A method for intraoperatively measuring joint contact mechanics of a patient's joint is provided. The method includes inserting a sensor between first and second bones of a joint. Then a predetermined force is applied to one of the first and second bones. Afterwards, contact mechanics such as, contact stresses, contact areas and/or forces are measured between the first and second bones in response to the applied predetermined force.

A knee arthroplasty instrument may include a tensioning instrument and at least a first sensor. The tensioning instrument can optionally include a tibial component configured to engage the tibia and a femoral component configured to engage the femur. The femoral component can be movably coupled to the tibial component to place the knee joint in tension by separating the tibia and the femur. The first sensor can be coupled to the tensioning instrument and can be configured to collect first data regarding a torque of the tensioning instrument when separating the tibia and the femur.

A method for intraoperatively measuring joint contact mechanics of a patient's joint is provided. The method includes inserting a sensor between first and second bones of a joint. Then a predetermined force is applied to one of the first and second bones. Afterwards, contact mechanics such as, contact stresses, contact areas and/or forces are measured between the first and second bones in response to the applied predetermined force.

A system and method for improving installation of a prosthesis, particularly an acetabular cup. The system and method may include implementation of a constant velocity relative motion between a prosthesis and an installation site. For example, an installation system may be fixed relative to the installation site, with the prosthesis fixed into an initial position. The prosthesis is moved at constant speed (i.e., with minimal if any acceleration or applied impulses) relative to the installation site. That is, one or both of the prosthesis or the installation site may be in motion. Resistive forces to installation of a prosthesis may thus be reduced by maintaining the prosthesis constantly in motion relative to the installation site. Securing a processing/implanting tool directly to the installation site may offer advantages.

A surgical robot system includes a surgical robot having a robot base and a robot arm connected to the robot base. The surgical robot system further includes a joint manipulation arm configured to be attached to the robot arm and to be connected to an appendage of a patient and moved to apply force and/or torque to a joint connecting the appendage through movement of the robot arm. The surgical robot system further includes force and/or torque sensor apparatus configured to output a feedback signal providing an indication of an amount of force and/or torque that is being applied to the robot arm and/or the joint manipulation arm. At least one controller is configured to determine ligaments balancing at the joint based on a plurality of measurements of the feedback signal, and to output information characterizing the ligaments balancing.

An adjustable spinal fusion intervertebral implant is provided that can comprise upper and lower body portions that can each have proximal and distal wedge surfaces disposed at proximal and distal ends thereof. An actuator shaft disposed intermediate the upper and lower body portions can be actuated to cause proximal and distal protrusions to converge towards each other and contact the respective ones of the proximal and distal wedge surfaces. Such contact can thereby transfer the longitudinal movement of the proximal and distal protrusions against the proximal and distal wedge surfaces to cause the separation of the upper and lower body portions, thereby expanding the intervertebral implant. The upper and lower body portions can have side portions that help facilitate linear translational movement of the upper body portion relative to the lower body portion.

An adjustable spinal fusion intervertebral implant is provided that can comprise upper and lower body portions that can each have proximal and distal wedge surf aces disposed at proximal and distal ends thereof. An actuator shaft disposed intermediate the upper and lower body portions can be actuated to cause proximal and distal protrusions to converge towards each other and contact the respective ones of the proximal and distal wedge surfaces. Such contact can thereby transfer the longitudinal movement of the proximal and distal protrusions against the proximal and distal wedge surfaces to cause the separation of the upper and lower body portions, thereby expanding the intervertebral implant. The upper and lower body portions can have side portions that help facilitate linear translational movement of the upper body portion relative to the lower body portion.

An adjustable spinal fusion intervertebral implant is provided that can comprise upper and lower body portions that can each have proximal and distal wedge surf aces disposed at proximal and distal ends thereof. An actuator shaft disposed intermediate the upper and lower body portions can be actuated to cause proximal and distal protrusions to converge towards each other and contact the respective ones of the proximal and distal wedge surfaces. Such contact can thereby transfer the longitudinal movement of the proximal and distal protrusions against the proximal and distal wedge surfaces to cause the separation of the upper and lower body portions, thereby expanding the intervertebral implant. The upper and lower body portions can have side portions that help facilitate linear translational movement of the upper body portion relative to the lower body portion.

An adjustable spinal fusion intervertebral implant is provided that can comprise upper and lower body portions that can each have proximal and distal wedge surf aces disposed at proximal and distal ends thereof. An actuator shaft disposed intermediate the upper and lower body portions can be actuated to cause proximal and distal protrusions to converge towards each other and contact the respective ones of the proximal and distal wedge surfaces. Such contact can thereby transfer the longitudinal movement of the proximal and distal protrusions against the proximal and distal wedge surfaces to cause the separation of the upper and lower body portions, thereby expanding the intervertebral implant. The upper and lower body portions can have side portions that help facilitate linear translational movement of the upper body portion relative to the lower body portion.

In an artificial limb system having an actuator coupled to a joint for applying a torque characteristic thereto, a control bandwidth of a motor controller for a motor included in the actuator can be increased by augmenting a current feedback loop in the motor controller with a feed forward of estimated back electromotive force (emf) voltage associated with, the motor. Alternatively, the current loop is eliminated and replaced with a voltage loop related to joint torque. The voltage loop may also be augmented with the feed forward of estimated back emf, to improve the robustness of the motor controller.