Surgical access system and related methods

• US 20080097164A1
• Filed: 01/16/2004
• Published: 04/24/2008
• Est. Priority Date: 01/16/2003
• Status: Active Grant

• Current Assignee: Nuvasive Incorporated
• Original Assignee: Nuvasive Incorporated
• Inventors: Martinelli, Scot, Finley, Eric, Miles, Patrick, Blewett, Jeffrey, Kaula, Norbert, Gharib, James, Farquhar, Allen, Medeiros, Goretti
• Granted Patent: US 7,691,057 B2
• Time in Patent Office: Days
• US Class Current: 600/219
• 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 retraction 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 accessing a surgical target site within a spine, comprising:

a distraction assembly adapted to create a distraction corridor to said surgical target site;

a primary retractor assembly having a handle assembly and a first retractor blade, a second retractor blade, and a third retractor blade removably coupled to said handle assembly, said handle assembly adapted to move said first, second and third retractor blades between a closed position and an open position, said closed position being characterized by said first, second and third retractor blades being positioned generally adjacent to one another, said open position being characterized by said first, second and third retractor blades being positioned generally away from one another, wherein said first, second and third retractor blades are adapted to be introduced simultaneously over said distraction assembly while in said closed position to said surgical target site and thereafter moved to said open position to create and maintain an operative corridor to said surgical target site; and

a supplemental retractor assembly having an arm with a fourth retractor blade removably coupled to said arm, said arm adapted to be selectively coupled to said handle assembly of said primary retractor assembly, and said fourth retractor blade adapted to be introduced into said surgical target site and moved to expand said operative corridor.

2. The system of claim 1, wherein said distraction assembly includes a K-wire adapted to be introduced to said surgical target site and an initial dilator capable of being slideably passed over said K-wire to perform initial distraction.

3. The system of claim 1, wherein said distraction assembly includes a plurality of sequential dilators.

4. The system of claim 2, wherein said initial dilator is a split dilator capable of being split after introduction to perform said initial distraction.

5. The system of claim 1, further comprising at least one shim member adapted to be coupled to at least one of said retractor blades, said shim member including a contiguous extension dimensioned to extend past said retractor blade into the surgical target site.

6. The system of claim 5, wherein at least one of said distraction assembly, one of said retractor blades, and said at least one shim member includes at least one stimulation electrode.

7. The system of claim 6, further comprising a control unit capable of electrically stimulating said at least one stimulation electrode, sensing a response of a nerve depolarized by said stimulation, determining a direction from at least one of said initial distraction system, one of said retractor blades, and said at least one shim member to the nerve based upon the sensed response, and communicating said direction to a user.

8. The system of claim 7, further comprising an electrode configured to sense a neuromuscular response of a muscle coupled to said depolarized nerve, the electrode being operable to send the response to the control unit.

9. The system of claim 2, wherein said K-wire has a first stimulation electrode at a distal tip of the K-wire.

11. The system of claim 1, wherein said system for establishing an operative corridor to a surgical target site within a spine is configured to establish said operative corridor via at least one of a posterior, anterior, postero-lateral, and a lateral, trans-psoas approach.

12. The system of claim 7, further comprising a handle coupled to at least one of said initial distraction assembly, one of said retractor blades, and said at least one shim member, the handle having at least one button for initiating the electrical stimulation from said control unit to said at least one stimulation electrode.

13. The system of claim 7, wherein the control unit comprises a display operable to display an electromyographic (EMG) response of the muscle.

14. The system of claim 7, wherein the control unit comprises a touch-screen display operable to receive commands from a user.

15. The system of claim 7, wherein the stimulation electrodes are positioned near a distal end of at least one of the initial distraction system, one of said retractor blades, and said at least one shim member.

10. (canceled)

16. A method of accessing a surgical target site within a spine, comprising the steps of:

(a) creating a distraction corridor to the surgical target site;

(b) removably coupling a first retractor blade, a second retractor blade, and a third retractor blade to a handle assembly capable of moving said first, second and third retractor blades from a closed position to an open position, said closed position being characterized by said first, second and third retractor blades being positioned generally adjacent to one another and said open position characterized by said first, second and third retractor blades being positioned generally away from one another;

(c) simultaneously introducing said first, second, and third retractor blades into said distraction corridor while in said closed position;

(d) actuating said handle assembly to open first, second and third retractor blades to create an operative corridor to said surgical target site;

(e) coupling a fourth retractor blade to said handle assembly after said first, second, and third retractor blades have been moved to said open position; and

(f) moving said fourth retractor blade to expand said operative corridor.

17. The method of claim 16, wherein said step of creating a distraction corridor is accomplished by introducing a K-wire to said surgical target site and thereafter slideably advancing at least one dilator over said K-wire.

18. The method of claim 17, further comprising a step of performing a secondary distraction from said distraction corridor.

19. The method of claim 18, wherein said step of performing secondary distraction is accomplished by using a sequential dilation system.

20. The method of claim 16, further comprising the steps of performing neuromonitoring during at least one of steps (a), (c), (d), and (f), and communicating the result of said neuromonitoring to a user.