Abstract: Systems, devices, and methods are provided for measuring forces in the space of a knee during surgery. Such forces can be caused by tension in the ligaments of the knee. A femoral member is engaged with a distal femur. While the knee is flexed, partially extended, or fully extended, a force sensor and a gauge shim can be placed in the gap between the femoral member and the tibial plateau to measure the forces therebetween. The force sensor provides an accurate and quantifiable measurement of force, making knee replacement surgery and ligament tension balancing more accurate, standardized and repeatable. The force sensor comprises an elongate housing which comprises a thin force sensing distal portion and a proximal handle portion.

Abstract: A method for positioning a bone cutting guide on a tibia may begin with coupling a bone cut positioning apparatus with a tibia. The method may also include adjusting the positioning apparatus in a varus/valgus orientation to shine a light emitted by a light emitter approximately along a midline of an anterior surface of the tibia, swinging a pivoting arm about a pivot joint to direct the emitted light along a medial surface of the tibia, adjusting the positioning apparatus in an anterior/posterior orientation to shine the light approximately along a midline of the medial surface, contacting a stylus with a proximal end of the tibia to select a cutting depth for a bone cut to be made on the tibia, and attaching the bone cutting guide to the tibia in a position determined by the positioning apparatus.

Abstract: Devices, systems, and methods are provided for facilitating the aligning and balancing of the knee dicing total knee replacement surgery. A femoral assembly is engaged with a distal femur. The positions of medial and lateral portions of the femoral assembly relative to a stationary portion of the femoral assembly can be separately adjusted to adjust the alignment of the knee. A force sensor will be provided to sense the force's m the medial and lateral portions of the knee, and the medial and lateral portions of the femoral assemblies will be adjusted so that the sensed forces are balanced. The alignment of the knee is visually verified using a knee alignment verification member coupled to the femoral assembly. The knee alignment verification member may emit laser beams along the mechanical axes of the femur and tibia, or the knee alignment verification member may couple to alignment rods aligned along these axes.

Abstract: A method for positioning a bone cutting guide on a tibia may begin with coupling a bone cut positioning apparatus with a tibia. The method may also include adjusting the positioning apparatus in a varus/valgus orientation to shine a light emitted by a light emitter approximately along a midline of an anterior surface of the tibia, swinging a pivoting arm about a pivot joint to direct the emitted light along a medial surface of the tibia, adjusting the positioning apparatus in an anterior/posterior orientation to shine the light approximately along a midline of the medial surface, contacting a stylus with a proximal end of the tibia to select a cutting depth for a bone cut to be made on the tibia, and attaching the bone cutting guide to the tibia in a position determined by the positioning apparatus.

Abstract: Methods, systems and devices are provided for facilitating a surgical procedure on a knee, particularly, a revision total knee replacement procedure. Prior femoral and tibial prostheses are removed. A cut end of a distal femur is engaged with a femoral adjustment member, which will typically center itself about an intermedullary rod placed into the femur. The lateral and medial forces exerted by lateral and medial sides of the femoral adjustment member and the cut tibial plateau against each other are measured. The femoral adjustment member is adjusted to apply and or adjust tension to the lateral collateral ligament and/or the medial collateral ligament based an the measured forces, for example, such that the measured lateral force and the measured medial force are matched. Based on the position of the adjusted femoral member, guided clean-up cuts for placement of a new femoral prostheses are made on the cut end of the distal femur.

Abstract: A method for positioning a bone cut on a bone may involve: coupling a bone cut positioning apparatus with a body bone; adjusting the positioning apparatus in a varus/valgus orientation relative to the body bone; adjusting the positioning apparatus in an anterior/posterior orientation relative to the body bone; and adjusting the positioning apparatus up or down to select a bone resection level.

Abstract: A device for performing a surgical procedure on a knee includes an adjustable femoral portion, a tibial portion and at least one sensor coupled with the femoral and/or tibial portions to sense pressure exerted by the femoral and tibial portions against one another. The femoral portion is adapted for removably coupling with a distal end of a femur to adjust tension in soft tissue adjacent the knee and has at least one positioning feature adapted to move relative to the distal end of the femur as the femoral portion is adjusted, thus helping position a femoral prosthetic on the distal end of the femur. The sensor(s) may be adapted to sense pressure at medial and lateral sides of the knee, and relative pressures may be displayed as data on a visual display. Adjustments to the femoral member may be made to balance pressure at flexion and extension of the knee.

Abstract: A monolithic material including a first region having a first variability of strength and a second region joined to the first region, the second region having a second variability of strength, wherein the monolithic material has a variability of strength less than the first variability of strength of the first region and less than the second variability of strength of the second region.

Abstract: A surgical saw includes a shaft, a first saw blade mounted on the shaft, a second saw blade mounted on the shaft parallel to the first saw blade, the first saw blade having a first tooth having two distal tips, and the second saw blade having a second tooth with a distal tip, the second tooth bent towards the first saw blade and the distal tip of the second tooth aligned with a centerline between the two distal tips of the first tooth.

Abstract: Methods, systems and devices are provided for facilitating a surgical procedure on a knee, particularly, a revision total knee replacement procedure. Prior femoral and tibial prostheses are removed. A cut end of a distal femur is engaged with a femoral adjustment member, which will, typically center itself about an intermedullary rod placed into the femur. The lateral and medial, forces exerted by lateral and medial sides of the femoral adjustment member and the cut tibial plateau against each other are measured. The femoral adjustment member is adjusted to apply and/or adjust tension to the lateral collateral ligament and/or the medial, collateral ligament based on the measured forces, for example, such that the measured lateral force and the measured medial force are matched. Based on the position of the adjusted femoral member, guided clean-up cuts for placement of a new femoral prostheses are made on the cut end of the distal femur.

Abstract: A monolithic material including a first region having a first variability of strength and a second region joined to the first region, the second region having a second variability of strength, wherein the monolithic material has a variability of strength less than the first variability of strength of the first region and less than the second variability of strength of the second region.

Abstract: Systems for determining force balance on a knee joint during a surgical procedure are disclosed. A system can include a tibial prosthesis. The tibial prosthesis can include a bearing component, a base component, and a shim component. The bearing component can have a superior articulating surface and an inferior surface. The bearing component can include a top portion, a bottom portion, a frame disposed between the top portion and the bottom portion, and a plurality of sensors disposed between the frame and the bottom portion. The frame can have a plurality of apertures corresponding in size or shape to the plurality of sensors. The base component can have a superior surface and an inferior surface. The shim component can be configured to be slidable between the inferior surface of the bearing component and the superior surface of the base component in an anterior to posterior direction.

Abstract: Tibial prosthesis methods for balancing a knee joint during a surgical procedure are disclosed. A method can comprise inserting a first tibial shim component between a tibial bearing component and a tibial base or a tibial plate component in an anterior/posterior direction. The first tibial shim component can include one or both of a medial edge having a different height than a lateral edge or an anterior edge having a different height than a posterior edge. The method can further comprise testing one or more of a stability, a force balance, or a range of motion of a knee joint in which the first tibial shim component is inserted. If the testing result is not satisfactory, the method can include removing the first tibial shim component, and inserting a second tibial shim component between the tibial bearing component and the tibial base or tibial plate component in the anterior/posterior direction.

Abstract: A method for positioning a bone cutting guide on a tibia may involve coupling a cutting guide positioning apparatus with a tibia, adjusting the positioning apparatus in a varus/valgus orientation, adjusting the positioning apparatus in an anterior/posterior orientation, adjusting the positioning apparatus up or down to select a tibial bone resection level, and contacting a cutting guide with the tibia, using the adjusted positioning apparatus.

Abstract: A device for performing a surgical procedure on a knee includes an adjustable femoral portion, a tibial portion and at least one sensor coupled with the femoral and/or tibial portions to sense pressure exerted by the femoral and tibial portions against one another. The femoral portion is adapted for removably coupling with a distal end of a femur to adjust tension in soft tissue adjacent the knee and has at least one positioning feature adapted to move relative to the distal end of the femur as the femoral portion is adjusted, thus helping position a femoral prosthetic on the distal end of the femur. The sensor(s) may be adapted to sense pressure at medial and lateral sides of the knee, and relative pressures may be displayed as data on a visual display. Adjustments to the femoral member may be made to balance pressure at flexion and extension of the knee.

Abstract: A device for performing a surgical procedure on a knee includes an adjustable femoral portion, a tibial. portion and at least one sensor coupled with the femoral and/or tibial portions to sense pressure exerted by the a moral and tibial portions against one another. The femoral portion is adapted for removably coupling with a distal end of a Femur to adjust tension in soft tissue adjacent the knee and has at least one positioning feature adapted to move relative to the distal end of the femur as the femoral portion is adjusted, thus helping position a femoral prosthetic on the distal end of the femur. The sensor(s) may he adapted to sense pressure at medial and lateral sides of the knee, and relative pressures may he displayed as data on a visual display. Adjustments to the femoral member may be made to balance pressure at flexion and extension of the knee.

Abstract: A surgical saw includes a shaft, a first saw blade mounted on the shaft, a second saw blade mounted on the shaft parallel to the first saw blade, the first saw blade having a first tooth having two distal tips, and the second saw blade having a second tooth with a distal tip, the second tooth bent towards the first saw blade and the distal tip of the second tooth aligned with a centerline between the two distal tips of the first tooth.

Abstract: A system is provided for positioning a cutting guide on a femur of a knee to make a cut along a distal end of the femur during knee surgery. The system may generally include an adjustable femoral attachment member configured to attach to a cut distal end of the femur, a cutting guide removably attachable to the femoral attachment member and configured to guide a surgical saw to make an additional cut on the distal end of the femur, and a force sensor for positioning between the femoral attachment member and a proximal end of a tibia of the knee. The force sensor may include a medial portion for sensing a medial force in the knee and a lateral portion for sensing a lateral force in the knee.

Abstract: A method for positioning a bone cutting guide on a tibia may begin with coupling a bone cut positioning apparatus with a tibia. The method may also include adjusting the positioning apparatus in a varus/valgus orientation to shine a light emitted by a light emitter approximately along a midline of an anterior surface of the tibia, swinging a pivoting arm about a pivot joint to direct the emitted light along a medial surface of the tibia, adjusting the positioning apparatus in an anterior/posterior orientation to shine the light approximately along a midline of the medial surface, contacting a stylus with a proximal end of the tibia to select a cutting depth for a bone cut to be made on the tibia, and attaching the bone cutting guide to the tibia in a position determined by the positioning apparatus.

Abstract: Systems, devices, and methods are provided for measuring forces in the space of a knee during surgery. Such forces can be caused by tension in the ligaments of the knee. A femoral member is engaged with a distal femur. While the knee is flexed, partially extended, or fully extended, a force sensor and a gauge shim can be placed in the gap between the femoral member and the tibial plateau to measure the forces therebetween. The force sensor provides an accurate and quantifiable measurement of force, making knee replacement surgery and ligament tension balancing more accurate, standardized and repeatable. The force sensor comprises an elongate housing which comprises a thin force sensing distal portion and a proximal handle portion.