FIELD OF THE INVENTION

The invention relates to robotically controlled and coordinated surgical procedures, and to the calibration and sizing of tools for those procedures. In particular, the invention relates to robotic systems comprising multiple robotic elements, such as robotic arms, end effectors, surgical instruments, cameras, sensors, imaging/tracking devices, or other devices useful for robotic surgery. The invention also relates to robotic systems wherein the placement and movement of the robotic elements are controlled and coordinated by a single control unit, and wherein all of the robotic elements are based on a single rigid chassis that is mobile and portable and, thus, are robotically coordinated at a single origin point. Specifically, multiple robotic elements may be attached to, and controlled by a single control unit and may be used in a coordinated fashion to deploy and/or relate to surgical instruments, trackers, cameras, and other surgical tools as part of a robotic surgery procedure. More particularly, in the context of robotic spinal surgery, multiple end effectors and robotic tools may be deployed on multiple robotic arms and controlled by a single control unit and may be used in a centrally coordinated fashion to perform a robotic surgical procedure, with the relative movements of each robotic element being coordinated by the central control unit. While the robotic system is capable of using many tools and end effectors, they may be supplied by many different manufacturers and may have different characteristics, creating a challenge for calibration with the robotic system. Most particularly, in the context of robotic surgery, random tools and end effectors supplied by multiple manufacturers may be calibrated according to their sizes, forms and special characteristic and used with a single robotic system according to the apparatus and methods provided by the present invention.

BACKGROUND OF THE INVENTION

Robotic surgery is well known in the art, as is the application of robotic techniques to spinal surgery procedures. Many robotic surgery systems, such as the da Vinci robotic surgery system from Intuitive Surgical, are teleoperated. Multi-arm robotic surgical systems are available in the field, for example those provided by Cambridge Medical Robotics, but these known systems are often also teleoperated and are all comprised of single arms deployed separately on separate carts or chassis with some level of coordination provided by a remotely- positioned control unit. Systems comprising multiple arms on multiple carts have significant drawbacks regarding integration into surgical workflow, along with an undesirably large footprint in the operating room. Also, the control of teleoperated units by a remotely-positioned control unit does not provide the level of control required for a full range of surgical procedures, particularly in the case of spinal surgery. With regards to robotic surgery (and non-teleported arms controlled by a human operator), accuracy will inevitably be superior in a system where all robotic arms are fixed to, and coordinated by, a single chassis comprising a single control unit.

A typical robotic surgical procedure may require the maneuvering of one or more end effectors deployed by robotic arms, the deployment of other instruments, placement of multiple passive or active markers on bone and/or on soft tissue, and one or more robotically controlled and maneuvered cameras/sensors that can be placed at varying distances and angulations from the surgical field, and one or more end effectors deployed by robotic arms. This dynamic is complicated by the presence of numerous surgical tools and implants on the market made by multiple manufacturers, which are not familiar to the robotic system provider, particularly in the spinal surgery market. Such a surgical robotic system which has the capability to calibrate and work with multiple unknown tools will have significant value and will enable health providers to widen their options and to provide better and more diverse treatment.

Such a multi-arm/multi-camera system mounted on, and controlled by, one cart, is not available in the current state of the art. There is a strong and long-felt need for such a system as it will enable the performance of a full range of spinal surgery procedures with robotically coordinated control and navigation at a level of accuracy not currently possible, while being agnostic to the brand or manufacturer of the surgical tools being used.

It is well understood in the areas of robotic surgery generally and spinal robotic surgery specifically that there are numerous manufacturers of tools and implants to be used in various surgical procedures. It is also the case that there are many companies that design and manufacture robotic systems to be used in surgical procedures, such as those mentioned already herein. This creates a mismatch and/or a lack of synchronization between robotic systems and robotic tool sets. A robotic device and its specific software may not optimally fit with the tool set of a particular manufacturer that has designed tools for particular types of surgical procedures, such as spinal surgical procedures, robotic or non-robotic. This mismatch can be true for all types of tools and accessories.

In this situation the robotic device and the robotic software of a company that develops a generic surgical robotic system, does not optimally fit any random implant and tool system that a certain hospital or surgeon might use. Moreover, there are dozens of implant systems in the market which continuously evolve and change, so for the robotic companies it is practically impossible to adapt their robotic systems to the huge number of tool variations in the marketplace. Additionally, the health regulatory agencies will usually force a certain kind of agreement between the robotic system’s manufacturer and the tool’s manufacturer in order to approve the use of the tools with the robot, which will complicate things significantly and eventually will delay advanced treatment to patients.

All of these barriers bring robotic companies to the situation in which they must be forced to form some kind of business relationship with one specific implant/tool company or to just settle on generic tool guidance for their robotic system. This creates a situation where the robot is designed without optimal fit to the full range of implants or tools that may be used with their robotic system (i.e., the surgeon can use the robotic system only for guidance and tool positioning, or at the top to drill a hole, but not to guide the tap or the screwdriver and implant). All of this of course results in less precise procedures that do not take advantage of the full capabilities of the robotic system and/or the full universe of tools that are available on the market, and thus does not benefit the patient or the surgeon.

There is thus a strong need for a robotic system that is capable of sizing and calibrating an unlimited range of tools and implants for robotic surgery, and for spinal surgery in particular Such a system is provided in the context of the present invention. Furthermore, the capabilities of such a system are greatly enhanced by the provision of a centrally controlled robotic system with multiple arms based on a single rigid chassis that is mobile and portable. Such a system can be selectively brought to the surgical field and can deploy tools and tool calibration apparatuses with its multiple, coordinated robotic arms.

SUMMARY OF THE INVENTION

Provided herein is a robotically controlled surgical system. Specifically, the inventive system is a centrally coordinated and synchronized robotic system for spinal surgery applications that allows for the precise sizing, positioning and calibration of robotic tools and implants. The robotic system is mobile and portable. The system comprises multiple robotic arms that each can hold at least one end effector, camera or navigation element for use in a spinal surgery procedure. The end effectors may include drilling tools or tool positioning elements. The cameras and navigation elements are for providing guidance for the movement of the robotic arms and deployment of the end effectors and tools. Multiple cameras and navigation elements may be used to provide a diversity of navigation information. The robotic arms of the inventive system, while mounted on a single chassis, have first joints that are spaced further apart than on multi-arm systems such as the da Vinci by Intuitive. Spaced apart robotic arms provide for greater reachability and maneuverability and for the application of greater force and leverage to various surgical tasks, among other advantages.

The synchronized movement of the robotic arms may be augmented by the interaction of the navigation cameras/sensors with active or passive markers that may be placed at the beginning or during the procedure. The movement of the robotic arms is synchronized by a central control unit from a single base that knows where the arms are based upon prior calibration of all arms. This robotic synchronization may be augmented by navigation cameras and markers. The single base can take the form of a rigid chassis that may optionally enclose the robotic arms in a retracted configuration. The base is portable and can be moved in and out of the surgical field by, for example, being positioned under the surgical table and then being removed at the end or during the procedure

Central to the inventive concept is a system and method for a synchronized and coordinated robotic system that can be adapted to work with any tool or implant system. At the core of the inventive concept is a mobile robotic system with multiple robotic arms that are synchronized with each other and share the same rigid base or chassis.

In a surgical robotic procedure, such as a spinal surgery robotic procedure, the various robotic arms are synchronized with the bony anatomy through the use of appropriate imaging modalities (e.g., X-ray, CT, MRI etc.) and the use of markers as described herein that may be placed on the bony anatomy, on the soft tissue, or on the robotic arms or robotic tools themselves. The synchronized and coordinated robotic arms may then be used for the sizing and calibration of robotic tools or implants to be used in the surgical procedure according to the following details.

In a representative embodiment of the present invention, the robotic system has at least two synchronized and coordinated robotic arms that are based in a common rigid chassis that is portable and that may be positioned under the surgical table for use during the surgical procedure. The movement of the robotic arms is coordinated by a central control unit that is located within the rigid chassis. The central control unit is able to gather navigation information provided by one or more cameras and by optionally placed markers on the soft tissue and/or bony anatomy of a patient. In this representative embodiment, one robotic arm holds a navigation camera/sensor that is able to track the patient with reference to the markers or other objects in the relevant space. A second robotic arm may hold a purpose-built calibration tool that has a set of dimensions that are known to the software of the robotic system. This calibration tool may also be part of the second robotic arm, but more flexibility may be provided by configuring the calibration tool to be detachable from the second robotic arm. In another embodiment, this calibration tool may be hand-held, thus two robotic arms may suffice for this purpose. A third robotic arm may then hold an end effector that can be configured to be adjustable, robotically or manually, and hold a large variety of surgical tool diameters, thus allowing the robotic system to accommodate the full range of diameters of robotic tools that can be found on the surgical market.

The tool can be placed inside this end effector manually by a surgeon or can be automatically robotically gripped by the robotic arms themselves. Once the tool is placed in the end effector, it can be brought in contact with the calibration device that is held by the second robotic arm or hand-held by the user. Held in this configuration, the tool can also be imaged and/or scanned by the navigation camera held by the first robotic arm and/or by another imaging device that is present in the operating room The first robotic arm holding the camera/sensor can now scan the tool and take multiple images of it from various positions (which are known to the central control unit). In this regard, several attributes of the robotic tool can be known, such as its diameter, its length and its three-dimensional model. These attributes can be provided to the central control unit of the robotic system and, taken together with the robotic system knowing the position of its robotic arms due to the imaging and sensing information provided by the cameras and sensors, the tool of known dimensions can be placed anywhere in the three-dimensional space of the surgical field that is in the view of the robotic system. The tool is thus calibrated, regardless of its manufacturer or precise design, allowing for the use of a very wide range of tools with a single robotic system. This genericizes the robotic system in terms of its tool compatibility, making it much more compelling to the surgeon as it allows for the use of tools that are precisely suited to the particular patient and surgical procedure. In this regard, the surgeon can choose what is best for the patient/procedure, rather than being limited by compatibility of a particular suite of tools or implants with the particular surgical robot being used at their hospital.

The sizing and calibration of tools and implants by two or three robotically coordinated arms is done intraoperatively and in sterile environment. As explained before there are in the market numerous implants and tools sets but few of them can be used in every surgery (sometimes without prior planning due to unforeseen changing surgical requirements). Also, specifically in spine surgery, every tool set, contain large number of different tools (screwdrivers, taps etc.), all sterile and ready for surgery. Many times, these tools are being assembled by the nurse/doctor only intraoperatively when sterile together from several different components together with the implant to a complex mechanism. Meaning- it is impossible to size and/or calibrate them while being fully assembled before the surgery when non-sterile. This robotic system and calibration method allows for tool sizing and calibration for any random tool with or without the implant attached to it while being sterile during the surgery under sterile conditions without adding time or discomfort to the surgical staff. The current inventive approach is differentiated from other known solutions primarily because it can calibrate and size any surgical tool, such as a screwdriver and implant to be used in spinal surgery, prior but most importantly during the surgical procedure. This accommodates the widest possible ranges of surgical procedures since it allows for the calibration and sizing to be done intraoperatively. Thus, even if the surgical approach and tool set changes during the surgery, a new tool set can be calibrated and sized and introduced seamlessly into the surgical workflow. In previously known approaches, tool sets can only be sized and calibrated by way of tool manufacturers placing proprietary navigation markers on the tools that are then recognizable by the robotic system that the tool set is designed to be used with. Thus, the use of the full range of tool sets with a generic robotic system is effectively impossible according to the current state of the art. The current inventor have solved this problem by providing the current system for calibrating and sizing any tool set without the need for proprietary navigation markers.

All of these needs and elements benefit tremendously from the central coordination and synchronized control of the inventive single-cart, multi-arm, non-teleoperated robotic system. Based on the placement of appropriately sized markers and the placement of navigation cameras at an appropriate distance and orientation to the target anatomy and the markers, movement of the robotic arms carrying end effectors, cameras and tools can be coordinated to provide for a safe and precise robotic spinal surgical procedure.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows a robotic tool calibration apparatus according to an embodiment of the present invention

Figure 2 shows three cut away view of various elements of a robotic tool calibration apparatus according to an embodiment of the present invention, including a tool calibration element, a tool holding element, and a robotic navigation camera. DETAILED DESCRIPTION OF THE INVENTION

With reference now to the figures and several representative embodiments of the invention, the following detailed description is provided.

In one embodiment of the invention shown in Figure 1, a robotic surgical system is shown. As shown in Figure 1, the robotic surgical system may be used for robotic spinal surgery. The robotic surgical system comprises a single rigid chassis 101. The chassis 101 is the base for three robotic arms 106, 107 and 108 that are placed relatively far apart on the chassis 101, typically approximately one meter apart, thus allowing for desirable attributes such as reachability, maneuverability and ability to apply significant force. The chassis 101 of the robotic surgical system may be placed under a surgical table 102. The robotic surgical system is portable and mobile and, thus, may be removably placed under the surgical table 102 before a surgical procedure and can later be moved away from the surgical field during the procedure or at its end. The robotic arms 106, 107 and 108 may optionally be configured to be able to retracted into the chassis 101 of the robotic surgical system such that the system can be moved into or out of the surgical field in a compact configuration.

In the embodiment of the present invention shown in Figure 1, a patient 103 is positioned on the surgical table 102. An element of the patient’s spinal bony anatomy of interest, in this case a vertebra 104, is shown. A marker 105 may optionally be placed on the vertebra 104 or on another portion of the patient’s bony anatomy or soft tissue.

Still with reference to Figure 1, robotic arm 106 may hold a navigation camera 112. Robotic arm 108 may hold a positioning element or end effector 109. The end effector 109 may optionally be configured to be attached to the robotic arm 108, but a detachable fitting of the end effector 109 is preferred. Robotic arm 107 may hold an end effector 110 that is optimally a device with an adjustable diameter, either robotically electro-mechanically or manually, e g , by the user pushing/rotating a button. A surgical tool 111 may then be placed in the end effector device 110 so that the tip of the tool 111 is positioned against the positioning element end effector 109. The end effector 110 may be interchangeable with iterations of variable diameter to hold tools 111 of different diameters. Alternatively, the end effector 110 may be a sleeve with a mechanism that can provide variable diameters depending on the tool 111 being used. In either embodiment, the desired configuration is for the tool 111 to be placed in the end effector 110 with a snug fit and for the tool 111 to progress through the end effector 110 until it reaches a stopping point known by the robotic system. In this regard, once the tool 111 is placed in the end effector 110 and reaches the known stopping point, a component of the position of the tool 111 in three-dimensional space is known to the robotic system. Once the tool 111 is placed in the end effector 110, the tip of the tool 111 can be positioned by the robotic arm 107, or manually by the surgeon, so as to make contact with the positioning element end effector 109. Adding a navigation marker to tool 111 will enable recognizing it by the navigation camera 112 even when it is hand-held by the user and not only robotically held. Contact between the tip of the tool 111 and the end effector 109 can also be achieved by the robotic arm 108 moving the end effector 109 into contact with the tip of the tool 111. In either method, synchronization is made possible by the robotic arms 107 and 108 being centrally controlled by the central control unit found in the single rigid chassis 101.

Once the tip of the tool 111 is positioned to touch the end effector 109, several attributes of the tool 111 can be measured. Since the end effector 110 has been chosen or adjusted to accommodate the diameter of the tool 111, the diameter of the tool is known. Since the tool 111 has been positioned in the end effector until it reaches a stopping point known to the robotic system, and since the position of the end effector 109 that is held by the robotic arm 108 or by the surgeon is known to the robotic system, and since the robotic arm 107 also has a position that is known to the robotic system, the length of the portion of the tool that will extend into the surgical field can be deduced. Furthermore, the navigation camera 112 can take single or multiple images of the tool 111, thus providing its three-dimensional model.

Once these attributes of the tool 111 are known by the robotic system, use of a tool 111 that the robot was “naive” to before the surgical procedure is possible and the robotic system can provide guidance for that tool 111 throughout the procedure. Accordingly, the robotic system can provide the position and progress of the tool 111 throughout the surgical procedure. For example, the robotic system can provide information about the progress of a drilling tool or the progress of a screwdriver advancing a screw into the patient’s bony anatomy. To facilitate this, the camera 112 is able to continuously take images of the surgical field and, knowing the diameter, length and three-dimensional model of the tool 111, the robotic system can determine its position and progress at all times.

Crucially, the various embodiments of the inventive system can determine the three key attributes of the tool set (length, diameter and 3D model) without the need for any navigation markers being placed on the tool set itself. This is only possible through the coordinated action of the robotic system’s three robotic arms that share a common base. Since the position and trajectory of each of the arms is known and coordinated by the central control unit, the key attributes of the tool set can be determined precisely and efficiently. This accommodates an unlimited universe of tool sets and more seamlessly accommodates a change in tool set during the surgical procedure. Similarly, this allows for the use of a generic robotic system according to an embodiment of the present invention with all available tool sets on the market. Conversely, in the current state of the art, the need for proprietary navigation markers on tool sets so that the robot can “see” the tool means that only a limited set of tools can be used with the particular robot. This limits surgical approaches and flexibility for the surgeon and may provide sub- optimal outcomes for the patient.

Figure 2 provides a close-up view of several components of the tool sizing and calibration capabilities of the present invention. Referring also back to Figure 1 for cross reference, robotic arm 106 holds a camera/sensor 212 that can be used to image the surgical field and determine the position and progress of a surgical tool 211. The surgical tool 211 has a certain diameter D and length L. The surgical tool is held by an end effector 210 that has an adjustable diameter that is adjusted to conform with the diameter d of the tool 211. The end effector is held by robotic arm 107. Robotic arm 108 holds an end effector 209 that can be positioned to contact the tip of the tool 211 or alternatively equipped with navigation markers and hand-held by the user. In an alternate top view, robotic arm 107 is shown with end effector 210 that has an adjustable diameter d that conforms to the diameter of the surgical tool 211. All of the embodiments shown in Figures 1 and 2 can be used in inventive methods of calibrating surgical tools or implants for carrying out spinal surgical procedures. In one such example, the robotic system shown in Figure 1 has three robotic arms 106, 107 and 108 that can be used to position a navigation camera 112, an end effector 109 and an end effector 110. A generic tool 111 may be chosen for its suitability for the particular surgical procedure. The tool 111 of known diameter d can be deployed into the end effector 110, the diameter of the end effector 110 can be adjusted to match the diameter d of the tool and the tool 111 will then stop its progress through end effector 110 at a stopping point known to the robotic system. Robotic arm 108 can then position end effector 109 at the tip of the tool 111, thus establishing the position of the tool 111 in three-dimensional space due to the fact that the position and movement of the robotic arms 106, 107 and 108 are known and controlled by the robotic system. Known position and sizing information can then be used to calculate the diameter, length and three-dimensional model of the tool 111 and the camera 112 can then be used to track the progress and position of the tool 111 during the surgical procedure. Use of the inventive system and method thus allows for the calibration and use of a wide variety of tools with a single robotic system, which in turn allows the surgeon to choose the best tool for the procedure, regardless of the manufacturer of the tool and regardless of whether commercial or regulatory arrangements are in place between the manufacturer of the surgical robot and the tool manufacturer.

One of skill in the art will realize that several variations on the disclosed embodiments are possible while staying within the bounds of the current invention. Solely by way of example, different variations in the number of navigation cameras, robotic arms, markers and end effectors can be used without departing from the invention. As another example, markers of varying sizes can be used and navigation cameras of various specifications can be used. As a further example, end effectors can be adjustable or interchangeable. The embodiments provided are representative in nature.