Abstract: There is provided a method and system for determining a distal cut thickness and posterior cut thickness for a femur in a knee replacement operation, the method comprising: performing a tibial cut on a tibia; performing soft tissue balancing based on a desired limb alignment; measuring an extension gap between the femur and said tibial cut while in extension; measuring a flexion gap between the femur and the tibial cut while in flexion; calculating a distal cut thickness and a posterior cut thickness for the femur using the extension gap and the flexion gap and taking into account a distal thickness and posterior thickness of a femoral implant; and performing said femoral cut according to the distal cut thickness and posterior cut thickness.

Abstract: A positioning block for use in knee surgery includes a rotational mounting removably engageable to the bone element by a multi-axial fastener such that the mounting element is selectively rotatable relative to the bone element about at least two substantially perpendicular axes of rotation. A guide body portion is engaged with the rotational mounting element such that it is translatable relative thereto along while being rotationally fixed relative to the mounting element. The guide body portion is moveable relative to the bone element in at least three degrees of freedom, the three degrees of freedom including at least two rotational degrees of freedom and at least one translational degree of freedom. A trackable member on the guide body portion is identified and tracked by a computer assisted surgery system.

Abstract: A positioning block (10) for use in total knee replacement surgery, permitting five degrees-of-freedom movement relative to a bone element (39) to which it is fixed. The positioning block (10) comprises a rotational mounting element (14) that is removably engaged to the bone element such that the mounting element (14) is selectively rotatable relative to the bone element, about three substantially perpendicular axes of rotation. A guide body portion (12) is engaged with the mounting element (14) such that it is translatable relative thereto along a proximal-distal axis (43) and an anterior-posterior axis (47), while being rotationally fixed relative to the mounting element (14) such that the guide body portion (12) and the mounting element (14) rotate together relative to the bone element (39).

Abstract: A positioning block (10) for use in total knee replacement surgery, permitting five degrees-of-freedom movement relative to a bone element (39) to which it is fixed. The positioning block (10) comprises a rotational mounting element (14) that is removably engaged to the bone element such that the mounting element (14) is selectively rotatable relative to the bone element, about three substantially perpendicular axes of rotation. A guide body portion (12) is engaged with the mounting element (14) such that it is translatable relative thereto along a proximal-distal axis (43) and an anterior-posterior axis (47), while being rotationally fixed relative to the mounting element (14) such that the guide body portion (12) and the mounting element (14) rotate together relative to the bone element (39).

Abstract: A positioning block for use in knee surgery includes a rotational mounting removably engageable to the bone element by a multi-axial fastener such that the mounting element is selectively rotatable relative to the bone element about at least two substantially perpendicular axes of rotation. A guide body portion is engaged with the rotational mounting element such that it is translatable relative thereto along while being rotationally fixed relative to the mounting element. The guide body portion is moveable relative to the bone element in at least three degrees of freedom, the three degrees of freedom including at least two rotational degrees of freedom and at least one translational degree of freedom. A trackable member on the guide body portion is identified and tracked by a computer assisted surgery system.

Abstract: A positioning block (10) for use in total knee replacement surgery, permitting five degrees-of-freedom movement relative to a bone element (39) to which it is fixed. The positioning block (10) comprises a rotational mounting element (14) that is removably engaged to the bone element such that the mounting element (14) is selectively rotatable relative to the bone element, about three substantially perpendicular axes of rotation. A guide body portion (12) is engaged with the mounting element (14) such that it is translatable relative thereto along a proximal-distal axis (43) and an anterior-posterior axis (47), while being rotationally fixed relative to the mounting element (14) such that the guide body portion (12) and the mounting element (14) rotate together relative to the bone element (39).

Abstract: A positioning block (10) for use in total knee replacement surgery, permitting five degrees-of-freedom movement relative to a bone element (39) to which it is fixed. The positioning block (10) comprises a rotational mounting element (14) that is removably engaged to the bone element such that the mounting element (14) is selectively rotatable relative to the bone element, about three substantially perpendicular axes of rotation. A guide body portion (12) is engaged with the mounting element (14) such that it is translatable relative thereto along a proximal-distal axis (43) and an anterior-posterior axis (47), while being rotationally fixed relative to the mounting element (14) such that the guide body portion (12) and the mounting element (14) rotate together relative to the bone element (39).

Abstract: A positioning block (10) for use in total knee replacement surgery, permitting five degrees-of-freedom movement relative to a bone element (39) to which it is fixed. The positioning block (10) comprises a rotational mounting element (14) that is removably engaged to the bone element such that the mounting element (14) is selectively rotatable relative to the bone element, about three substantially perpendicular axes of rotation. A guide body portion (12) is engaged with the mounting element (14) such that it is translatable relative thereto along a proximal-distal axis (43) and an anterior-posterior axis (47), while being rotationally fixed relative to the mounting element (14) such that the guide body portion (12) and the mounting element (14) rotate together relative to the bone element (39).

Abstract: The invention relates to a bipolar plate for a fuel cell, the plate being made up of two half-plates assembled one against the other via their inside faces, each half-plate including in its inside face at least a first groove and a second groove that are spaced apart from each other. The bottoms of said grooves each presenting a plurality of orifices distributed along each groove and opening out into the outside face of the half-plate. The outside face of each half-plate includes a plurality of distribution channels, each distribution channel connecting a respective orifice of the first groove to a respective orifice of the second groove.

Abstract: A structure for a fuel cell comprising at least one cell formed by first and second electrodes separated by a an electrolyte, the cell being disposed between first and second interface elements for feeding the electrodes of the cell with reagent and for collecting the electric current it produced. Each interface element comprises a distributor element of insulating material including distribution channels at least in its face facing one of the electrodes for the purpose of diffusing a reagent, and at least one collector element of conductive material interposed between the electrode and the elements made of insulating material. The collector element presents perforations so as to enable the reagent to diffuse between the channels of the distributor element and the electrode facing it.

Abstract: The invention relates to a bipolar plate for a fuel cell, the plate being made up of two half-plates assembled one against the other via their inside faces, each half-plate including in its inside face at least a first groove and a second groove that are spaced apart from each other. The bottoms of said grooves each presenting a plurality of orifices distributed along each groove and opening out into the outside face of the half-plate. The outside face of each half-plate includes a plurality of distribution channels, each distribution channel connecting a respective orifice of the first groove to a respective orifice of the second groove.

Abstract: There is provided a method and system for determining a distal cut thickness and posterior cut thickness for a femur in a knee replacement operation, the method comprising: performing a tibial cut on a tibia; performing soft tissue balancing based on a desired limb alignment; measuring an extension gap between the femur and said tibial cut while in extension; measuring a flexion gap between the femur and the tibial cut while in flexion; calculating a distal cut thickness and a posterior cut thickness for the femur using the extension gap and the flexion gap and taking into account a distal thickness and posterior thickness of a femoral implant; and performing said femoral cut according to the distal cut thickness and posterior cut thickness.

Abstract: A positioning block (10) for use in total knee replacement surgery, permitting five degrees-of-freedom movement relative to a bone element (39) to which it is fixed. The positioning block (10) comprises a rotational mounting element (14) that is removably engaged to the bone element such that the mounting element (14) is selectively rotatable relative to the bone element, about three substantially perpendicular axes of rotation. A guide body portion (12) is engaged with the mounting element (14) such that it is translatable relative thereto along a proximal-distal axis (43) and an anterior-posterior axis (47), while being rotationally fixed relative to the mounting element (14) such that the guide body portion (12) and the mounting element (14) rotate together relative to the bone element (39).

Abstract: A structure for a fuel cell comprising at least one cell formed by first and second electrodes separated by a an electrolyte, the cell being disposed between first and second interface elements for feeding the electrodes of the cell with reagent and for collecting the electric current it produced. Each interface element comprises a distributor element of insulating material including distribution channels at least in its face facing one of the electrodes for the purpose of diffusing a reagent, and at least one collector element of conductive material interposed between the electrode and the elements made of insulating material. The collector element presents perforations so as to enable the reagent to diffuse between the channels of the distributor element and the electrode facing it.

Abstract: A positioning block for use in total knee replacement surgery, permitting five degrees-of-freedom movement relative to a bone element to which it is fixed. The positioning block comprises a rotational mounting element that is removably engaged to the bone element such that the mounting element is selectively rotatable relative to the bone element, about three substantially perpendicular axes of rotation. A guide body portion is engaged with the mounting element such that it is translatable relative thereto along a proximal-distal axis and an anterior-posterior axis, while being rotationally fixed relative to the mounting element such that the guide body portion and the mounting element rotate together relative to the bone element.

Abstract: The tank for storing gas at high pressure, such as a tank for a vehicle running on gas, comprises a confinement volume accessible via coupling means and defined by a duct disposed in a spiral coil so that the substantially rectilinear main portions of the duct bear against one another. The forces exerted by the pressure of the gas on the main portions of a turn of the duct are then compensated by the forces exerted on the adjacent turns of the duct.

Abstract: The tank for storing gas at high pressure, such as a tank for a vehicle running on gas, comprises a confinement volume accessible via coupling means and defined by a duct disposed in a spiral coil so that the substantially rectilinear main portions of the duct bear against one another. The forces exerted by the pressure of the gas on the main portions of a turn of the duct are then compensated by the forces exerted on the adjacent turns of the duct.

Abstract: The retractable-gasket ball valve includes sealing means fixed on the valve body, and including, in particular, a gasket for providing sealing between the shutter member and the valve body when the shutter member is in a closed position, and further including a slide for causing said sealing means to move between a retracted position which is also a rest position in which the sealing means is spaced spart from the spherical shutter member, and a contact position in which the gasket is pressed against the shutter member. The valve includes a first resilient element of low stiffness which tends to separate the sealing means from the shutter member when the valve is brought to its open position, and a second resilient element of relatively greater stiffness which is put under tension by the slide a few degrees before the mechanical closure position of the valve when the gasket is in contact with the shutter member, and which exerts control pressure on said gasket in contact with the shutter member.

Abstract: A rotary actuator device having an annular piston rod, the device comprising at least one piston held provided with sealing means and co-operating with an annular piston rod mounted so as to be capable of moving in an annular chamber, together with means for selectively applying a fluid under pressure in said annular chamber, wherein the piston head co-operates with the piston rod via a hinge having one degree of freedom in rotation and one degree of freedom in translation, said hinge comprising a piece in the form of a knife whose edge co-operates with a V-groove in a female portion of triangular profile, the knife edge and the V-groove being parallel to the axis of rotation of the piston rod. This disposition enables the forces exerted on the sealing means to be brought back into balance, thereby increasing sealing even under high pressures.

Abstract: A ball valve comprising a valve body defining inlet and outlet sections, and a ball with a calibrated through-port. The valve further comprises a stem to rotate the ball between open and closed positions, a seal to insure a fluid tight closure of the valve when the ball is in the closed position, and a mechanism for retracting the seal. This seal retracting mechanism is selectively coupled to the stem, and the mechanism eliminates all contact, when the valve is in the open position, (i) between the ball and the seal, and (ii) between the stem and the seal retracting mechanism.