System and methods for performing surgical procedures and assessments

• US 8,244,343 B2
• Filed: 08/23/2011
• Issued: 08/14/2012
• Est. Priority Date: 09/25/2001
• Status: Expired due to Term

• Current Assignee: Nuvasive Incorporated
• Original Assignee: Nuvasive Incorporated
• Inventors: Gharib, James, Farquhar, Allen, Kaula, Norbert F., Blewett, Jeffrey J., Finley, Eric, Martinelli, Scot
• Primary Examiner(s): Hindenburg, Max
• Assistant Examiner(s): Foreman, Jonathan M.
• Application Number:
  US13/215,791
• Publication Number:
  US 20110313530A1
• Time in Patent Office: 357 Days
• Field of Search: 600/546, 600/554, 606/32, 606/41, 607/115, 607/116, 607/117, 623/17.11
• US Class Current: 600/546
• 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 17/0218 for minimally invasive surgery A61B17/0281, A61B17/0469, A61B17/12013, A61B17/1285, A61B17/29, A61B17/320016 take precedence
• CPC Class Codes: A61B 17/3417 Details of tips or shafts, e.g. grooves, expandable, bendable; Multiple coaxial sliding cannulas, e.g. for dilating syringe needles A61M5/32; dilators A61M29/00
• CPC Class Codes: A61B 17/3421 Cannulas
• CPC Class Codes: A61B 17/3423 Access ports, e.g. toroid shape introducers for instruments or hands access sites for liquids A61M39/0247
• CPC Class Codes: A61B 2017/00039 Electric or electromagnetic phenomena other than conductivity, e.g. capacity, inductivity, Hall effect
• CPC Class Codes: A61B 2017/00199 with a console, e.g. a control panel with a display
• CPC Class Codes: A61B 2017/0262 with a provision for protecting nerves
• CPC Class Codes: A61B 2034/2053 Tracking an applied voltage gradient
• CPC Class Codes: A61B 2034/2072 Reference field transducer attached to an instrument or patient
• CPC Class Codes: A61B 34/20 Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
• CPC Class Codes: A61B 34/25 User interfaces for surgical systems
• CPC Class Codes: A61B 5/24 Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
• CPC Class Codes: A61B 5/296 for electromyography [EMG]
• CPC Class Codes: A61B 5/4893 Nerves
• CPC Class Codes: A61B 5/6828 Leg
• CPC Class Codes: A61B 5/6831 Straps, bands or harnesses
• CPC Class Codes: A61B 90/36 Image-producing devices or illumination devices not otherwise provided for
• CPC Class Codes: A61B 90/37 Surgical systems with images on a monitor during operation
• CPC Class Codes: A61F 2/4455 for the fusion of spinal bodies, e.g. intervertebral fusion of adjacent spinal bodies, e.g. fusion cages intervertebral discs A61F2/442
• CPC Class Codes: A61F 2/4611 : of spinal prostheses
• CPC Class Codes: A61F 2002/4635 : using minimally invasive surgery
• CPC Class Codes: A61N 1/0551 : Spinal or peripheral nerve electrodes
• CPC Class Codes: A61N 1/0553 : Paddle shaped electrodes, e.g. for laminotomy
• CPC Class Codes: A61N 1/36142 : for improving safety
• CPC Class Codes: A61N 1/37247 : User interfaces, e.g. input or presentation means

Abstract

The present invention involves systems and related methods for performing surgical procedures and assessments, including the use of neurophysiology-based monitoring to: (a) determine nerve proximity and nerve direction to surgical instruments employed in accessing a surgical target site; (b) assess the pathology (health or status) of a nerve or nerve root before, during, or after a surgical procedure; and/or (c) assess pedicle integrity before, during or after pedicle screw placement, all in an automated, easy to use, and easy to interpret fashion so as to provide a surgeon-driven system.

Claims

1. A system for inserting a spinal implant through a trans-psoas operative corridor to an intervertebral disc, comprising:

an elongate stimulation instrument to advance in a trans-psoas path through bodily tissue toward a lateral aspect of the targeted intervertebral disc of the lumbar spine, the elongate stimulation instrument comprising;

an elongate body, a distal tip portion configured to engage an annulus of the targeted intervertebral disc, and a stimulation electrode exposed along the distal tip portion to emit an electrical stimulation signal to the bodily tissue for nerve monitoring while the elongate stimulation instrument is positioned in the trans-psoas path through the bodily tissue;

a plurality of trans-psoas dilators of increasing diameters to dilate the trans-psoas path through the bodily tissue toward the lateral aspect of the targeted intervertebral disc of the lumbar spine, the plurality of dilators comprising;

an first dilator to slidably engage with an exterior of the elongate stimulation instrument and having a first length,

a second dilator to slidably engage with an exterior of the initial dilator and having a second length less than the first length of the initial dilator, wherein the second dilator comprises;

a proximal connector region configured to releasably mate with an electrical cable of a nerve monitoring system, and a stimulation electrode exposed along a tapered distal tip region of the second dilator to emit an electrical stimulation signal to the bodily tissue for nerve monitoring while the second dilator is positioned in the trans-psoas path, and

a third dilator to slidably engage with an exterior of the second dilator and having a third length less than the second length of the second dilator, wherein the third dilator comprises;

a proximal connector region configured to releasably mate with the electrical cable of a nerve monitoring system, and a stimulation electrode exposed along a tapered distal tip region of the third dilator to emit an electrical stimulation signal to the bodily tissue for nerve monitoring while the third dilator is positioned in the trans-psoas path;

a working corridor instrument slidable over an outermost of the plurality of trans-psoas dilators along the trans-psoas path through the bodily tissue to the lateral aspect of the targeted intervertebral disc of the lumbar spine, the working corridor instrument being configured to enlarge the trans-psoas path through the bodily tissue and define a trans-psoas operative corridor along the trans-psoas path through the bodily tissue toward the lateral aspect of the targeted intervertebral disc of the lumbar spine, wherein the trans-psoas operative corridor defined by the working corridor instrument is dimensioned so as to pass a spinal fusion implant through the trans-psoas operative corridor to the targeted intervertebral disc of the lumbar spine.

2. The system of claim 1, wherein the working corridor instrument has an insertion length configured to extend through the bodily tissue to the lateral aspect of the targeted intervertebral disc, the insertion length of the working corridor instrument being less than the third length of the third dilator.

3. The system of claim 2, wherein the working corridor instrument comprises an external proximal portion that has a maximum width greater than a maximum lateral width of the trans-psoas operative corridor to be defined by the working corridor instrument.

4. The system of claim 1, further comprising a nerve monitoring system that delivers the electrical stimulation signal to the stimulation electrode of the elongate stimulation instrument, monitors electromyographic activity detected by a set of sensor electrodes in leg muscle myotomes associated with nerves in the vicinity of the lumbar spine, and displays a numeric stimulation threshold required to obtain the electromyographic activity in at least one of said leg muscle myotomes.

5. The system of claim 4, wherein the 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.

6. The system of claim 5, wherein the control unit receives signals from the patient module and processes EMG responses output from the sensor electrodes to extract characteristic information for each of said leg muscle myotomes.

7. The system of claim 4, wherein the monitoring system displays said numeric stimulation threshold in the form of a numeric value of an electrical current.

8. The system of claim 1, wherein the plurality of trans-psoas dilators and the elongate stimulation instrument are removable from the working corridor instrument after the working corridor instrument advances to the lateral aspect of the targeted intervertebral disc of the lumbar spine to establishing the trans-psoas operative corridor to the intervertebral disc of the spine.

9. The system of claim 1, further comprising an electrical cable for a nerve monitoring system, wherein a distal end of the electrical cable includes a connector device that is shaped to releasably receive the proximal connector region of the second dilator and to releasably receive the proximal connector region of the third dilator.

10. The system of claim 1, wherein the working corridor instrument is shaped to define a generally cylindrical operative corridor.

11. The system of claim 1, wherein the elongate stimulation instrument is configured to advance together with the initial dilator in the trans-psoas path through the bodily tissue toward the lateral aspect of the targeted intervertebral disc of the lumbar spine.

12. The system of claim 1, wherein the elongate stimulation instrument comprises a K-wire.

13. The system of claim 1, wherein the working corridor instrument comprises a working cannula that defines a lumen.