Patent Description:
During a surgical procedure, a patient is often positioned on an operating table or in a chair. Whether due to normal bodily functions (including voluntary and involuntary processes and/or reactions) or external stimuli such as surgical intervention, one or more anatomical features of the patient may move relative to the operating table or chair, relative to another external reference, and/or relative to another anatomical feature.

Surgical procedures may involve the use any number of surgical tools, including tools configured for cutting, grinding, roughing, cleaning, and otherwise interacting with soft and/or hard tissue, as well as tools configured for use with implant insertion. Such tools may be, for example, held and manipulated by a surgeon, held by a passive mechanical fixture or a robotic arm while being manipulated by a surgeon, held and manipulated by a robotic arm controlled by a surgeon, or held and manipulated by a robotic arm under autonomous control.

<CIT> discloses bone clamp for stabilizing cervical vertebrae, having coupling portion for pivotally coupling sublaminar and dorsal jaws, and securing portion for securing screw that connects to sublaminar and dorsal jaws.

The present invention relates to a spinal stabilization system as claimed hereafter. Preferred embodiments of the invention are set forth in the dependent claims.

A first one of the plurality of anchors may have a first height, and a second one of the plurality of anchors has a second height different than the first height.

A first one of the plurality of anchors may have a first height less than <NUM>, and a second one of the plurality of anchors has a second height greater than or equal to <NUM>.

Each anchor may further comprise a spring that biases the clamp toward the fully closed position.

The clamp may comprise: a first contact surface opposite and facing a second contact surface; and a plurality of teeth on at least one of the first contact surface and the second contact surface, the plurality of teeth configured to prevent movement of the clamp relative to the anatomical element when the clamp is engaged with the anatomical element.

One of the bridge interface and the anchor interface may be a ball, and the other of the bridge interface and the anchor interface may be a socket.

The bridge interface may further comprise a lock configured to selectively prevent movement of the bridge relative to the anchor when the anchor interface is received by the bridge interface.

At least one anchor of the plurality of anchors may comprise a tracking marker.

At least one anchor of the plurality of anchors may comprise two bridge interfaces.

The at least one bridge may be a plurality of bridges, and a first bridge of the plurality of bridges may have a first length different than a second length of a second bridge of the plurality of bridges.

An anatomical stabilization system comprising an anchor. The anchor comprises: a clamping mechanism for securing the anchor to an anatomical feature and comprising first and second contact surfaces, each having a non-slip feature; a lock configurable to prevent release of the clamping mechanism from the anatomical feature; at least one bridge receptacle; and a tracking marker.

Further comprising: a bridge comprising a rigid elongate member with a first end opposite a second end, the first end configured to be received by the at least one bridge receptacle.

Wherein the bridge comprises a photoelastic material.

Further comprising a plurality of anchors and a plurality of bridges.

Further comprising an adaptor for securing the second end of the bridge to a surgical robot, an operating table, or a bed.

Wherein the clamping mechanism is configured to be secured to a plurality of anatomical features simultaneously.

The tracking marker may be an optical tracking marker or an electromagnetic tracking marker.

A not claimed method of tracking anatomical movement, comprising: receiving first sensor information corresponding to a first pose, at a first time, of an anchor attached to an anatomical element via a clamp, the anchor comprising a tracking marker; receiving second sensor information corresponding to a second pose, at a second time after the first time, of the anchor; determining an initial pose of the anatomical element based at least in part on the first sensor information; determining an updated pose of the anatomical element based at least in part on the second sensor information; and comparing the updated pose to the initial pose to identify movement of the anatomical element from the first time to the second time.

Further comprising: receiving strain information corresponding to a detected strain in a bridge made of photoelastic material and fixedly secured to the anchor; and causing a strain value to be displayed on a user interface, the strain value based at least in part on the strain information.

The tracking marker may be a passive tracking marker.

References to "embodiments" throughout the description which are not under the scope of the appended claims merely represent possible exemplary executions and are therefore not part of the present invention.

It should also be understood that, depending on the example or embodiment, certain acts or events of any of the processes or methods (not claimed) described herein may be performed in a different sequence, may be added, merged, or left out altogether (e.g., all described acts or events may not be necessary to carry out the techniques). In addition, while certain aspects of this disclosure are described as being performed by a single module or unit for purposes of clarity, it should be understood that the methods of this disclosure may be performed by a combination of units or modules associated with, for example, a computing device and/or a medical device (including a medical imaging device).

In one or more examples, one or more steps of the not claimed described methods, processes, and techniques may be implemented in hardware, software, firmware, or any combination thereof.

Instructions may be executed by one or more processors, such as one or more digital signal processors (DSPs), general purpose microprocessors (e.g., Intel Core i3, i5, i7, or i9 processors; Intel Celeron processors; Intel Xeon processors; Intel Pentium processors; AMD Ryzen processors; AMD Athlon processors; AMD Phenom processors; Apple A10 or 10X Fusion processors; Apple A11, A12, A12X, A12Z, or A13 Bionic processors; or any other general purpose microprocessors), application specific integrated circuits (ASICs), field programmable logic arrays (FPGAs), or other equivalent integrated or discrete logic circuitry.

Also, unless explicitly stated otherwise, terms such as "about" and "approximately" when used in connection with a stated value mean within ten percent of the stated value.

Embodiments of the present disclosure may be useful for any not claimed surgical procedure. Robotic and navigation system used in surgery may require patient reference or fixation systems relative to the patient's bony anatomy. During spine surgery, to take just one example, segmental motion of vertebrae may reduce guidance accuracy when using guided stereotactic systems such as robotics or navigation. (A segment is an individual bone capable of moving in relation to adjacent bones. ) Such motion may result from the application of force, and may reduce guidance and/or navigation accuracy. Bone-mounted platforms or other anchors connected to the spinal anatomy and to the reference system may be used for restraining such relative motion. Bone-mounted platforms or other anchors may include spinous process clamps or pins, PSIS pins and bridge-type instruments. The reference system may include one or more navigation references and/or table mounted robotic systems.

A mechanically linked multi-anchor fixation system according to at least one embodiment of the present disclosure is directly attached to multiple bony structures, thus restraining segmental movement and reflecting the average motion of the segment of interest.

Each individual anchor may be or comprise a clamp designed for single/multiple spinal process attachment, a percutaneous pin designed for pelvic attachment, a percutaneous pin designed for spinous process attachment with or without a positive stop; and/or a fixation system designed to connect to existing hardware such as screws or rods in revision cases with previously implemented hardware.

The mechanical link between anchors may be, in some embodiments, a single radiolucent bridge or a series of small radiolucent bridges designed to mechanically restrain neighboring anchors in varying orientations to allow fixation to deformed or rotated spine potentially through a series of ball and socket joints.

The apparatus may be attached to the operating table (table fixation) for additional anatomy-to-table stabilization.

In some embodiments, the apparatus may be attached to a soft tissue retractor system for further stabilization.

The apparatus may serve as a patient attachment for navigation reference and/or for a robotic system. The apparatus may also include reusable instruments and/or sterile disposable instruments.

In some embodiments, the apparatus may contain force/torque sensors that can be used by a navigation system or a robotic system to refine mechanical positioning or position indication or to generate an alert upon detection of excessive motion and/or force.

Turning first to <FIG>, a block diagram of a system <NUM> is shown. The system <NUM> may be used, for example, to carry out a surgical procedure, to detect objects (including, for example, one or more tracking markers on one or more anchors) in a volume of interest, to update a surgical plan based on one or more detected objects, to execute a surgical plan, to carry out one or more steps or other aspects of one or more of the methods disclosed herein, and/or for any other useful purpose. The system <NUM> comprises a computing device <NUM>, one or more sensors <NUM>, a robot <NUM>, a navigation system <NUM>, a database <NUM>, and a cloud <NUM>. Notwithstanding the foregoing, systems according to other embodiments of the present disclosure may omit any one or more of the one or more sensors <NUM>, the robot <NUM>, the navigation system <NUM>, the database <NUM>, and/or the cloud <NUM>.

The computing device <NUM> comprises a processor <NUM>, a communication interface <NUM>, a user interface <NUM>, and a memory <NUM>. A computing device according to other embodiments of the present disclosure may omit one or both of the communication interface <NUM> and the user interface <NUM>.

The processor <NUM> of the computing device <NUM> may be any processor described herein or any similar processor. The processor <NUM> may be configured to execute instructions stored in the memory <NUM>, which instructions may cause the processor <NUM> to carry out one or more computing steps utilizing or based on data received, for example, from the sensor <NUM>, the robot <NUM>, the navigation system <NUM>, the database <NUM>, and/or the cloud <NUM>.

The computing device <NUM> may also comprise a communication interface <NUM>. The communication interface <NUM> may be used for receiving image or other data or other information from an external source (such as the sensor <NUM>, the robot <NUM>, the navigation system <NUM>, the database <NUM>, the cloud <NUM>, and/or a portable storage medium (e.g., a USB drive, a DVD, a CD)), and/or for transmitting instructions, images, or other information to an external system or device (e.g., another computing device <NUM>, the sensor <NUM>, the robot <NUM>, the navigation system <NUM>, the database <NUM>, the cloud <NUM>, and/or a portable storage medium (e.g., a USB drive, a DVD, a CD)). The communication interface <NUM> may comprise one or more wired interfaces (e.g., a USB port, an ethernet port, a Firewire port) and/or one or more wireless interfaces (configured, for example, to transmit information via one or more wireless communication protocols such as <NUM>. 11a/b/g/n, Bluetooth, NFC, ZigBee, RF, GSM, LTE, and so forth). In some examples, the communication interface <NUM> may be useful for enabling the device <NUM> to communicate with one or more other processors <NUM> or computing devices <NUM>, whether to reduce the time needed to accomplish a computing-intensive task or for any other reason.

The user interface <NUM> may be or comprise a keyboard, mouse, trackball, monitor, television, touchscreen, button, joystick, switch, lever, and/or any other device for receiving information from a user and/or for providing information to a user of the computing device <NUM>. The user interface <NUM> may be used, for example, to receive a user selection or other user input in connection with any step of any method described herein; to receive a user selection or other user input regarding one or more configurable settings of the computing device <NUM> and/or of another component of the system <NUM>; to receive a user selection or other user input regarding a desired movement of the robot <NUM>; and/or to receive a user selection or other user input regarding a surgical objective; to receive a user selection or other user input regarding a modification to a surgical plan. Notwithstanding the inclusion of the user interface <NUM> in the system <NUM>, the system <NUM> may automatically (e.g., without any input via the user interface <NUM> or otherwise) carry out one or more, or all, of the steps of any not claimed method described herein.

Although the user interface <NUM> is shown as part of the computing device <NUM>, in some examples, the computing device <NUM> may utilize a user interface <NUM> that is housed separately from one or more remaining components of the computing device <NUM>. In some embodiments, the user interface <NUM> may be located proximate one or more other components of the system <NUM>, while in other examples, the user interface <NUM> may be located remotely from one or more components of the system <NUM>.

The memory <NUM> may be or comprise a hard drive, RAM, DRAM, SDRAM, other solid-state memory, any memory described herein, or any other tangible non-transitory memory for storing computer-readable data and/or instructions. The memory <NUM> may store instructions <NUM>, and/or any other information or data, useful for completing, for example, any step of the method <NUM> described herein. The memory <NUM> may store, one or more algorithms <NUM> (including, for example, a tracking marker detection algorithm, a feature recognition algorithm, an image processing algorithm) and/or one or more surgical plans <NUM> (each of which may be or comprise, for example, one or more models or other three-dimensional images of a portion of an anatomy of a patient). The instructions <NUM> and algorithms <NUM> may, in some examples, be organized into one or more applications, modules, packages, layers, or engines, and may cause the processor <NUM> to manipulate data stored in the memory <NUM> and/or received from another component of the system <NUM>.

The sensor <NUM> may be any sensor suitable for obtaining information about a surgical environment and/or about one or more objects (e.g., one or more anchors, anatomical features to which such anchors are attached, and/or bridges) in a working volume or other volume of interest. The sensor <NUM> may be or comprise, for example, a camera (including a visible light/optical camera, an infrared camera, a depth camera, or any other type of camera); a proximity sensor; and Doppler device; one or more lasers; a LIDAR device (e.g., a light detection and ranging device, and/or a laser imaging, detection, and ranging device); a scanner, such as a CT scanner, a magnetic resonance imaging (MRI) scanner, or an optical coherence tomography (OCT) scanner; an O-arm (including, for example, an O-arm 2D long film scanner), C-arm, G-arm, or other device utilizing X-ray-based imaging (e.g., a fluoroscope or other X-ray machine); sensors used for segmental tracking of the spine or of spinal elements; sensors used for vertebrae/implant location detection; an ultrasound probe; or any other imaging device suitable for obtaining images of a work volume or volume of interest. The sensor <NUM> may be operable to image one or more objects positioned within, proximate, or otherwise around the anatomical features of a patient. The sensor <NUM> may be capable of taking a 2D image or a 3D image to yield image data. "Image data" as used herein refers to the data generated or captured by an imaging device, including in a machine-readable form, a graphical form, and in any other form. In some examples, the sensor <NUM> may be capable of taking a plurality of 2D images from a plurality of angles or points of view, and of generating a 3D image by combining or otherwise manipulating the plurality of 2D images. In some examples, the system <NUM> may operate without the use of the sensor <NUM>.

The sensor <NUM> may be operable to image a work volume or volume of interest in real-time (e.g., to generate a video feed or live stream). In such embodiments, the sensor <NUM> may continuously provide updated images and/or updated image data to the computing device <NUM>, which may continuously process the updated images and/or updated image data as described herein in connection with the method <NUM>. In some embodiments, the sensor <NUM> may comprise more than one sensor <NUM>.

The sensor <NUM> may be configured to capture information at a single point in time (e.g., to capture a still image or snapshot at a point in time), or to capture information in real time (e.g., to capture video information and/or a live stream of sensed information). The sensor <NUM> may be located in or proximate a surgical environment, and positioned so as to be able to detect a surgical working field or volume of interest. The sensor <NUM> may be, for example, mounted on a robotic arm such as the robotic arm <NUM>, attached to a navigation camera (e.g., of a navigation system <NUM>), or otherwise positioned.

The robot <NUM> may be any surgical robot or surgical robotic system. The robot <NUM> may be or comprise, for example, the Mazor X™ Stealth Edition robotic guidance system. The robot <NUM> may comprise one or more robotic arms <NUM>. In some examples, the robotic arm <NUM> may comprise a first robotic arm and a second robotic arm. In other examples, the robot <NUM> may comprise one robotic arm, two robotic arms, or more than two robotic arms. The robotic arm <NUM> may, in some examples, hold or otherwise support the sensor <NUM>. The robotic arm <NUM> may, in some examples, assist with a surgical procedure (e.g., by holding a tool in a desired trajectory or pose and/or supporting the weight of a tool while a surgeon or other user operates the tool, or otherwise) and/or automatically carry out a surgical procedure. In some examples, the system <NUM> may operate without the use of the robot <NUM>.

The navigation system <NUM> may provide navigation for a surgeon and/or a surgical robot during an operation. The navigation system <NUM> may be any now-known or future-developed navigation system, including, for example, the Medtronic StealthStation™ S8 surgical navigation system. The navigation system <NUM> may include a camera or other sensor(s) for tracking one or more reference markers, navigated trackers, or other objects within an operating room or other room where a surgical procedure takes place. In various examples, the navigation system <NUM> may be used to track a position of the sensor <NUM> (or, more particularly, of a navigated tracker attached, directly or indirectly, in fixed relation to the sensor <NUM>), and/or of the robot <NUM> (or one or more robotic arms <NUM> of the robot <NUM>), and/or of any other object in a surgical environment. The navigation system <NUM> may include a display for displaying one or more images from an external source (e.g., the computing device <NUM>, sensor <NUM>, or other source) or a video stream from the camera or other sensor of the navigation system <NUM>. In some examples, the system <NUM> may operate without the use of the navigation system <NUM>.

In some examples, one or more tracking or reference markers (i.e., markers detectable by the sensor <NUM> and/or by the navigation system <NUM>) may be placed on the robot <NUM>, the robotic arm <NUM>, an anchor or bridge as described herein, or any other object in the surgical space. The reference markers may be tracked by the navigation system <NUM>, and the results of the tracking may be used by the robot <NUM> and/or by an operator of the system <NUM> or any component thereof. In some examples, the navigation system <NUM> can be used to track other components of the system <NUM> (e.g., the sensor <NUM>) and the system can operate without the use of the robot <NUM> (e.g., with a surgeon manually manipulating, based on guidance from the navigation system <NUM>, any object useful for carrying out a surgical procedure).

The database <NUM> may store image data generated by one or more sensors <NUM> and may be configured to provide such image data (e.g., electronically) to the computing device <NUM> (e.g., for display on or via a user interface <NUM>, or for use by the processor <NUM> in connection with any method described herein) or to any other device, whether directly or via the cloud <NUM>. In some examples, the database <NUM> may be or comprise part of a hospital image storage system, such as a picture archiving and communication system (PACS), a health information system (HIS), and/or another system for collecting, storing, managing, and/or transmitting electronic medical records including image data. The database <NUM> may store any of the same information stored in the memory <NUM> and/or any similar information. In some examples, the database <NUM> may contain a backup or archival copy of information stored in the memory <NUM>.

The cloud <NUM> may be or represent the Internet or any other wide area network. The computing device <NUM> may be connected to the cloud <NUM> via the communication interface <NUM>, using a wired connection, a wireless connection, or both. In some examples, the computing device <NUM> may communicate with the database <NUM> and/or an external device (e.g., a computing device) via the cloud <NUM>.

Turning now to <FIG>, an anchor <NUM> and an anchor <NUM> according to embodiments of the present disclosure will be described. The anchor <NUM> and the anchor <NUM> are substantially similar to each other, although the anchor <NUM> is taller than the anchor <NUM>, which in turn is shorter than the anchor <NUM>. Each anchor <NUM> and <NUM> may be made of metal, a metal alloy, plastic, polyetheretherketone (PEEK), any biocompatible material, and/or any combination of any of the foregoing.

The anchor <NUM> comprises a body <NUM> with a head <NUM> and an arm <NUM>. The body <NUM> may be integrally fashioned of a single piece of a material, or may comprise an assembly of multiple components (e.g., the head <NUM> may be fashioned separately from and subsequently attached to the arm <NUM>). The anchor <NUM> further comprises a rotatable foot <NUM>, an arm <NUM>, a locking screw <NUM>, a plurality of bridge interface set screws <NUM>, and a bridge interface or receptacle <NUM>.

The head <NUM> comprises a tracking marker <NUM>, which may be provided directly on the head <NUM> or attached to the head <NUM>. The tracking marker <NUM> may be or comprise a geometric shape (as here, where the tracking marker <NUM> comprises a square), a geometric pattern (such as, for example, a UPC or QR code), one or more specific contours, one or more colors, one or more reflective spheres, one or more LEDs, or any other marker detectable by a sensor (e.g., a sensor <NUM> and/or a sensor of a navigation system <NUM>) that may be used to determine a pose (e.g., position and orientation) of the anchor <NUM>. The tracking marker <NUM> may be an optical tracking marker or an electromagnetic tracking marker. In some embodiments, such as with the anchors <NUM> or <NUM> illustrated in <FIG>, the tracking marker <NUM> or <NUM> may be passive and unpowered. In other embodiments, the tracking marker <NUM> or <NUM> may be active and powered, for example using a battery provided in the body <NUM> or <NUM> or elsewhere in the anchor <NUM> or <NUM>, respectively.

The head <NUM> also comprises one or more bridge interfaces or receptacles <NUM>, and a corresponding number of set screw apertures <NUM>. In the embodiment illustrated in <FIG>, the head <NUM> comprises two bridge interfaces <NUM>, positioned on opposite sides of the head <NUM>, and two set screw apertures <NUM>. The set screw apertures <NUM> extend from an upper surface of the head <NUM> into the bridge interfaces <NUM>, although in other embodiments the set screw apertures <NUM> may extend through a different surface of the head <NUM> into the bridge interfaces <NUM>.

The set screw apertures <NUM> are adapted to receive set screws <NUM>, which may be tightened against a bridge that extends into the bridge receptacle to prevent movement of the bridge relative to the anchor <NUM>. The set screw apertures <NUM> may comprise internal threads, and the set screws <NUM> may comprise external threads, such that the set screws <NUM> are configured to threadingly engage the set screw apertures <NUM>. Each set screw may comprise a drive <NUM> engageable by a tool (e.g., a screwdriver) to tighten and/or loosen the set screw <NUM> within the set screw aperture <NUM>.

In some embodiments, other mechanisms for locking a bridge in position relative to the anchor <NUM> may be used. For example, in some embodiments, the head <NUM> may comprise a slot extending therethrough, with one or more bolts, screws, or other fasteners engaging the head <NUM> and configured to adjust a width of the slot. In such embodiments, the slot may be opened (e.g., the width of the slot may be increased) to receive a bridge in the bridge interface <NUM>, after which the bolt(s), screw(s), or other fastener(s) used to adjust the width of the slot may be tightened to narrow or close the slot and cause the head <NUM> to tightly grip the portion of the bridge within the bridge interface <NUM>.

The bridge interfaces <NUM> of some anchors according to embodiments of the present disclosure may comprise one or more sensors configured to detected a position of a bridge within the bridge interface. For example, in some embodiments, an anchor interface of a bridge may be provided with a magnet, and a bridge interface of an anchor may comprise a magnetic sensor configured to detect a magnetic field. A wired or wireless interface may be used to transmit information from the magnetic sensor to, for example, a processor <NUM> of a computing device <NUM> for determination of a position of the bridge within the bridge interface of the anchor. Such information may be used, for example, to confirm or update a surgical plan, or in connection with generation or verification of a model of a patient anatomy, or for any other useful purpose.

The body <NUM> further comprises an arm <NUM>. The arm <NUM> extends from the head <NUM> and comprises at least one extension <NUM> comprises an aperture <NUM> for receiving a pin <NUM>. The at least one extension <NUM> may have a rounded outer surface to facilitate rotational movement of the arm <NUM> (described in more detail below) relative to the arm <NUM>. In other embodiments, however, the at least one extension <NUM> may have an outer surface without a rounded shape. As shown in <FIG>, the arm <NUM> includes two extensions <NUM>, extending parallel to each other from opposite sides of the arm <NUM>, such that the apertures <NUM> thereof are coaxial and able to receive the pin <NUM>.

The pin <NUM> may be made of metal, a metal alloy, plastic, PEEK, or any other material suitable for securing the arm <NUM> to the arm <NUM> and for withstanding the forces exerted thereon during use of the anchor <NUM>. The pin <NUM> may comprise a flange on one end thereof to stop the pin <NUM> from passing all the way through the aperture(s) <NUM>. Some or all of the pin <NUM> and one or more of the apertures <NUM> may be threaded to reduce a chance of the pin <NUM> falling out of the apertures <NUM> and thus disconnecting the arm <NUM> from the arm <NUM>. In other embodiments, the pin <NUM> may comprise a hole extending from an end thereof into which a locking pin may be inserted after the pin <NUM> has been inserted through the apertures <NUM>. In still other embodiments, once the pin <NUM> has been inserted into the apertures <NUM>, the previously un-flanged end of the pin <NUM> may be flanged to prevent the pin from moving axially within the apertures <NUM>.

A rotatable foot <NUM> is rotatably mounted to the arm <NUM> using a pin <NUM>. The pin <NUM> may comprise a smooth portion <NUM> around which the foot <NUM> is rotatable, and a threaded portion <NUM> that is configured to engage a corresponding threaded aperture within the arm <NUM> so as to secure the pin <NUM>, and the foot <NUM>, to the arm <NUM>. The pin <NUM> also comprises a flanged end to prevent the foot <NUM> from falling off of the pin <NUM> once secured to the arm <NUM>. The foot <NUM> is rotatably mounted to the arm <NUM> to enable the foot <NUM> to rotate as necessary to best engage an anatomical feature to which the anchor <NUM> is clamped.

The foot <NUM> comprises an aperture <NUM> extending therethrough and configured to receive the pin <NUM>. The foot <NUM> also comprises a contact surface <NUM>, from which a plurality of teeth <NUM> or other non-slip, grip-enhancing features extend. The contact surface <NUM> may be planar in some embodiments, as shown in <FIG>, while in other embodiments the contact surface <NUM> may be ridged or otherwise provided with integral grip-enhancing features. The contact surface may simply be an integral surface of the foot <NUM>, or the contact surface may be or comprise a plating or other cover attached to the foot <NUM> using glue or other adhesive, one or more mechanical fasteners (whether the teeth <NUM> or otherwise), or some other attachment method. In embodiments where the anchor <NUM> is sterilizable and reusable, the contact surface <NUM> (and, in some embodiments, the teeth <NUM>) may be removable and disposable, and configured to be replaced after each use.

A foot <NUM> as described herein may have a width adapted to engage only a single anatomical element (e.g., a spinous process of a single vertebra), or a width adapted to engage a plurality of anatomical elements simultaneously (e.g., a spinous process of multiple adjacent vertebrae).

The teeth <NUM> maybe made of the same material or a different material than the remaining portions of the foot <NUM>. The teeth <NUM> may be manufactured separately from one or more other portions of the foot <NUM>, or may be integrally fashioned as part of the foot <NUM> from a single piece of material. The teeth <NUM> may be permanently or removably installed in the foot <NUM>. The teeth <NUM> are configured to engage an anatomical feature to which the anchor <NUM> is clamped and prevent movement of the anchor <NUM> relative to the anatomical feature. To accomplish such engagement, the teeth <NUM> may comprise one or more points, ridges, serrations, non-slip surfaces, or other features for grabbing, gripping, engaging, or otherwise maintaining a secure attachment to the anatomical feature in question.

The anchor <NUM> further comprises an arm <NUM>, which comprises an elongate lever <NUM> and a foot <NUM>. An extension <NUM>, which may be the same as or similar to the extension <NUM> described above, extends from the lever <NUM>. An aperture <NUM> within the extension <NUM> receives the pin <NUM> when the anchor <NUM> is assembled, and enables the lever <NUM> to rotate around the pin <NUM> (which therefore acts as a fulcrum for the arm <NUM>).

The foot <NUM> of the arm <NUM> comprises a contact surface <NUM>, which may be the same as or similar to the contact surface <NUM> of the foot <NUM>. The foot <NUM> also comprises one or more teeth <NUM>, which are described above. The foot <NUM> and the foot <NUM> together engage an anatomical feature to which the anchor <NUM> is attached.

When the anchor <NUM> is assembled, the aperture <NUM> is aligned with the apertures <NUM> as well as an opening in the spring <NUM>, and the pin is then inserted through the apertures <NUM>, the aperture <NUM>, and the spring <NUM>. The spring <NUM> biases the clamp of the anchor <NUM> (comprising the arm <NUM>, the arm <NUM>, the foot <NUM>, and the foot <NUM>) toward a fully closed position. In other words, the spring <NUM> biases the contact surface <NUM> toward the contact surface <NUM>, thus generating a clamp force that helps to secure the anchor <NUM> to an anatomical feature. The embodiment of <FIG> utilizes a torsional spring <NUM>, but other embodiments may utilize other types of springs, configured as needed to bias the clamp of the anchor <NUM> into the closed position.

The anchor <NUM> also comprises a locking screw <NUM>, which comprises a threaded shaft <NUM> and an engagement head <NUM>. The threaded shaft <NUM> is adapted to be received by an internally threaded aperture <NUM> on the arm <NUM>, and the engagement head <NUM> is configured to press against the surface <NUM> of the lever <NUM>. As a result, by threading the locking screw <NUM> into the aperture <NUM> until the engagement head <NUM> contacts the surface <NUM>, the arm <NUM> can be prevented from rotating counterclockwise (e.g., to move the clamp of the anchor <NUM> into a fully open position, with the contact surfaces <NUM> and <NUM> separated by a maximum possible distance, given the other components of the anchor <NUM>). Moreover, by continuing to thread the locking screw <NUM> farther into the aperture <NUM> after the engagement head <NUM> makes contact with the surface <NUM>, the lever <NUM> may be forcibly rotated clockwise, thus increasing the clamp force exerted by the contact surfaces <NUM> and <NUM> on an anatomical feature (and increasing the effectiveness of the teeth <NUM>, which will more securely engage the anatomical feature as the clamping force increases. If no anatomical feature is positioned between the contact surfaces <NUM> and <NUM>, then the clamp may be moved to (and locked in) a fully closed position, in which the contact surfaces <NUM> and <NUM> are separated by a minimum possible distance (given the protrusion therefrom of the teeth <NUM>). To reduce the clamping force or release the clamp of the anchor <NUM> from the anatomical feature altogether, the locking screw <NUM> may unthreaded from the aperture <NUM>, thus enabling the arm <NUM> to be rotated in the counterclockwise direction around the pin <NUM> so as to move the contact surface <NUM> farther away from the contact surface <NUM>, with the effect of disengaging an anatomical feature gripped by the clamp.

The anchor <NUM> comprises a body <NUM>, a rotatable foot <NUM>, and an arm <NUM>. The anchor <NUM> also shares a number of features with the anchor <NUM>, which features are commonly numbered and described above.

The body <NUM> is substantially similar to the body <NUM> as described above. The head <NUM> is identical to the head <NUM> of the anchor <NUM> described above, but for a different tracking marker <NUM>, which allows the anchor <NUM> to be distinguished from the anchor <NUM> by a navigation system <NUM> or sensor <NUM> in a surgical setting. The arm <NUM> the shorter than the arm <NUM>, but comprises all of the same features of the arm <NUM> described above.

Similarly, the arm <NUM> is shorter than the arm <NUM>, but comprises all of the same features of the arm <NUM> described above. So too with the foot <NUM>, which is shaped differently than the foot <NUM> but comprises all of the same features of the foot <NUM> described above.

In addition to encompassing anchors of different heights, the present disclosure also encompasses embodiments comprising anchors of different sizes and dimensions (e.g., different widths, lengths, cross-sectional areas, contact surface area).

Anchors according to some embodiments of the present disclosure may have a height of less than five centimeters (cm), or between five and eight cm, or between eight and ten cm, or between nine and eleven cm, or less than ten cm, or greater than or equal to ten cm. Bridges according to embodiments of the present disclosure may have a length of more than one cm, or between one and five cm, or between five and ten cm, or between eight and twelve cm, or less than ten cm, or greater than or equal to ten cm.

The anchor <NUM> may be used and operated in the same manner as, or in a substantially similar manner to, the anchor <NUM>.

In some embodiments of the present disclosure, an anchor may comprise a head <NUM> secured to the shaft of a Shanz screw. Such anchors may be threaded into an anatomical feature (e.g., a pelvis, a vertebra) of a patient to secure the anchor to the anatomical feature, after which a one or more bridges may be connected to the head <NUM> as described elsewhere herein.

Turning now to <FIG>, a bridge <NUM> may be used to secure an anchor such as the anchor <NUM> or <NUM> (and thus the anatomical element(s) to which the anchor is secured) to an operating table, a robot, or another structure (e.g., a wall, ceiling, floor) via an adaptor <NUM>. Use of an adaptor <NUM> to so secure an anchor in this manner beneficially enables movement of the anatomical elements in question, relative to the operating table, robot, or other structure to which the adaptor <NUM> is connected, to be restrained or entirely prevented.

The bridge <NUM> comprises a rigid, elongate member <NUM> having a first end with a first anchor interface <NUM> and a second end with a second anchor interface <NUM>. The elongate member <NUM> may be made of any material described herein and may in some embodiments be manufactured of a radiolucent material. The rigid, elongate member may comprise a core material extending along an axis thereof and having a first rigidity, and an outer material surrounding the core material and having a second rigidity different than the first rigidity. Although shown as having a circular cross-section, the rigid, elongate member may in some embodiments comprise a non-circular cross-section, which may be, for example, a square cross-section, a rectangular cross-section, a triangular cross-section, a star-shaped cross-section, or any other cross-sectional shape.

The first anchor interface <NUM> is a ball, and is received by a bridge interface <NUM> of the adaptor <NUM>, which bridge interface <NUM> is in the form of a socket. The bridge interface <NUM> may be made of the same material as or a different material than the ball of the first anchor interface <NUM>, and may be designed to have some flexibility or play that enables a portion of the bridge interface <NUM> to give way as the ball of the first anchor interface <NUM> is inserted into the bridge interface <NUM>, and then to spring back into position to help secure the ball of the first anchor interface <NUM> within the bridge interface <NUM>. Use of a ball and socket as shown beneficially enables the bridge <NUM> to be positioned in any one of a plurality of possible positions relative to the adaptor <NUM>, as needed. Once the bridge <NUM> is properly positioned, the set screw <NUM> may be tightened against the anchor interface <NUM> of the bridge <NUM>.

The second anchor interface <NUM> of the bridge <NUM> comprises a different type of interface than the first anchor interface <NUM>. Specifically, the second anchor interface <NUM> comprises a slotted cylinder with a rounded flange extending from an end thereof. The two halves of the second anchor interface <NUM> (separated by the slot) are configured to bend toward each other when pressed into a corresponding bridge interface (e.g., on an anchor such as the anchor <NUM> or <NUM>), and then to spring back into position to prevent the second anchor interface <NUM> from falling out of or being easily removed from the corresponding bridge interface. A set screw such as the set screws <NUM> and <NUM> may be used to further secure the second anchor interface <NUM> into a corresponding bridge interface. Although the second anchor interface <NUM> is not configured to allow positioning of the bridge <NUM> at a variety of angles relative to the corresponding bridge interface, the second anchor interface <NUM> may permit rotation of the bridge <NUM> about an axis thereof relative to the corresponding bridge interface, which may be beneficial in some instances, including in particular in connection with a rotatable fixation bridge as described in <CIT>, the entirety of which is hereby incorporated by reference herein.

The rigid, elongate member <NUM> may support one or more attachments <NUM>, which may be used to maintain spacing between the elongate member <NUM> and one or more anatomical elements or other objects, or to support a surgical instrument or tool, or for any other useful purpose.

With reference to <FIG>, two bridges-a longer bridge <NUM> and a shorter bridge <NUM>-are illustrated. The bridges <NUM> and <NUM> are identical but for the rigid, elongate member <NUM> of the bridge <NUM> having a greater length than the rigid, elongate member <NUM> of the bridge <NUM>. Unlike the bridge <NUM>, the bridges <NUM> and <NUM> each comprise identical anchor interfaces at each end thereof-anchor interfaces <NUM> and <NUM> on the bridge <NUM> and anchor interfaces <NUM> and <NUM> on the bridge <NUM>. These anchor interfaces are all balls, configured to be received in corresponding sockets such as the bridge interface <NUM> described above in connection with the anchors <NUM> and <NUM>. However, other anchor interfaces (useful, for example, for joints other than ball-and-socket joints) may be used in embodiments of the present disclosure. Moreover, in some embodiments of the present disclosure that do use ball-and-socket joints, the bridge may comprise the socket(s), and the anchor(s) and/or adaptor(s) may comprise the ball(s).

Although the bridges <NUM> and <NUM> are described has being identical but for their different lengths, in some embodiments, two or more bridges used in a stabilization system according to embodiments of the present disclosure may comprise one or more differences. For example, the elongate member <NUM> of a shorter bridge <NUM> may have a smaller cross-sectional area than an elongate member <NUM> of a longer bridge <NUM>, because the same rigidity may be achieved with less structure to the shorter length of the bridge <NUM>. Additionally, the elongate members of different bridges may have different cross-sectional shapes; each bridge may comprise only one, or more than two, anchor interfaces; and each bridge may comprise two or more different kinds of anchor interfaces. Although the elongate members of the bridges described herein are all straight, in some embodiments the elongate members may be curved or otherwise non-linearly shaped.

In some embodiments, some or all of the bridges <NUM> or <NUM> may be manufactured of photoelastic material, from which a strain imposed on the bridge <NUM> or <NUM> or portion thereof may be determined by illuminating the photoelastic material with a particular light. In such embodiments, a sensor <NUM> as described above may be configured to illuminate the photoelastic material with the light in question and to detect a color, a reflective frequency, and/or another characteristic of the photoelastic material when so illuminated. A processor such as the processor <NUM> described above may then be used to calculate a strain imposed on the bridge <NUM> or <NUM>, which strain may then be displayed to a surgeon or other user, or used for one or more calculations regarding a needed surgical procedure or step thereof, or used to make one or more recommendations to the surgeon or other user, whether regarding the spinal stabilization system that comprises the bridge, or regarding a surgical plan, or otherwise regarding the patient.

Stabilization systems according to embodiments of the present disclosure may comprise a plurality of anchors such as the anchors <NUM> and/or <NUM>, a plurality of bridges such as the bridges <NUM>, <NUM>, and/or <NUM>, and in some embodiments one or more adaptors <NUM>. In use, an anchor such as the anchor <NUM> or <NUM> may be affixed to one or more anatomical features (e.g. one or more vertebrae, or more specifically the spinous process of one or more vertebrae), using the clamp formed by the arms <NUM> and <NUM> or <NUM> and <NUM> thereof. One or more bridges, as appropriate, may then be connected to the anchors (e.g., by inserting the anchor interface(s) of each bridge into the bridge interface(s) of each anchor, and/or vice versa). Once the system is generally positioned relatively to the corresponding anatomical features, the anchors may be locked in place by tightening the locking screw thereof, thus forcing the contact surfaces of the anchors closer to each other, increasing a clamping or squeezing force on the anatomical feature, and improving the engagement of the teeth of the anchors with the anatomical feature. Additionally, the bridges may be locked into place by tightening the set screws or other locking features of the bridge receptacles of the anchors. With the anchors and bridges locked into place, relative movement of the anatomical features to which the anchors are secured will be partially if not entirely prevented.

The use of anchors <NUM> and <NUM> having different heights, and of bridges <NUM>, <NUM>, and/or <NUM> having different lengths, beneficially enables a surgeon or other user of a stabilization system as described herein to select and use components that match the elevations and distances of the particular anatomical features of a given patient. A pediatric patient, for example, may require shorter bridges such as the bridge <NUM>, while an adult patient may require longer bridges such as the bridge <NUM>. Moreover, longer or shorter bridges may be required depending on the distance between anatomical features to which the anchors of the stabilization system are secured.

In some embodiments, one or more anchors such as the anchors <NUM> and <NUM> of a stabilization system may be secured to one or more anatomical features, without the use of any bridges. In such embodiments, the purpose of the anchors may not be to prevent motion of the anatomical feature(s) to which they are connected, but rather to enable detection of such motion. In such embodiments, an initial position of each anchor (once each anchor is connected to one or more anatomical features) may be determined based on detection of a tracking marker (e.g., a tracking marker <NUM> or <NUM> thereof). Subsequent positions of each anchor may then be determined in a similar manner, and compared to a previously determined position of each anchor to determine a movement of each anchor during the intervening time period.

Turning now to <FIG>, a method <NUM>,not part of the claimed invention, may be used to determine movement of one or more anatomical features and/or to determine a strain in a stabilization system as described herein. The method <NUM> may beneficially enable a surgeon to determine whether a registration is still valid; and/or to update a registration, an anatomical model, or a surgical plan; and/or to identify and remediate a potential negative impact to patient safety. The method <NUM> may be executed by a processor, for example a processor <NUM>, and may utilize one or more components of a system such as the system <NUM>.

The method <NUM> comprises receiving first sensor information corresponding to a first pose of an anchor at a first time (step <NUM>). The first sensor information may be received, for example, from a sensor <NUM> or from a navigation system <NUM>. The first sensor information may be or comprise information about a detected tracking marker (such as a tracking marker <NUM> or <NUM>) of an anchor (such as an anchor <NUM> or <NUM>). The first sensor information may be raw or processed data. In some embodiments, the first sensor information may be information input into a tracking marker detection algorithm (so as to detect a tracking marker, and based upon which a pose of the anchor may be determined), or information output by a tracking marker detection algorithm (comprising a determined pose of the tracking marker and thus of the anchor). The first sensor information may comprise sufficient information from which to determine a pose of the anchor, although in some embodiments additional information (such as, for example, information about a position of a tracking marker relative to an anchor on which the tracking marker is positioned) may be needed to determine a pose of the anchor.

The first sensor information may be received directly from a sensor <NUM> or a navigation system <NUM>, or may be received from or via a database <NUM>, a network such as the cloud <NUM>, or any other component or system. The first sensor information may, in some embodiments, comprise information obtained from one or more sensors as well as additional information obtained or received from, for example, a memory such as the memory <NUM>, or a database such as the database <NUM>.

The first time may be a time at which some or all of the first sensor information is obtained. The first time may also be or correspond to a time at which one or more registration images are obtained, such that the first pose of the anchor corresponds to a position of the anchor during a registration procedure.

The method <NUM> also comprises receiving second sensor information corresponding to a second pose of an anchor at a second time (step <NUM>). The step <NUM> may be substantially the same as the step <NUM>, but for the second time being after the first time. The second pose may be the same as the first pose or different than the first pose.

The method <NUM> also comprises determining an initial pose of an anatomical element (step <NUM>). The anatomical element is an anatomical element to which the anchor is secured. In some embodiments, the determining may comprise determining an initial pose of the anchor based on the first sensor information, based upon which determined initial pose of the anchor an initial pose of the anatomical feature may be determined. In such embodiments, additional information may be obtained and utilized in the determination (including, for example, information about a relative position of the anchor to the anatomical feature, which may be obtained from a surgical plan, or from a memory such as the memory <NUM>, or from a database such as the database <NUM>). In other embodiments, the first sensor information may comprise an initial pose of the anchor, and the initial pose of the anatomical feature may be determined based upon the first sensor information without first calculating or otherwise determining an initial pose of the anchor. In still other embodiments, the initial pose of the anatomical feature may simply be determined to be or assigned to be the initial pose of the anchor. Thus, for example, in embodiments where the first time corresponds to a time at which a registration process was conducted or completed, and the purpose of the method <NUM> is to determine whether an anatomical feature has moved since the registration process, any movement of the anchor may be considered a proxy for any movement of the anatomical feature, such that the actual pose of the anatomical feature need not be determined, but the anatomical feature may nevertheless be assigned an initial pose to use for future comparisons and movement determinations. In such embodiments, for ease of calculation, the assigned initial pose may simply be the initial pose of the anchor.

The method <NUM> also comprises determining an updated pose of the anatomical element (step <NUM>). Determining the updated pose of the anatomical element may be completed in the same manner as, or in a substantially similar manner to, the determining the initial pose of the anatomical element in the step <NUM>, except that the determining the updated pose of the anatomical element is based on the second sensor information and/or the second pose of the anchor rather than the first sensor information and/or the first pose of the anchor.

The method <NUM> also comprises comparing the updated pose of the anatomical element to the initial pose of the anatomical element to identify any movement of the anatomical element (step <NUM>). The comparing may comprise utilizing one or more algorithms such as the algorithms <NUM>, including one or more image processing algorithms, feature recognition algorithms, or other algorithms. Where the first sensor information and the second sensor information comprise images or other image data, the images may be overlaid on one another such that common features are aligned with one another, and the initial and updated poses of the anatomical element (and/or of the anchors, as appropriate) may be examined to determine if they are the same. Alternatively, the comparing may comprise simply comparing one or more numbers or other parameters describing the initial pose to one or more numbers or other parameters describing the second pose, and evaluating whether the numbers are the same or different. Where the result of the comparison is a determination that the pose of the anatomical element has not changed, then no further action may be taken. Where the result of the comparison is a determination that the pose of the anatomical element has changed, then a recommendation may be made to a surgeon or other user (e.g., via a user interface such as the user interface <NUM>) that a registration process should be repeated, or a surgical model may be updated to reflect the new pose of the anatomical element, or any other appropriate step may be taken.

In some embodiments, the method <NUM> also comprises receiving strain information corresponding to detected strain in a bridge (e.g., a bridge connecting two anchors, or an anchor and an adaptor, as described herein) (step <NUM>). The strain information may be or comprise raw or processed data from a sensor such as the sensor <NUM> (which may be, for example, a polariscope) regarding a detected strain in the bridge. For example, where the bridge is made entirely or partially of photoelastic material, the strain information may comprise information about a birefringence of the photoelastic material, and/or about one or more other characteristics of the photoelastic material, from which a strain in the bridge may be calculated or otherwise determined.

The method <NUM> also comprises causing a strain value to be displayed on a user interface (step <NUM>). The strain value may be a value calculated using any known method based on the strain information received in the step <NUM>. In some embodiments, the strain value may be obtained directly from the strain information, without any need for further calculations. The user interface may be, for example, a user interface <NUM>. The strain value may be displayed on the user interface to enable a surgeon to monitor patient safety, to evaluate a planned step of a surgical procedure, to determine whether or how to proceed with a surgical procedure or a step thereof, or to accomplish any other purpose.

Claim 1:
A spinal stabilization system, comprising:
a plurality of anchors (<NUM>, <NUM>), each anchor (<NUM>, <NUM>) comprising:
a clamp comprising a body (<NUM>, <NUM>) with a head (<NUM>) and a first arm (<NUM>, <NUM>) and a second arm (<NUM>, <NUM>), which second arm (<NUM>, <NUM>) comprises an elongate lever (<NUM>) and a foot (<NUM>), wherein the clamp is configured to engage an anatomical element with a first contact surface (<NUM>) of the first arm (<NUM>) and a second contact surface (<NUM>) of the second arm (<NUM>), the clamp movable between a fully open position and a fully closed position;
a locking screw (<NUM>) configured to selectively prevent the clamp from being moved into the fully open position, wherein the locking screw (<NUM>) comprises a threaded shaft (<NUM>), wherein the threaded shaft (<NUM>) is adapted to be received by an internally threaded aperture (<NUM>) on the first arm (<NUM>, <NUM>); and
a bridge interface (<NUM>) in the head (<NUM>); and
at least one bridge (<NUM>, <NUM>, <NUM>) comprising a rigid member (<NUM>, <NUM>, <NUM>) having a first end and a second end opposite the first end, each of the first end and the second end comprising an anchor interface (<NUM>, <NUM>);
wherein the bridge interface (<NUM>) is configured to receive the anchor interface (<NUM>, <NUM>),
characterized in that
the locking screw (<NUM>) also comprises an engagement head (<NUM>), wherein the engagement head (<NUM>) is configured to press against a surface (<NUM>) of the second arm (<NUM>, <NUM>), so that the second arm (<NUM>, <NUM>) can be prevented from rotating,
the internally threaded aperture (<NUM>) of the first arm (<NUM>, <NUM>) is positioned between the first contact surface (<NUM>) of the first arm (<NUM>, <NUM>) and the head (<NUM>), and
the surface (<NUM>) of the second arm (<NUM>, <NUM>) is positioned between the second contact surface (<NUM>) of the second arm (<NUM>, <NUM>) and the head (<NUM>).