Abstract: A method for re-registration between a robotic coordinate system and an image data set is provided. The inventive re-registration method includes the steps of providing an image data set that has been registered within a robotic coordinate system based on an initial bone position; locating a first conserved point and a line segment that is fixed relative to the initial bone position prior to any detectable change in bone position from the initial bone position; relocating the first conserved point and at least a portion of the line segment after bone motion may have occurred to determine the locational change in the first conserved point and the line segment; and re-registering the image data set within the robotic coordinate system based on the determined locational changes. A system for performing this method is also provided.

Abstract: A cutting device is provided that includes an expandable tube having a base and a hollow interior for receiving the implant therein. The expandable tube includes cutting segments extending from the base and terminating to form a distal end of the expandable tube. At least one of the cutting segments has a cutting end with cutting teeth at the distal end of the expandable tube. Spring shaped sections are provided that extend the cutting segments. A method for removing an implant from a target bone is also provided based on the cutting device. A system for removing material directly surrounding an outer surface of an implant in an intramedullary canal of a target bone is also provided based on the cutting device and a sheath. A retractable opening is formed of leaflets at a distal end of the sheath, and a proximal end opposite the distal end.

Abstract: A system and method of use thereof are provided for dynamically generating an environmental map for use in robotic assisted surgery. The generated environmental map is used to plan a recovery tool path that an end-effector tool can safely and efficiently follow to re-position the tool back to a cutting position following the displacement of the tool from the cutting position. Additionally, the environmental map is used to update a virtual representation of a bone to provide a user with visual feedback as to the progression of the end-effector tool as the tool removes material from the bone during a surgical procedure.

Abstract: A saw guide for guiding a surgical saw or drill includes a guide portion having one or more guide slots, the one or more guide slot or hole configured to guide a surgical saw or drill. The guide portion has an attachment portion forming a clamping slot between the guide portion and the attachment portion. A clamp locking mechanism is assembled to the guide portion and has one or more cams in contact with the attachment portion. An alignment system for surgical bone cutting procedures is provided that includes bone pins inserted within a virtual plane relative to a cut plane to be created on a subject's bone. One of the aforementioned guides is configured to be received onto the bone pins, one or more guide slots within said guide, said one or more guide slots configured to guide a surgical saw to make surgical cuts on the subject's bone.

Abstract: A method and system is provided for registering the position and orientation (POSE) of a bone, where only data points that rest on the cortex of the bone are used to establish data points for determining the bone's POSE during a surgical procedure. The method collects the contact force and only collects a data point upon the removal at a specific threshold, which allows a digitizer to pass through the cartilage or soft tissue prior to the condition which defines when a data collection switch is closed. The collection of points is more consistent since the threshold value is normalized to hounds-field units of computed tomography (CT) data used for segmentation. The method utilizes a load cell to define a selection of a point based upon the release of what the point load applied is, as well as normalizing the activation threshold to the CT data of the bone.

Abstract: A system and process is provided for dynamically positioning or repositioning a robot in a surgical context based on workspace and task requirements, manipulator requirements, or user preferences to execute a surgical plan. The system and method accurately determines and indicates an optimal position for a robot with respect to a patient's anatomy before or during a surgical procedure. Optimal positions for a robot are intuitively indicated to a user. surgical procedures can illustratively include surgery to the knee joint, hip joint, spine, shoulder joint, elbow joint, ankle joint, jaw, a tumor site, joints of the hand or foot, and other appropriate surgical sites.

Abstract: A computerized system and method is provided for stabilizing a first bone relative to a second bone during robotic based total joint arthroplasty. A plurality of cut paths are determined, either pre-operatively or intra-operatively using three-dimensional (3-D) virtual bone models, relative to the first bone and/or second bone in order to modify the bone(s) to receive an implant in a desired position and orientation. At least one stability region is identified between the two bones, where one or more cut paths are adjusted to avoid the at least one stability region. The first bone is therefore stabilized against the second bone at the at least one stability region while the remaining cut paths are executed around the stability region. Finally, the at least one stability region is removed once the reaming cut paths are completed and an implant is placed on the modified bone(s).

Abstract: A method for registering one or more surfaces associated with a bone for implant revision procedures includes a digitizer used to digitize surface points on remaining cement, bone surfaces, or both. The bone is adapted to hold a primary implant and from which the primary implant was removed. The position of the one or more surfaces associated with bone is registered by computing at least one of: a generic set of one or more planes using the surface points or a best match between a known implant geometry and the surface points. A computer-assisted surgical system is also provided to execute the method.

Abstract: A rollable digitizer device for collecting a plurality of points on a bone that includes a wheel having multiple probes emanating circumferentially therefrom. One or more contact sensors adapted to detect if at least one of probes is in contact with the bone. The contact sensors located in the wheel, on the wheel, proximal to said one or more contact sensors, or a combination thereof. A handle connected to the wheel and adapted to permit a user to roll the probes along the bone, so each of the probes make sequential and detectable contact with the bone to facilitate the collection of multiple points on the bone. A method for collecting a multiple registration points on a bone with the rollable digitizer device includes wielding the rollable digitizer by the handle. The probes are rolled along the surface of the bone to collect the plurality of registration points.

Abstract: Described herein are systems and methods for creating a custom registration guide. In general, the methods may include receiving scan data of a patient's bone; creating instructions based on the scan data for creating a three-dimensional surface model of the patient's bone; and moving a plurality of moveable elements, coupled to the adjustable model, based on the instructions. The method may further include the steps of placing a malleable registration guide onto the adjustable model and shaping the registration guide to fit to the adjustable model. The method may further include the step of intraoperatively determining the location of a patient's bone using the custom registration guide. The step of determining the location of the patient's bone may include the steps of coupling the registration guide and fiducial markers to the patient's bone.

Abstract: A process for confirming registration of bones involved in a joint replacement procedure is provided that includes a three dimensional (3-D) models of the bones being generated. The bones are tracked with a tracking device attached to each of the bones to allow 6-degrees of freedom (DOF) tracking during the joint replacement procedure. The 3-D models to the bones are registered and the bones having the tracking device are moved. A corresponding motion in the 3-D models with the moving of the bones is then observed. The registration of the 3-D models to the bone when the observations of the 3-D models move in correspondence with the actual bones is then confirmed or an alarm when an algorithm detects the 3-D bone models move unexpectedly during the movement of the bones. A system for confirming registration of bones involved in the joint replacement procedure is also provided.

Abstract: A method for removing an implant attached to a bone during revision joint replacement surgery includes a library of implant models. A series of surface points are collected on the implant with a digitizer. A best match is computed between the collected surface points and an implant model in the library of implant models to register the position of the implant model to the implant. A location is computed of a material-implant interface based on the geometry of the implant model and the registered position of the implant model. Material is removed at the material-implant interface to separate the implant from the bone. A computer-assisted surgical system is provided for performing the method.

Abstract: A method for registering a bone is provided that includes the installation of two or more registration markers on an exposed portion of the bone as part of a first stage of a revision. An image data set of the bone is generated to create imaged registration markers. A surgical plan is generated for implanting one or more secondary implants in a second stage of the two-stage procedure based on the image data. The bone is registered to the surgical plan and a computer-assist device using the two or more registration markers by: digitizing a set of positions of the two or more registration markers to create digitized registration markers; and mapping the set of positions of the digitized registration markers with a corresponding set of positions of the imaged registration markers. A system for performing the method is provided. Implant revision is promoted through the use of the method.

Abstract: A method for removing an implant attached to a bone during revision joint replacement surgery includes a library of implant models. A series of surface points are collected on the implant with a digitizer. A best match is computed between the collected surface points and an implant model in the library of implant models to register the position of the implant model to the implant. A location is computed of a material-implant interface based on the geometry of the implant model and the registered position of the implant model. Material is removed at the material-implant interface to separate the implant from the bone. A computer-assisted surgical system is provided for performing the method.

Abstract: A method for implantation of non-spherical or asymmetric implants is provided that includes devising a pre-surgical plan with pre-operative planning software operating on a computer to define at least one shape, orientation, type, size, geometry, or placement of an implant having at least a head component or a cup component in, on, or relative to an operative bone of a subject, the head component or the cup having at least two cross-sectional radii of different dimensions in, on, or relative to an operative bone of a subject. A computer-assisted surgical device is used to place the implant. The implant is positioned in, on, or relative to the bone by the computer-assisted surgical device in accordance with the pre-surgical plan. A system for devising a pre-surgical plan for the implant, and positioning the implant in, on, or relative to a bone in accordance with the pre-surgical plan is also provided.

Abstract: A process for confirming registration of bones involved in a joint replacement procedure is provided that includes a three dimensional (3-D) models of the bones being generated. The bones are tracked with a tracking device attached to each of the bones to allow 6-degrees of freedom (DOF) tracking during the joint replacement procedure. The 3-D models to the bones are registered and the bones having the tracking device are moved. A corresponding motion in the 3-D models with the moving of the bones is then observed. The registration of the 3-D models to the bone when the observations of the 3-D models move in correspondence with the actual bones is then confirmed or an alarm when an algorithm detects the 3-D bone models move unexpectedly during the movement of the bones. A system for confirming registration of bones involved in the joint replacement procedure is also provided.

Abstract: A robotic system includes a base with a manipulator is attached to the base. At least one sensor is associated with the manipulator. The at least one sensor detects a trajectory of an external disturbance on the manipulator or an external cue from a user. A controller is provided that converts the trajectory detected by the at least one sensor to an input signal or the external cue detected by the at least one sensor to an input signal. A drive system receives the input signal, and in response to the input signal powers the base or to power the base in a trajectory corresponding to the external cue. A method for intuitive motion control of the robotic system is also provided.

Abstract: Systems and methods for monitoring an operative site during a surgical procedure using a computer controlled surgical device. In general, the methods include the steps of processing one or more defined cutting paths having one or more cut regions; determining a correlation between the cut region and one or more critical regions to generate an alert, wherein the alert indicates a movable end-effector is within a defined proximity of the critical region; and requiring a user acknowledgment of the alert to allow processing of the cutting path to continue. Also described herein are systems and methods for minimizing user fatigue during a semi-computer controlled surgical procedure. In general, the methods includes the step of requiring a user generated acknowledgment in response to a computer generated alert, wherein the user acknowledgment is generated using a user controller, the user controller being minimally intrusive to the user experience.

Abstract: A method and system are provided to determine an optimal placement with respect to position and orientation for one or more bones in a workspace of a robot to improve robotic cutting and maximize the robot workspace during a robotic surgical procedure. The method is additionally useful to aid a user in positioning and orienting the bones in the operating room at the determined position and orientation.