Surgical access system and related methods

• US 8,172,750 B2
• Filed: 03/17/2010
• Issued: 05/08/2012
• Est. Priority Date: 01/16/2003
• Status: Active Grant

• Current Assignee: Nuvasive Incorporated
• Original Assignee: Nuvasive Incorporated
• Inventors: Miles, Patrick, Martinelli, Scot, Finley, Eric, Gharib, James, Farquhar, Allen, Kaula, Norbert, Blewett, Jeffrey
• Primary Examiner(s): Robert, Eduardo C
• Assistant Examiner(s): COTRONEO, STEVEN J
• Application Number:
  US12/725,685
• Publication Number:
  US 20100174148A1
• Time in Patent Office: 783 Days
• Field of Search: 600201-246, 600185-200, 606/107
• US Class Current: 600/202
• CPC Class Codes: A61B 1/32 Devices for opening or enlarging the visual field, e.g. of a tube of the body dilators A61M29/00
• CPC Class Codes: A61B 17/0206 with antagonistic arms as supports for retractor elements
• CPC Class Codes: A61B 17/0218 for minimally invasive surgery A61B17/0281, A61B17/0469, A61B17/12013, A61B17/1285, A61B17/29, A61B17/320016 take precedence
• CPC Class Codes: A61B 17/025 Joint distractors
• CPC Class Codes: A61B 2017/00473 Distal part, e.g. tip or head A61B2017/00464 takes precedence
• CPC Class Codes: A61B 2017/0262 with a provision for protecting nerves
• CPC Class Codes: A61B 5/4893 Nerves

Abstract

A surgical access system including a tissue distraction assembly and a tissue refraction assembly, both of which may be equipped with one or more electrodes for use in detecting the existence of (and optionally the distance and/or direction to) neural structures before, during, and after the establishment of an operative corridor to a surgical target site.

Claims

1. A system for forming an operating corridor to a lumbar spine, comprising:

plurality of sequential dilators of increasing diameters to create a tissue distraction corridor along a lateral, trans-psoas path through bodily tissue to a targeted intervertebral disc of a lumbar spine, at least one of the sequential dilators comprising a stimulation electrode along a distal region to deliver electrical stimulation for nerve monitoring when the sequential dilator is positioned in the lateral, trans-psoas path, said at least one of the sequential dilators comprising a proximal connector portion for releasable electrical connection with a nerve monitoring system;

a bladed retractor assembly comprising a plurality of retractor blades that are simultaneously slidable over an outermost dilator of the plurality of sequential dilators along the lateral, trans-psoas path to enlarge the tissue distraction corridor and thereby form an operative corridor along the lateral, trans-psoas path to the targeted intervertebral disc of the lumbar spine, wherein the bladed retractor assembly is adjustable from a first position in which the plurality of retractor blades are positioned to slide over the outermost dilator of the plurality of sequential dilators to a second position in which the plurality of retractor blades are spaced apart from one another to enlarge the tissue distraction corridor,

wherein when the bladed retractor assembly forms the operative corridor along the lateral, trans-psoas path to the targeted intervertebral disc of the lumbar spine, the operative corridor is dimensioned so as to pass an implant through the operative corridor along the lateral, trans-psoas path toward the targeted intervertebral disc of the lumbar spine.

2. The system of claim 1, wherein the bladed retractor assembly further comprises movable arm portions to adjust the bladed retractor assembly from the first position to the second position.

3. The system of claim 2, wherein the plurality of retractor blades extend generally perpendicularly relative to the movable arm portions.

4. The system of claim 1, further comprising an elongate member deliverable to the targeted intervertebral disc along the lateral, trans-psoas path such that a distal tip region of the elongate member penetrates into an annulus of the targeted intervertebral disc, the distal tip region of the elongate member including a stimulation electrode that delivers electrical stimulation for nerve monitoring during advancement of the elongate member along the lateral, trans-psoas path to the lumbar spine.

5. The system of claim 4, wherein the elongate member is advanced together with an initial dilator along the lateral, trans-psoas path.

6. The system of claim 4, wherein the elongate member comprises a K-wire.

7. The system of claim 1, wherein the bladed retractor assembly further comprises a fixation element to releasably engage with one of the retractor blades so that at least a portion of the fixation element extends distally from the one of the retractor blades to penetrate into the lumbar spine.

8. The system of claim 7, wherein the fixation element comprises a shim member that at least partially extends distally from the one of the retractor blades to anchor into the targeted intervertebral disc.

9. The system of claim 1, further comprising the nerve monitoring system configured to deliver an electrical stimulation signal to the stimulation electrode when said at least one of the sequential dilators is positioned along the lateral, trans-psoas path, the nerve monitoring system being configured to monitor electrical activity detected by a set of sensor electrodes in communication with leg muscle myotomes associated with nerves in the vicinity of the targeted intervertebral disc, and the nerve monitoring system being configured to display to a user a numeric stimulation current threshold required to obtain the detected electrical activity in at least one of said leg muscle myotomes.

10. The system of claim 1, wherein at least two refractor blades of the plurality of retractor blades are configured to simultaneously move during adjustment the bladed retractor assembly from the first position to the second position.

11. The system of claim 1, wherein the bladed retractor assembly further comprises a blade holder apparatus configured to adjust a position of the plurality of retractor blades.

12. The system of claim 11, wherein the plurality of retractor blades extend generally perpendicularly relative to movable arm portions of the blade holder apparatus.

13. The system of claim 11, wherein the blade holder apparatus comprises a handle assembly including first and second first arm members that are hingedly coupled.

14. A system for forming an operating corridor to a lumbar spine, comprising:

plurality of sequential dilators of increasing diameters to create a tissue distraction corridor along a lateral, trans-psoas path through bodily tissue to a targeted intervertebral disc of a lumbar spine, each of the sequential dilators comprising a stimulation electrode along a distal region to deliver electrical stimulation for nerve monitoring during advancement of the sequential dilator along the lateral, trans-psoas path through the bodily tissue to the targeted intervertebral disc of the lumbar spine, each of the sequential dilators comprising a proximal connector portion for electrical connection with a nerve monitoring system;

the nerve monitoring system delivering an electrical stimulation signal to the stimulation electrode of each of the sequential dilators during advancement of the sequential dilator along the lateral, trans-psoas path through the bodily tissue to the targeted intervertebral disc of the lumbar spine, the nerve monitoring system monitoring electromyographic (EMG) activity detected by a set of sensor electrodes in communication with leg muscle myotomes associated with nerves in the vicinity of the targeted intervertebral disc, and the nerve monitoring system displaying to a user a numeric stimulation current threshold required to obtain the detected EMG activity in at least one of said leg muscle myotomes;

a bladed retractor assembly comprising a plurality of retractor blades that are simultaneously slidable over an outermost dilator of the plurality of sequential dilators along the lateral, trans-psoas path to enlarge the tissue distraction corridor and thereby form an operative corridor along the lateral, trans-psoas path to the targeted intervertebral disc of the lumbar spine, wherein the bladed retractor assembly is adjustable from a closed position in which the plurality of retractor blades are adjacent to one another and slidable over the outermost dilator of the plurality of sequential dilators to an opened position in which the plurality of retractor blades are spaced apart from one another,

wherein when the bladed retractor assembly forms the operative corridor along the lateral, trans-psoas path to the targeted intervertebral disc of the lumbar spine, the operative corridor is dimensioned so as to pass an implant through the operative corridor along the lateral, trans-psoas path toward the targeted intervertebral disc of the lumbar spine.

15. The system of claim 14, wherein the nerve monitoring system comprises a control unit having a video display device, a patient module connected to the control unit via a data cable, an EMG sensor harness having the set of sensor electrodes connected to the patient module, wherein the control unit receives signals from the patient module and processes EMG responses received from the sensor electrodes to extract characteristic information for each of said leg muscle myotomes.

16. The system of claim 14, wherein the bladed retractor assembly further comprises a handle assembly that is actuatable to adjust the bladed refractor assembly from the closed position to the opened position.

17. The system of claim 16, wherein the plurality of retractor blades extend generally perpendicularly relative to arm portions of the handle assembly.

18. The system of claim 14, further comprising an elongate guide member deliverable to the targeted intervertebral disc along the lateral, trans-psoas path such that a distal tip region of the elongate guide member penetrates into an annulus of the targeted intervertebral disc, the distal tip region of the elongate guide member including a stimulation electrode that delivers electrical stimulation for nerve monitoring during advancement of the elongate guide member along the lateral, trans-psoas path to the lumbar spine.

19. The system of claim 18, wherein the elongate guide member is advanced together with the initial dilator along the lateral, trans-psoas path.

20. The system of claim 18, wherein the elongate guide member comprises a K-wire.

21. The system of claim 14, wherein the bladed retractor assembly further comprises a fixation element to releasably engage with one of the retractor blades so that at least a portion of the fixation element extends distally from the one of the retractor blades to penetrate into the lumbar spine.

22. The system of claim 21, wherein the fixation element comprises a shim member that at least partially extends distally from the one of the retractor blades to anchor into the targeted intervertebral disc.

23. A method of forming an operating corridor to a lumbar spine, comprising:

inserting a first sequential dilator of a plurality of sequential dilators along a lateral, trans-psoas path through bodily tissue to a targeted intervertebral disc of a lumbar spine, wherein a first stimulation electrode at a distal region of the first sequential dilator is configured to deliver electrical stimulation for nerve monitoring when the first sequential dilator is positioned in the lateral, trans-psoas path, the first sequential dilator comprising a first proximal connector portion for electrical connection with a nerve monitoring system;

slidably advancing a second sequential dilator of the plurality of sequential dilators over the first sequential dilator along the lateral, trans-psoas path to the targeted intervertebral disc of the lumbar spine, wherein a second stimulation electrode at a distal region of the second sequential dilator is configured to deliver electrical stimulation for nerve monitoring when the second sequential dilator is positioned in the lateral, trans-psoas path, the second sequential dilator comprising a second proximal connector portion for electrical connection with the nerve monitoring system, wherein the plurality of sequential dilators create a tissue distraction corridor along the lateral, trans-psoas path through the bodily tissue to the targeted intervertebral disc of the lumbar spine;

simultaneously delivering a plurality of retractor blades of a retractor assembly over an outermost dilator of the plurality of sequential dilators along the lateral, trans-psoas path to enlarge the tissue distraction corridor and thereby form an operative corridor along the lateral, trans-psoas path to the targeted intervertebral disc of the lumbar spine, wherein the retractor assembly is adjustable from a first position in which the plurality of retractor blades are positioned to slide over the outermost dilator of the plurality of sequential dilators to a second position in which the plurality of retractor blades are spaced apart from one another; and

after the retractor assembly forms the operative corridor along the lateral, trans-psoas path to the targeted intervertebral disc of the lumbar spine, passing an implant through the operative corridor along the lateral, trans-psoas path toward the targeted intervertebral disc of the lumbar spine.

24. The method of claim 23, further comprising actuating a blade holder assembly of the retractor assembly to adjust the retractor assembly from the first position to the second position.

25. The method of claim 24, wherein the plurality of retractor blades extend generally perpendicularly relative to arm portions of the blade holder assembly.

26. The method of claim 23, further comprising delivering an elongate guide member to the targeted intervertebral disc along the lateral, trans-psoas path such that a distal tip region of the elongate guide member penetrates into an annulus of the targeted intervertebral disc, the distal tip region of the elongate guide member including a stimulation electrode that delivers electrical stimulation for nerve monitoring during delivery of the elongate guide member along the lateral, trans-psoas path to the lumbar spine.

27. The method of claim 26, wherein the elongate guide member is delivered together with the initial dilator along the lateral, trans-psoas path.

28. The method of claim 26, wherein the elongate guide member comprises a K-wire.

29. The method of claim 23, further comprising releasably engaging a fixation element with one of the refractor blades so that at least a portion of the fixation element extends distally from the one of the retractor blades to penetrate into the lumbar spine.

30. The method of claim 29, wherein the fixation element comprises a shim member that at least partially extends distally from the one of the retractor blades to anchor into the targeted intervertebral disc.

31. The method of claim 23, further comprising:

electrically connecting a cable of the nerve monitoring system to the first proximal connector portion of first sequential dilator, wherein the nerve monitoring system delivers an electrical stimulation signal to the first stimulation electrode of the first sequential dilators during insertion of the first sequential dilator along the lateral, trans-psoas path through the bodily tissue to the targeted intervertebral disc of the lumbar spine, the nerve monitoring system monitoring electromyographic (EMG) activity detected by a set of sensor electrodes in communication with leg muscle myotomes associated with nerves in the vicinity of the targeted intervertebral disc, and the nerve monitoring system displaying to a user a numeric stimulation current threshold required to obtain the detected EMG activity in at least one of said leg muscle myotomes during insertion of the first sequential dilator; and

after the first sequential dilator is inserted along the lateral, trans-psoas path, electrically connecting said cable of the nerve monitoring system to the second proximal connector portion of second sequential dilator, wherein the nerve monitoring system delivers an electrical stimulation signal to the second stimulation electrode of the second sequential dilators during advancement of the second sequential dilator along the lateral, trans-psoas path through the bodily tissue to the targeted intervertebral disc of the lumbar spine, the nerve monitoring system monitoring electromyographic (EMG) activity detected by the set of sensor electrodes in communication with the leg muscle myotomes associated with nerves in the vicinity of the targeted intervertebral disc, and the nerve monitoring system displaying to the user the numeric stimulation current threshold required to obtain the detected EMG activity in at least one of said leg muscle myotomes during advancement of the second sequential dilator.

32. The method of claim 31, wherein the nerve monitoring system comprises a control unit having a video display device, a patient module connected to the control unit via a data cable, an EMG sensor harness having the set of sensor electrodes connected to the patient module, wherein the control unit receives signals from the patient module and processes EMG responses received from the sensor electrodes to extract characteristic information for each of said leg muscle myotomes.

33. The method of claim 23, wherein at least two retractor blades of the plurality of retractor blades are configured to simultaneously move during adjustment the retractor assembly from the first position to the second position.