METHOD AND ASSOCIATED INSTRUMENTATION FOR INSTALLATION OF SPINAL DYNAMIC STABILIZATION SYSTEM

• US 20080262551A1
• Filed: 04/19/2007
• Published: 10/23/2008
• Est. Priority Date: 04/19/2007
• Status: Active Grant

• Current Assignee: Zimmer Biomet Spine, Inc. (Zimvie Incorporated)
• Original Assignee: Zimmer Spine, Inc. (Zimmer Biomet Holdings, Inc.)
• Inventors: Hestad, Hugh D., Gisel, Thomas J., Kroll, Mark J., Rice, Mark W. Darst
• Granted Patent: US 7,922,725 B2
• Time in Patent Office: Days
• US Class Current: 606/268
• CPC Class Codes: A61B 17/56 Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor
• CPC Class Codes: A61B 17/7008 with parts of, or attached to, the longitudinal elements, bearing against an outside of the screw or hook heads, e.g. nuts on threaded rods A61B17/7007 takes precedence
• CPC Class Codes: A61B 17/7031 made wholly or partly of flexible material
• CPC Class Codes: A61B 17/7083 Tools for guidance or insertion of tethers, rod-to-anchor connectors, rod-to-rod connectors, or longitudinal elements
• CPC Class Codes: A61B 17/7085 for insertion of a longitudinal element down one or more hollow screw or hook extensions, i.e. at least a part of the element within an extension has a component of movement parallel to the extension's axis
• CPC Class Codes: A61B 17/88 Osteosynthesis instruments; Methods or means for implanting or extracting internal or external fixation devices A61B17/7074 takes precedence
• CPC Class Codes: A61B 17/8869 Tensioning devices
• CPC Class Codes: A61B 2017/564 Methods for bone or joint treatment

Abstract

In one embodiment, a spinal stabilization apparatus includes a vertebral anchor having a head portion and a bone attachment portion. An elongate, flexible guide is removably coupled to the head portion of the vertebral anchor and has a channel extending longitudinally thereof and communicating with a slot in the head portion of the anchor. An elongate cord may be received within the channel to facilitate inserting and securing a spacer between pairs of anchors installed into adjacent vertebrae of a person'"'"'s spine.

Claims

1. A method of installing a spinal stabilization construct comprising the steps of:

installing first and second vertebral anchors onto first and second vertebrae, respectively, each vertebral anchor having an upwardly open channel adapted to receive therein a flexible connecting element extending between the first and second vertebrae;

mounting first and second access members onto the first and second vertebral anchors, respectively, each access member having a cannula to provide access to the channel of the respective vertebral anchor;

inserting the connecting element through a slot in the first access member;

advancing the flexible connecting element from the slot in the first access member into the channel in the first vertebral anchor;

securing the flexible connecting element to the channel of the first vertebral anchor with a first fastener;

positioning a spacer on the connecting element adjacent the first vertebral anchor;

inserting the flexible connecting element through a slot in the second access member;

advancing the flexible connecting element from the slot in the second access member into the channel in the second vertebral anchor;

positioning the spacer between the vertebral anchors; and

securing the flexible connecting element to the channel of the second vertebral anchor with a second fastener.

2. The method of claim 1 further comprising:

tensioning the connecting element after the first securing step and prior to the second securing step.

3. The method of claim 1 further comprising:

distracting the first and second vertebrae during placement of the spacer.

4. The method of claim 2 wherein the second advancing step and the distracting step are performed generally simultaneously.

5. The method of claim 1 wherein the securing steps each further comprise:

passing the respective fastener through the respective access member percutaneously to the respective channel.

6. The method of claim 1 wherein the steps are performed generally sequentially in the order recited in claim 1.

7. The method of claim 1 wherein each vertebral anchor is a pedicle screw having a threaded shaft and a head, the channel being formed in the head, the installing step further comprising:

coupling a tool to the head of each of the pedicle screws; and

screwing the shaft of each of the pedicle screws into the associated vertebrae.

8. The method of claim 6 wherein the tool has a tubular member with a cannula extending there through, the coupling step further comprising:

inserting the respective access member mounted on the associated pedicle screw into the cannula of the tool.

9. The method of claim 6 wherein the tool is utilized in the first advancing step.

10. The method of claim 1 further comprising:

trimming the flexible connecting element to length; and

removing the access member from the vertebral anchors.

11. The method of claim 2 wherein the second advancing step and the distracting step are performed with a tool having a tubular member with a cannula extending there through and a distal end, the method further comprising:

inserting the cannula of the tool over the second access member mounted on the second vertebral anchor; and

contacting at least one of the spacer and the flexible connecting element with the distal end of the tool.

12. The method of claim 10 further comprising:

cradling the spacer with an arcuate flange on the distal end of the tool.

13. A system for stabilizing a patient'"'"'s spine comprising:

first and second vertebral anchors adapted to be anchored to first and second vertebrae, respectively, each vertebral anchor having an upwardly open channel;

a flexible connecting element adapted to be extend between the vertebral anchors and be seated in the channels;

a spacer adapted to be positioned between the channels of the vertebral anchors with the connecting element passing there through;

first and second fasteners adapted to be mated with the channels of the first and second vertebral anchors, respectively, to secure the flexible connecting element thereto;

first and second access members adapted to be mounted on the first and second vertebral anchors, respectively, each access member having a cannula to provide access to the vertebral anchor when mounted thereon;

a slot in each of the access members in communication with the associated channel when mounted on the vertebral anchor; and

a first tool having a tubular member with a cannula extending there through and configured to fit over one of the access members when mounted on the associated vertebral anchor, the first tool being adapted to advance the flexible connecting member along the slot and into the channel of one of the vertebral anchors and to position the spacer between the vertebral anchors.

14. The system of claim 13 further comprising:

an arcuate flange on a distal end of the first tool adapted to cradle the spacer for distraction between the vertebral anchors.

15. The system of claim 13 wherein the flexible connecting element is a flexible cord adapted to be tensioned between the vertebral anchors.

16. The system of claim 13 wherein each fastener is a set screw adapted to be threadably mated with the vertebral anchor.

17. The system of claim 13 further comprising:

a handle on the proximal end of the first tool adapted to be grasped by a surgeon for manipulation of the first tool.

18. The system of claim 13 further comprising:

a second tool having a tubular member with a cannula extending there through and configured to fit over one of the access members when mounted on the associated vertebral anchor, the second tool being adapted to advance the flexible connecting member along the slot and into the channel of one of the vertebral anchors.

19. The system of claim 18 further comprising:

a handle on the proximal end of the second tool adapted to be grasped by a surgeon for manipulation of the second tool.

20. The system of claim 19 further comprising:

complementary mating features proximate the distal end of the second tool and at least one of the vertebral anchors and the access members to thereby couple the second tool thereto.

21. The system of claim 20 wherein each vertebral anchor is a pedicle screw having a threaded shaft and a head, the channel being formed in the head, the second tool being adapted to screw the threaded shaft into the vertebrae upon rotation of the second tool when mated with the pedicle screw.

22. The system of claim 21 wherein the complementary mating features further comprise:

a first recess on the distal end of the second tool;

a second recess on the head of the pedicle screw;

a first, outwardly directed, protrusion proximate a distal end of the access member; and

a second, inwardly directed, protrusion proximate the distal end of the access member;

wherein the first and second recesses are configured to mate with the first and second protrusions, respectively.

23. The system of claim 13 wherein each access member further comprises:

a sleeve with a pair of longitudinal diametrically opposed slots.

24. A system for stabilizing a patient'"'"'s spine comprising:

first and second pedicle screws each having a threaded shaft and a head with an upwardly open channel, the first and second pedicle screws adapted to be anchored to first and second vertebrae, respectively;

a flexible member adapted to extend between the pedicle screws and be seated in the channels;

a spacer adapted to be positioned between the heads of the pedicle screws with the cord passing there through;

first and second set screws adapted to be mated with the channels of the first and second pedicle screws, respectively, to secure the cord thereto;

first and second sleeves adapted to be mounted on the first and second pedicle screws, respectively, each sleeve having a cannula to provide access to the pedicle screw when mounted thereon;

a longitudinal slot in each of the sleeves in communication with the associated channel when mounted on the pedicle screw;

a first tool having a tubular member with a cannula extending there through and configured to fit over one of the sleeves when mounted on the associated pedicle screw, the first tool being adapted to advance the flexible member along the slot and into the channel of one of the pedicle screws and to position the spacer between the pedicle screws;

a second tool having a tubular member with a cannula extending there through and configured to fit over one of the sleeves when mounted on the associated pedicle screw, the second tool being adapted to advance the flexible member along the slot and into the channel of one of the pedicle screws; and

complementary mating features proximate the distal end of the second tool and at least one of the pedicle screws and the sleeves to thereby couple the second tool thereto, the second tool being adapted to screw the threaded shaft into the vertebrae upon rotation of the second tool when mated with the pedicle screw.

25. The system of claim 24 further comprising:

an arcuate flange on a distal end of the first tool adapted to cradle the spacer for distraction between the vertebral anchors.

26. The system of claim 24 wherein the complementary mating features further comprise:

a first recess on the distal end of the second tool;

a second recess on the head of the pedicle screw;

a first, outwardly directed, protrusion proximate a distal end of the sleeve; and

a second, inwardly directed, protrusion proximate the distal end of the sleeve;

wherein the first and second recesses are configured to mate with the first and second protrusions, respectively.