DEVICE FOR CONTROLLED ADJUSTMENT OF A SURGICAL POSITIONING UNIT

• US 20110218546A1
• Filed: 10/22/2009
• Published: 09/08/2011
• Est. Priority Date: 10/22/2008
• Status: Active Grant

• Current Assignee: Blue Ortho
• Original Assignee: Blue Ortho
• Inventors: Belei, Peter, De la Fuente Klein, Matias, Lavallee, Stephane, Boyer, Anthony, Radermacher, Klaus
• Granted Patent: US 8,974,460 B2
• Time in Patent Office: Days
• US Class Current: 606/104
• CPC Class Codes: A61B 17/155 Cutting femur
• CPC Class Codes: A61B 17/157 Cutting tibia
• CPC Class Codes: A61B 17/175 for preparing the femur for hip prosthesis insertion
• CPC Class Codes: A61B 17/1757 for the spine
• CPC Class Codes: A61B 17/7076 for driving, positioning or assembling spinal clamps or bone anchors specially adapted for spinal fixation
• CPC Class Codes: A61B 17/8615 at the central region of the screw head
• CPC Class Codes: A61B 17/8875 Screwdrivers, spanners or wrenches
• CPC Class Codes: A61B 2017/00482 with a code
• CPC Class Codes: A61B 2090/0811 for the position of a particular part of an instrument with respect to the rest of the instrument, e.g. position of the anvil of a stapling instrument
• CPC Class Codes: A61B 34/20 Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
• CPC Class Codes: A61B 90/98 using electromagnetic means, e.g. transponders

Abstract

The invention concerns a device for adjusting the position of a screw (13) that is able to move a part of a surgical instrument, said device (4) comprising: —a stem (41) comprising a tip (42) suited to the head (130) of the screw (13), —an actuated system (45) for driving said stem (41) in rotation, —communication means to communicate with a control unit (21), such that the control unit (21) transmits to the actuated system (45) the number of turns to apply to the stem (41) to reach the target position of the screw (13). The invention also concerns a surgical system for alignment of surgical guide means (14, 15), comprising: —a positioning unit comprising a fixed part (11) and a mobile part (12) supporting the surgical guide means (14, 15), the position of said mobile part (12) being adjustable with respect to the fixed part (11) by screws (13), —a referencing unit for detecting the position of the positioning unit with respect to a target position of the surgical guide means, —a control unit (21) for computing the target position of screws (13), —said device (4) for adjusting the positions of the screws (13).

Claims

1. A device for adjusting the position of a screw that is able to move a part of a surgical instrument, said device comprising:

a stem comprising a tip suited to the head of the screw,

a actuated system for driving said stem in rotation,

wherein said device further comprises communication means to communicate with a control unit, such that the control unit transmits to the actuated system a number of turns to apply to the stem to reach a target position of the screw.

2. The device of claim 1, wherein the control unit is included in a navigation system or is connected to a medical imaging system.

3. The device of claim 1, wherein said device further comprises detection means for identifying which screw the tip of the device is in contact with, wherein the communication means of the device is able to transmit said identification information to the control unit.

4. The device of claim 3, wherein said detection means comprises a sliding stem able to slide inside the stem and a position sensor adapted to measure displacement of the sliding stem with respect to the tip of the device.

5. The device of claim 3, wherein said detection means comprises electrical connectors arranged at the tip of the device and an ohmmeter.

6. The device of claim 3, wherein the detection means comprises a “

Hall effect”

sensor arranged in the tip of the device.

7. The device of claim 3, wherein said detection means comprises an optical sensor, a first optical fiber and a second optical fiber, the first and second optical fibers being arranged inside the stem so as to respectively light a cavity of a screw head and bring reflected light to said optical sensor.

8. The device of claim 3, wherein said detection means comprises a tracker rigidly attached to the device.

9. A surgical system for alignment of surgical guide means with respect to a solid, said system comprising:

a positioning unit comprising a fixed part that is fixed with respect to the solid and a mobile part supporting the surgical guide means, a position of said mobile part being adjustable with respect to the fixed part by one or more screws,

a referencing unit for detecting a position of the positioning unit with respect to a target position of the surgical guide means,

a control unit for computing a target position of said one or more screws, wherein said system further comprises the device of claim 1.

10. The surgical system of claim 9, wherein the surgical guide means comprises one or more drill guides or one or more cutting blocks.

11. The surgical system of claim 10, wherein the control unit is connected to an imaging system and the referencing unit comprises one or more calibration markers that are detectable by the imaging system.

12. The surgical system of claim 11, wherein the referencing unit is removably attached to an attachment unit rigidly fixed to the solid.

13. The surgical system of claim 10, wherein the control unit is included in a navigation system and the referencing unit comprises a first reference element attached to the solid or to the fixed part of the positioning unit, that generates a first three-dimensional reference tracker, which is independently registered in the navigation system and a second reference element applied to the mobile part of the positioning unit that needs to be adjusted, that generates a second three-dimensional reference tracker, which is independently registered in the navigation system.

14. The surgical system of claim 13, wherein the position of the mobile part of the positioning unit is adjusted to a target defined by use of the navigation system, and the control unit determines the number of turns of the one or more screws needed to reach the target.

15. The surgical system of claim 9, further comprising means for indicating to the user which screw should be turned and how many turns should be applied to each screw to reach the target

16. The surgical system of claim 15, further comprising a ruler on the positioning unit and/or on the adjustment device to adjust each screw.

17. The surgical system of claim 9, further comprising an attachment unit for attachment to the spine of a patient, a referencing unit attached to the attachment unit and a positioning unit attached to the attachment unit and/or to the referencing unit (34), the positioning unit comprising four screws for adjusting the position and/or orientation of a drill guide.

18. The surgical system of claim 9, further comprising an attachment unit for attachment to the femoral head of a patient, a referencing unit attached to the attachment unit and a positioning unit attached to the attachment unit and/or to the referencing unit, the positioning unit comprising four screws for adjusting the position and/or orientation of a drill guide.

19. The surgical system of claim 9, wherein the positioning unit comprises a fixed part for attachment to the tibia or to the femur of a patient, a mobile part supporting a cutting plane and three screws for adjusting the position of the cutting plane with respect to the fixed part.

20. The surgical system of claim 9, wherein the positioning unit is a spacer comprising two parallel plates and a screw for adjusting the distance between the plates.

21. A method for aligning a surgical guide comprising:

providing the surgical system of claim 9;

attaching the surgical positioning unit to a patient;

performing medical imaging, optionally by establishing one or more multiplanar X-ray images and/or by establishing of a volumetric data set, wherein at least parts of the referencing unit as well as of a bone of said patient are imaged;

transferring the imaging to a computer and determining a pose of the surgical guide means by an operator, a position of the referencing unit and a set of corresponding screw parameters for the positioning unit.