Intraoperative fluoroscopic registration of vertebral bodies

Abstract

A method for the fluoroscopic registration in real time for placement of pedicle screws or the like during spinal surgery, comprising creating a lateral image in which a pedicle has appropriate anatomic contour and superior endplate, advancing a pin into the pedicle starting in the posterior cortex and moved far enough into the pedicle to anchor the pin, rotating the fluoroscopy to obtain an AP image of the pedicle which is moved to render the pin to be neutral in a cephalad to candad direction, and positioning a pedicle screw in the pedicle following 2D contour mapping generated by manual or automated templating.

Claims

1. A method for enhancement of fluoroscopic registration in real time for placement of pedicle screws, vertebral augmentation or interbody spacers/artificial discs during spine surgery, comprising: creating, by an imaging device in a first position for lateral imaging, a lateral image of a vertebral body in which a superior endplate is at least partially visualized, in accordance with the created lateral image, advancing a pin into the vertebral body starting in the posterior cortex and moved far enough into the vertebral body until bony purchase is obtained so that the pin is anchored, rotating the imaging device from the first position to a second position for Anterior-Posterior (AP) imaging to obtain an AP image of a pedicle, wherein the obtained AP image renders the pin positioned in the lateral image to be neutral in a cephalad to caudad direction, and positioning a pedicle screw, vertebral augmentation, interbody spacer, or artificial disc in or adjacent to the pedicle following a 2D contour mapping generated by manual templating or automated templating.

2. The method of claim 1 wherein the pin is smooth or threaded.

3. The method of claim 1 wherein the pin is advanced by a drill.

4. The method of claim 1 wherein a targeting device comprising a housing is connected to multiple pins including the pin advanced into the vertebral body to provide for the placement of an awl into the pedicles for screw, cement or interbody device placement.

5. The method of claim 4 wherein the targeting device is adapted to be placed on a patient's skin for minimally invasive surgery or open surgery placement.

6. The method of claim 5 wherein the multiple pins are movably mounted within pin guides that are slidably mounted on a track of the targeting device.

7. The method of claim 6 wherein the track is curved so that the position and angle of the multiple pins can be adjusted.

8. The method of claim 7 wherein the multiple pins and the pin guides are operatively connected to one or more angled guide devices for moving them to desired positions on a patient.

9. The method of claim 7 wherein the housing of the targeting device is radiolucent.

10. The method of claim 4 wherein the awl is provided with a goniometer.

11. The method of claim 4 wherein the awl is attached to a C-arm housing and removably detachable.

12. The method of claim 1 wherein a targeting device comprising a housing is connected to multiple pins including the pin advanced into the vertebral body to provide for the placement of a cannula into the pedicles for screw, cement or interbody device placement.

13. The method of claim 1, wherein the obtained AP image matches a 2D contour mapping generated by manual templating or automated templating.

14. The method of claim 1, wherein a targeting device is connected to multiple pins including the pin advanced into the vertebral body, the targeting device comprises a housing, the housing comprises a track within which multiple pin guides for mounting the multiple pins are mounted, and the track is curved so that the position and angle of the multiple pins can be adjusted.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a lateral computer image of a bony spine in which one or more pins are inserted using lateral fluoroscopy into the posterior cortex of a vertebral body and/or pedicles starting in the posterior cortex;

(2) FIG. 2 is a computer image in which the fluoroscopy or similar imaging of FIG. 1 is rotated to obtain an AP image for each vertebral body and angled, rotated or moved to obtain an image which renders the pins placed in lateral imaging to be neutral in a cephalad to caudad direction and congruent with 2D contour mapping generated by a method disclosed, for example, in U.S. Pat. No. 7,235,076;

(3) FIG. 3 is a computer image of a pin inserted in a posterior cortex in the lateral sagittal view of FIG. 1;

(4) FIG. 4 is a computer image of a pin inserted in a pedicle in the AP coronal view of FIG. 2;

(5) FIG. 5 is a side elevational view of an awl attached to a C-arm housing;

(6) FIG. 6 is a bottom plan view of the awl shown in FIG. 5;

(7) FIG. 7 is a coronal view of a vertebral body showing an awl not zeroed out and an adjacent pin, and an awl zeroed out;

(8) FIG. 8a is a perspective view of an awl with a built in goniometer to obtain coronal, sagittal and transverse registration using a digital or visual output display;

(9) FIG. 8b is a perspective view of a display for the awl shown in FIG. 8a;

(10) FIG. 9 is a perspective of a targeting device mounted on a patient's back for guiding pins to be positioned in the spine;

(11) FIG. 10 is a partial side elevational view of the targeting device shown in FIG. 9; and

(12) FIG. 11 is a partial perspective view of the adjusting mechanism of the targeting device.

DETAILED DESCRIPTION OF THE INVENTION

(13) To enhance the fluoroscopic registration in real time for placement of pedicle screws, vertebral augmentation or interbody spacers/artificial discs during spine surgery, a lateral image is taken by a computer or other device in which the pedicle P has appropriate anatronic contour and superior end plate is adequately visualized. Once this image is obtained, a pin 10, smooth or threaded, formed of any suitable material is advanced with a drill or other device starting in the posterior cortex and advanced far enough into the vertebral body B until adequate bony purchase is obtained to hold it firmly anchored, as shown in FIGS. 1 and 3. This is particularly effective for positioning pedicle screws or other devices in regions with significant deformity or in the lumbosacral junction to identify the sacrum.

(14) Once this is achieved, the fluoroscopy or similar imaging is rotated to obtain an AP image for each individual vertebral body B and angled, rotated or moved to obtain an AP image which renders the pin 10 placed in lateral imaging to be neutral in a cephalad to caudad direction, as shown in FIGS. 2 and 4. Placement of pedicle screws, vertebral augmentation or interbody spacers/artificial discs in or adjacent to the pedicle then follows the 2d contour mapping generated by manual templating or integrated with automated templating generated by appropriate software. The pin or pins 10 facilitate the placement of pedicle screws or other devices.

(15) FIGS. 5 and 6 illustrate an awl A which is constructed to be attached to a C-arm housing 12 that enables the coupling of the awl A to a C-arm. The awl A is provided with a handle 14 and a tip 16.

(16) FIG. 7 illustrates manual registration of an awl A with a C-arm to obtain zero degree coordinates after vertebral body B registration and a laterally placed pin 10. The awl A.sub.1 is not zeroed out and is adjacent to the pin 10. The awl A.sub.2 is zeroed out.

(17) FIGS. 8a and 8b illustrate an awl A with a built in goniometer 18 to obtain coronal, sagittal and transverse registration with appropriate software using digital or visual output display.

(18) A targeting device is illustrated in FIGS. 9-11 wherein, by utilizing pins 10 placed into the spine S, the targeting device T can be connected to them such that it allows for placement of, for example, cannula, and different types of awls to advance into the pedicle for screw, cement or assisting with interbody placement. The targeting device can be placed on a patients' skin for minimally invasive surgery or open surgery placement.

(19) The targeting device comprises a housing 20 that may be radiolucent and is provided with spaced rails 22 defining a track 24 in which pin guides 26 are slidably mounted on ball bearings 28 or the like. Pins 10 are slidably mounted in the guides 26 and one or more angled guide devices 30 are operatively connected to the guides 26 and pins 10 to move them to desired positions on the patient.

(20) While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.