Surgical access system and related methods

• US 20050149035A1
• Filed: 10/18/2004
• Published: 07/07/2005
• Est. Priority Date: 10/17/2003
• Status: Active Grant

• Current Assignee: Nuvasive Incorporated
• Original Assignee: Nuvasive Incorporated
• Inventors: Martinelli, Scot, Finley, Eric, Miles, Patrick, Pimenta, Luiz
• Granted Patent: US 7,905,840 B2
• Time in Patent Office: Days
• US Class Current: 606/86.R
• 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 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. Some embodiments of the surgical access system may be particularly suited for establishing an operative corridor to a surgical target site in the spine. Such an operative corridor may be established through the retroperitoneal space and the psoas muscle during a direct lateral, retroperitoneal approach to the spine.

Claims

1. A method included in providing surgical access to a spinal target site through a substantially lateral, retroperitoneal approach, the method comprising:

inserting at least a portion of a finger through a first incision and into a retroperitoneal space;

piercing the skin with a distal tip of a initial dilator through a second incision, and directing the distal tip of the dilator toward the finger;

using the finger to direct the distal tip of the dilator toward the psoas muscle; and

advancing the distal tip of the initial dilator in a substantially lateral direction through the psoas muscle toward a spinal target site while using a stimulation electrode coupled to the initial dilator to detect nerves proximal to the initial dilator.

2. The method of claim 1, wherein the initial dilator includes at least a K-wire.

3. The method of claim 1, further comprising operating a control unit to electrically stimulate said stimulation electrode, sensing a response of a nerve depolarized by said stimulation, and determining a direction from a surgical accessory to the nerve based upon the sensed response.

4. The method of claim 1, further comprising creating a distraction corridor by advancing one or more secondary dilators over the initial dilator to sequentially widen said distraction corridor.

5. The method of claim 4, wherein creating said distraction corridor comprises detecting nerves using at least one stimulation electrode coupled to at least one of the the secondary dilators.

6. The method of claim 5, wherein detecting nerves includes operating a control unit to electrically stimulate said at least one stimulation electrode, sensing a response of a nerve depolarized by said stimulation, and determining a direction from a surgical accessory to the nerve based upon the sensed response.

7. The method of claim 1, further comprising retracting a distraction corridor to produce a substantially lateral operative corridor to said spinal target site.

8. The method of claim 7, wherein retracting said distraction corridor comprises:

a simultaneously introducing a plurality of retractor blades into said distraction corridor; and

opening said plurality of retractor blades to create an operative corridor to said spinal target site.

9. A method of accessing an spinal target site, comprising:

creating a distraction corridor to an spinal target site through a substantially lateral, retroperitoneal approach, comprising;

inserting a guide member through a first incision into a retroperitoneal space,

inserting a distal end of an initial dilator through a second incision into tissue in a substantially lateral direction toward the spinal target site,

engaging the initial dilator with the guide member proximal to the distal end while guiding the distal end through the retroperitoneal space, and

advancing the initial dilator in a substantially lateral direction toward the spinal target site while using a stimulation electrode coupled to the initial dilator to detect nerves proximal to the initial dilator; and

retracting said distraction corridor to produce an operative corridor to said spinal target site.

10. The method of claim 9, wherein the guide member comprises at least a portion of a finger.

11. The method of claim 9, wherein the initial dilator includes at least a K-wire.

12. The method of claim 9, wherein creating said distraction corridor includes operating one or more secondary dilators to sequentially widen said distraction corridor.

13. The method of claim 12, wherein further comprising detecting nerves using at least one stimulation electrode nerves using at least one stimulation electrode coupled to at least one of the secondary dilators.

14. The method of claim 9, further comprising operating a control unit to electrically stimulate said stimulation electrode, sensing a response of a nerve depolarized by said stimulation, and determining a direction from a surgical accessory to the nerve based upon the sensed response.

15. The method of claim 9, wherein retracting said distraction corridor comprises:

a simultaneously introducing a plurality of retractor blades into said distraction corridor; and

opening said plurality of retractor blades to create an operative corridor to said surgical target site.

16. The method of claim 15, wherein the plurality of retractor blades are simultaneously introduced to the surgical target site while in a generally closed position.

17. The method of claim 15, wherein the plurality of retractor blades are opened by selectively moving said retractor blades to create a customized operative corridor to said surgical target site.