracking device to the femur; locating a center of a femoral head of the femur by moving a proximal end of the femur to a first static position, acquiring a fixed reading of the first static position, repeating the moving and the acquiring for a plurality of static positions; and locating the centre by determining a central point of a pattern formed by the plurality of static positions; digitizing an entrance point of the mechanical axis at a substantially central position of the proximal end of the femur; and joining a line between the entrance point and the center of rotation to form the mechanical axis.

Abstract: A surgical bone reference assembly adapted for communication with an image guided surgical system. A bone anchor member is engageable to a bone element of a patient such that substantially no relative movement therebetween is possible. A trackable member comprises a detectable element adapted to be located and tracked in three dimensional space by the image guided surgical system, thereby defining position and movement of the trackable member. An adjustable articulated support member links the trackable member and the bone anchor member, and permits variable positioning of the trackable member relative to the bone anchor member, while being lockable to fix the trackable member in position relative to the bone anchor member.

Abstract: A surgical bone reference assembly is communicable with an image guided surgical system such that position and movement of a bone element are monitorable. A bone anchor member comprises a trackable member and teeth engageable with the bone element. The trackable member comprises a detectable element adapted to be located and tracked in three dimensional space by the image guided surgical system, thereby defining position and movement of the trackable member. A protective guide member is used with the bone anchor member such that the bone anchor member is insertable through soft tissue covering the bone element without causing significant damage thereto. The bone anchor member is engageable with the bone element, such that the teeth are forced into engagement with the bone element and the bone anchor member is fastenable to the bone element in a fixed relation thereto.

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 resealable transfer assembly for a container such as a bottle or vial featuring a membrane for selectively opening or sealing a fluid path between the bottle and a medical delivery device introduced into the assembly. The assembly includes a body disposed on the bottle, and a luer connector hub which may be separately provided with the body or formed integrally therewith. A free plug rests in a cavity defined within the luer connector hub. The free plug includes an orifice dimensioned to accept a luer tip associated with the medical delivery device. A membrane, preferably formed from an elastomeric material, is secured across both the opposed end of the luer connector hub and the open top of the bottle, and may be retained between the top surface of the bottle and the body. The membrane preferably includes a central area sealing the opposed end of the luer connector hub from the open top of the bottle, with one or more fluid openings defined on a portion of the membrane outside of the central area.

Abstract: A mechanical pipe expander having a pyramidal, polyhedronal cross-section, segments resting against the pyramidal surfaces which are displaceable in axial direction relative to the polyhedron, and grooves formed in the longitudinal centers of the edges of the polyhedron so that the side surfaces of the grooves represent guides for the correspondingly shaped segments. The segments are formed as dove tails on the leading end thereof over a length of about 5-30% of their total length and each of the side surfaces of the dove tail recesses slide on a side surface of two adjacent grooves formed in the polyhedron. The length of the grooves is limited to the path of displacement of the polyhedron with respect to the segments, and the ends of the segments facing away from the leading end are held by radially acting springs against the surfaces of the polyhedron.

Abstract: The invention concerns a method and an apparatus for the automatic control of a guided vehicle (2) and proposes a new safety concept which, if breakdowns and/or emergencies arise, prevents the vehicle from being stopped in tunnels, on bridges or on pathless terrain. The invention lies in that between preselected stopping regions (11, 12, 13) provided with system for evaluation of passengers and for intervention by rescue services, the vehicle is always operated at such a high speed that even if the driving force fails, travel can still continue from every point of the line on account of its instantaneous momentum at least as far as a preselected subsequent stopping region in the direction of travel, and if a breakdown and/or emergency situation arises the vehicle (2) is brought to a standstill by initiation of automatic train stop or target automatic train stop in this preselected stopping region (FIG. 1).

Abstract: A sealing arrangement around an end of a pipe received in a testhead of a hydraulic pipe testing apparatus, which sealing arrangement consists of an elastic sealing ring and an adjacent, rigid support ring of varying diameters. Both rings are mounted in radial recesses in the testhead and encircle the pipe upon its entry into the testhead. The recess for the elastic sealing ring consists of a flat ring located between the sealing ring and the rigid support ring. For a sealing condition, the support ring is contracted to abut the pipe and the sealing ring is caused to be deformed whereby it flows radially outwardly from its recess against the pipe and axially along the pipe towards and away from the pipe's end. In the axial direction away from the end of the pipe, the sealing ring flows around the flat ring to abut the rigid support ring.