SURGICAL ROBOTIC SYSTEM

Abstract

A surgical robot system whose robotic arm is divided into two parts, and is connected to the patient at the junction of the two parts, by means of a bone connector. The section between the bone connector and the robotic base has a predetermined level of flexibility, enabling the bone connector limited movement. Consequently, the patient's body can also move without the bone connector exerting excess forces on the patient, and without detachment from the patient. The arm section between the bone connection link and the end actuator has high rigidity, such that the pose of the end actuator relative to the patient is accurately maintained. As the patient undergoes small movements, such as in breathing or coughing, the bone connector and base connection arm section, move together with motion of the patient's bone, while the pose of the end actuator relative to the patient is accurately maintained.

Claims

1. A robotic surgical system, comprising: a base for fixing said system relative to an operating table; an end actuator for enabling alignment of a surgical tool for performing a procedure on a subject on said operating table; a set of robotically actuated arms connected between said base and said end actuator, said set comprising: a first section connected at one end to said base, and a second section connected to said first section remotely from said end, and having said end actuator at its end region remote from its connection to said first section; and a connection element coupling a point between said first section and said second section to a part of said subject's anatomy, wherein the mechanical rigidity of said first section is configured to be less than that of said second section.

2. A robotic surgical system according to claim 1 wherein said mechanical rigidity of said first section arises at least in part from a predetermined rigidity of at least one link of said first section.

3. A robotic surgical system according to claim 1 wherein said mechanical rigidity of said first section arises at least in part from the stiffness of at least one joint of said first section.

4. A robotic surgical system according to claim 3 wherein the stiffness of at least one joint of said first section is adjustable by control of the gain of the electronic feedback controlling said joint.

5. A robotic surgical system according to claim 4 wherein the mechanical rigidity of said first section is adjusted electronically according to the expected motion of said part of said subject's anatomy.

6. A robotic surgical system according to claim 4 wherein the mechanical rigidity of said first section is adjusted electronically according to the pose of said first section.

7. A robotic surgical system according to any of the previous claims, wherein said connection element is connected to a junction region between said first section and said second section of said set of robotically actuated arms.

8. A robotic surgical system according to any of claims 1 to 6, wherein said connection element is connected to a component situated between said first section and said second section of said set of robotically actuated arms.

9. A robotic surgical system according to any of the previous claims, wherein said connection element is connected to a junction between said first section and said second section of said set of robotically actuated arms.

10. A robotic surgical system according to any of the previous claims, wherein said first section of said set of robotically actuated arms has at least one joint configured to have a reduced level of rigidity in comparison with the maximum rigidity attainable in such a type of joint, such that the mechanical rigidity of said first section is less than that of said second section.

11. A robotic surgical system according to claim 10, wherein said reduced level of rigidity of said joint is generated by reducing the gain of the control circuit associated with said joint.

12. A robotic surgical system according to any of the previous claims, wherein said first section of said set of robotically actuated arms has at least one arm member configured to have a reduced level of stiffness in comparison with the maximum stiffness attainable in such a type of arm member, such that the mechanical rigidity of said first section is less than that of said second section of said set of robotically actuated arms.

13. A robotic surgical system according to any of claims 1 to 9, wherein said second section of said set of robotically actuated arms has sufficient rigidity that the position of said end actuator relative to the location of said point coupled to said connection element is maintained within a level which is determined to achieve the required accuracy of said surgical procedure.

14. A robotic surgical system according to any of the previous claims, further comprising an optical scanning system for detection of the subject's body, and a control system inputting the position of said set of robotically actuated arms and of the position of said body in order to prevent collision of said set of robotically actuated arms with said body or with an implantation accessory.

15. A robotic surgical system according to claim 14, wherein said optical scanning system is located either on said set of robotically actuated arms, or an a static point in the vicinity.

16. A robotic surgical system according to any of the previous claims, wherein the mechanical rigidity of said first section is sufficiently less than that of said second section that said part of said subject's anatomy coupled to said connection element can move by up to the extent of the subject's estimated motion without becoming uncoupled from said connection element.

17. A robotic surgical system according to any of the previous claims, wherein said connection element is switchable between a rigid state and a released state allowing longitudinal extension of said connection element, said system further comprising a force sensor such that said connection element switches from its rigid state to its released state when said force along said connection element exceeds a predetermined level.

18. A robotic surgical system according to claim 17, wherein said mechanical rigidity of said first section compared to that of said second section is such that said part of said subject's anatomy coupled to said connection element can move by up to the estimated extent of the subject's motion before said connection element switches between its rigid state and its released state.

19. A robotic surgical system according to claim 17, wherein said predetermined level of said force is such that for a connection to the subject's sternum, said sternum can move by up to 12 mm before said predetermined level of force is reached.

20. A robotic surgical system according to any of claims 16, 18 and 19, wherein said part of said subject's anatomy coupled to said connection element can move with three directions of freedom.

21. A robotic surgical system according to claim 17, wherein said connection element is adapted to reconnect after release, at a known position.

22. A method of performing spinal surgery on a subject, comprising: laying said subject in a lateral position on an operating table; providing a robotic surgical system having an operating envelope that can enable a surgical tool to reach both the lateral side of the subject and the posterior spinal position; performing a robotic Lateral Interbody Fusion procedure on said subject laying in said lateral position; and directing said robotic surgical system to perform a percutaneous posterior spinal procedure, wherein both of said procedures are performed without the need to move said subject.

23. A method according to claim 22 wherein the lateral insertion of an intervertebral element and said percutaneous posterior spinal procedure are robotically performed using a single registration procedure.

24. A method according to claim 22 wherein said robotic surgical system is attached to an anatomy part of said subject without detachment between said procedures.

25. A method according to claim 22 wherein said operating envelope is obtained by use of a robotic surgical system according to any of claims 1 to 21.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which:

[0041] FIG. 1 is a schematic view of a floor mounted surgical robot system of the present disclosure; and

[0042] FIG. 2 to FIG. 4 are schematic isometric views of an alternative robotic surgical system in which the robotic base is connected by means of a support post to the operating table.

DETAILED DESCRIPTION

[0043] Reference is first made to FIG. 1, which is a schematic view of a floor mounted surgical robot system of the present disclosure, the patient 19 is shown lying on the operating table and is attached by means of a bone connection link 13 to an attachment location 18 of the robotic arm. The robotic arm of the system is shown made up of arm parts 17 connected by rotary or prismatic joints 16, and is divided into two parts. The arm section 11, known as the robotic base arm, situated between the bone connection link 13 and the robotic base 12, has a structure such that that section has a predetermined level of flexibility, enabling the bone connection link 13 to move to a limited extent. Consequently, the patient's body can also move to that extent, without exerting excess pressure on the patient, or without the patient becoming unattached from the bone connection link 13. In contrast to that section, the arm section 15 situated between the bone connection link 13 and the end actuator 14 of the robot, known herewithin as the robotic actuator arm, has a high level of rigidity such that the accuracy of the pose of the end actuator 14, relative to the patient's anatomy, is maintained at the highest possible level. Consequently, as the patient's body undergoes small movements, such as generated by breathing or coughing, the bone connection link 13 and the attachment location 18 move together with motion of the patient's bone, thereby accurately maintaining the pose of the end actuator 14 of the robot relative to the attachment location 18 and hence to the patient's body position as it moves. In FIG. 1, the end actuator 14 of the robot is shown as a guide tube holding a surgical tool, though this is understood to be only one example of the use of the end actuator, which could hold a drill, scalpel and any other surgical tool.

[0044] In FIG. 1, the robot base 12 is shown as a floor mounted base, but it is be understood that the robot base could be attached to a support post attached to the operating table, as shown in FIGS. 2 to 4 hereinbelow, or any other feature in the vicinity, such as the ceiling over the operating table. The base may even be supported on a cart. Although such a cart should be locked in position in order to ensure safe operation, the natural flexibility of a cart amounted robot, as compared with a bed or floor mounted robot, may contribute in part to the intentionally incorporated flexibility of the base system. In such a configuration, the true base may be considered to be the wheels of the cart locked on the floor of the Operating Room, while the cart itself may be considered to be part of the robotic base arm.

[0045] Additionally, even a support post or similar can have an intrinsic flexibility, such that it may also be considered to be part of the flexible mechanical path between the base and the bone connection link 13.

[0046] In the implementation shown in FIG. 1, the bone connection link can be either a static rod, or it can include an automated bone connection unit 10, as described in the above mentioned International Published Patent Application WO2015/087335.

[0047] A three dimensional X-ray target (not shown) can be held by the robotic actuator arm, such that a fluoroscopic X-ray image of the region of interest including the target, can be used for registration of the robotic frame of reference to any preoperative images used in planning the surgery.

[0048] Reference is now made to FIG. 2, which is a schematic isometric view of an alternative robotic surgical system in which the robotic base is connected by means of a support post 20 to the operating table 21. The robotic arm has two sections: [0049] (i) a robotic base arm section 22 comprising struts 23 and rotary and prismatic joints 24, whose flexibility, together with the bending of the support post 20, which should therefore also be considered part of the robotic base arm, provide the base arm section with the desired extent of flexibility, and [0050] (ii) a robotic actuator arm section 25, which is a very rigidly constructed section, made up in this exemplary system, of several rotary joints 26 and the end actuator 27 itself. If a larger robotic work envelope is desired, additional links may be incorporated between the rotary joints 26.

[0051] The bone connection link 28 is shown attached to its fixation location between the base arm section 22 and the robotic actuator arm section 25. At its distal end, there may be a bone connecting component, such as a clamp or a pointed or threaded end such as a k-wire. Additionally, the bone connection link 28 may incorporate an automated bone connection unit such as that shown in FIG. 1. The optical scanning head 29, which may be a small sensor device, is mounted in a position where it can scan the surface as the robot arm moves, such as at the end of the actuator arm 27. An optional navigation camera is shown mounted on the support post 20, in order to track items such as surgical tools, even if not involved in navigating them to their target. The robotic base may be connected to the bed through a mechanism that floats the robot base and arm so that the nurse can attach it easily to the bed.

[0052] Reference is now made to FIG. 3, which is an additional view of the system shown in FIG. 2, showing the parts described in FIG. 2 from an alternative vantage point. A display screen 30 is also shown for providing information to the surgeon performing the operation.

[0053] Reference is now made to FIG. 4, which is a further schematic drawing showing an operation in progress with the system control cart 40, and the surgeon 41 surveying the data on the operating table screen 30. The bone connection link 28 is shown attaching the junction of the base arm section and the robotic actuator arm section to a point in the lower spine of the patient.

[0054] It is appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described hereinabove. Rather the scope of the present invention includes both combinations and subcombinations of various features described hereinabove as well as variations and modifications thereto which would occur to a person of skill in the art upon reading the above description and which are not in the prior art.