Surgical access system and related methods

• US 20090124860A1
• Filed: 02/27/2004
• Published: 05/14/2009
• Est. Priority Date: 02/27/2003
• 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 7,819,801 B2
• Time in Patent Office: Days
• 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 17/02 for holding wounds open; Tractors specula A61B1/32 ; drainage appliances for wounds A61M27/00
• 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 2017/0256 for the spine
• CPC Class Codes: A61B 5/24 Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof

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, comprising:

a handle assembly including a first arm member, a second arm member hingedly attached to said first arm member, and a translating member adapted to move longitudinally relative said first and second arm members;

a first retractor blade rigidly coupled to said first arm member prior to introduction into said surgical target site, a second retractor blade rigidly coupled to said second arm member prior to introduction into said surgical target site, and a third retractor blade rigidly coupled to said translating member prior to introduction into said surgical target site;

said handle being configured to simultaneously introduce said first, second and third retractor blades to said surgical target site in a closed position and thereafter opened by manually squeezing said first and second arm members relative to one another to create an operative corridor to said surgical target site.

2. The system of claim 1, further comprising a a K-wire configured to be initially advanced to said surgical target site, at least one generally cylindrical dilator configured to be slideably passed over said K-wire and secondarily advanced to said surgical target site, said at least one generally cylindrical dilator having an outer diameter slightly smaller than an inner diameter of said first, second and third retractor blades while in said closed position.

3. The system of claim 1 and further, comprising at least one shim element capable of being detachably engaged with at least one of said first, second and third retractor blades, said shim element having an extension of sufficient length to extend past a distal end of said at least one of said first, second and third retractor blades into a spinal disc space and of sufficient height to distract vertebral bodies adjacent to said spinal disc space.

4. The system of claim 1 and further, comprising at least one retractor extender capable of being detachably engaged with at least one of said first, second and third retractor blades, said retractor extender having a width wider than said at least one of said first, second and third retractor blade to prevent the ingress of adjacent tissue into said operative corridor after said first, second and third retractor blades have been opened.

5. The system of claim 2, wherein at least one of said K-wire, said at least one dilator, and at least one of said first, second and third retractor blades are equipped with at least one stimulation electrode.

6. The system of claim 5, 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 at least one of proximity and direction between said at least one stimulation electrode and said depolarized nerve based upon the sensed response, and communicating said at least one of proximity and direction to a user.

7. The system of claim 6, 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.

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

9. The system of claim 1, wherein said system for establishing an operative corridor to a surgical target site is configured to access a spinal target site.

10. The system of claim 1, wherein said system is configured to establish said operative corridor via a lateral, trans-psoas approach.

11. The system of claim 6, further comprising at least one button for initiating the electrical stimulation from said control unit to said at least one stimulation electrode.

12. The system of claim 6, wherein the control unit comprises a display operable to display at least one of an electromyographic (EMG) response of said muscle coupled to said depolarized nerve and a stimulation threshold of said depolarized nerve.

13. The system of claim 6, wherein the control unit comprises a touch-screen display operable to receive commands from a user.

14. The system of claim 6, wherein said stimulation electrodes are positioned near a distal end of at least one of said K-wire, said at least one generally cylindrical dilator, and said at least one of said first, second and third retractor blades.

15. A method of accessing a surgical target site, comprising the steps of:

advancing at least one generally cylindrical dilator to said surgical target site;

thereafter advancing over said at least one dilator a retractor assembly including a first retractor blade, a second retractor blade and a third retractor blade releasably coupled to a hinged handle assembly while said first, second and third retractor blades are positioned generally adjacent to one another in a closed position; and

thereafter manually squeezing said hinged handle assembly to move said first, second and third retractor blades into an open position to create an operative corridor to said surgical target site.

16. The method of claim 15, wherein said step of advancing at least one dilator is preceded by advancing a K-wire to said surgical target site and thereafter slidably passing said at least dilator over said K-wire.

17. The method of claim 15, including the step of detachably engaging at least one shim element having an extension to at least one of said first second and third retractor blades after said first, second and third retractor blades have been advanced to said surgical target site and thereafter advancing said shim element such that said extension extends past a distal end of said at least one of said first, second and third retractor blades into a spinal disc space and distracts vertebral bodies adjacent to said spinal disc space.

18. The method of claim 17, wherein said at least one shim element is detachably coupled to said third retractor blade, which is disposed near the posterior region of the spine.

19. The method of claim 15, further comprising the step of performing neuromonitoring during at least one of the steps of advancing said at least one dilator, advancing said retractor assembly over said at least one dilator, and after said retractor assembly has been manually opened by squeezing said hinged handle assembly.