Surgical access system and related methods

• US 8,192,356 B2
• Filed: 12/10/2009
• Issued: 06/05/2012
• Est. Priority Date: 06/26/2002
• Status: Expired due to Fees

• 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): Philogene, Pedro
• Application Number:
  US12/635,418
• Publication Number:
  US 20100094093A1
• Time in Patent Office: 908 Days
• Field of Search: 600/221, 600/215, 600/202, 600/210, 600/546, 600/223, 600/201, 600/214, 600/224, 600/219, 607/131, 607/130, 607/129, 607/117, 607/119, 607/43, 607/2, 606/90, 606/324, 606/99, 606/129
• 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 17/025 Joint distractors
• CPC Class Codes: A61B 17/0293 with ring member to support retractor elements
• CPC Class Codes: A61B 2017/00026 Conductivity or impedance, e.g. of tissue
• CPC Class Codes: A61B 2017/00039 Electric or electromagnetic phenomena other than conductivity, e.g. capacity, inductivity, Hall effect
• CPC Class Codes: A61B 2017/0256 for the spine
• CPC Class Codes: A61B 2017/0262 with a provision for protecting nerves
• CPC Class Codes: A61B 5/296 for electromyography [EMG]
• CPC Class Codes: A61B 5/4893 Nerves
• CPC Class Codes: A61B 5/7405 using sound
• CPC Class Codes: A61B 5/742 using visual displays A61B5/339 takes precedence

Abstract

A system for accessing a surgical target site and related methods, involving an initial distraction system for creating an initial distraction corridor, and an assembly capable of distracting from the initial distraction corridor to a secondary distraction corridor and thereafter sequentially receiving a plurality of retractor blades for retracting from the secondary distraction corridor to thereby create an operative corridor to the surgical target site, 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 spinal disc of a lumbar spine through an operative corridor, comprising:

a distraction assembly to create a tissue distraction corridor to a lumbar spine, wherein said distraction assembly comprises an elongate stimulation member deliverable to a spinal disc along a lateral, trans-psoas path to the lumbar spine such that a distal tip region of the elongate stimulation member is configured to engage an annulus of a spinal disc in the lumbar spine, the distal tip region of the elongate stimulation member including a stimulation electrode to deliver electrical stimulation for nerve monitoring when the elongate stimulation member is positioned in the lateral, trans-psoas path to the lumbar spine, the distraction assembly further comprising a dilator system comprising at least one dilator that slidably engages an exterior of the elongate stimulation member, the at least one dilator being deliverable to the spinal disc along the lateral, trans-psoas path to the lumbar spine; and

a retraction assembly comprising a plurality of retractor blades that enlarge the tissue distraction corridor to thereby form an operative corridor along the lateral, trans-psoas path to the lumbar spine when the plurality of retractor blades are delivered to the lumbar spine, wherein one of the retractor blades is a posterior-most retractor blade when the plurality of retractor blades are delivered to the lumbar spine, the retraction assembly further comprising a locking member that releasably and slidably engages with the posterior-most retractor blade so that a distal portion of the locking member extends distally from the posterior-most retractor blade, wherein the distal portion of the locking member anchors into the spinal disc between adjacent vertebral bodies and secures the posterior-most retractor blade relative to the adjacent vertebral bodies when the plurality of retractor blades are delivered to the lumbar spine,

wherein when the plurality of retractor blades enlarge the tissue distraction corridor to form the operative corridor along the lateral, trans-psoas path to the lumbar spine, the operative corridor is dimensioned so as to pass an implant through the operative corridor along the lateral, trans-psoas path to the lumbar spine.

2. The system of claim 1, further comprising an introducer tool the releasably engages a coupling region of the locking member during engagement of the locking member to the posterior-most retractor blade.

3. The system of claim 2, wherein locking member releasably and slidably engages a receiving passageway formed in the posterior-most retractor blade.

4. The system of claim 3, wherein when the plurality of retractor blades are delivered to the lumbar spine, the distal portion of the locking member is movable into a press-fit, secure engagement between the adjacent vertebrae to thereby maintain a position of the posterior-most retractor blade relative to the adjacent vertebrae.

5. The system of claim 4, wherein the distal portion of the locking member comprises a narrowed tip portion that is smaller than the coupling region of the locking member.

6. The system of claim 5, wherein the locking member has a smallest width at a rounded distal tip of the narrowed tip portion.

7. The system of claim 6, wherein the retractor assembly further comprises a plurality of light emitting devices to direct light through the operative corridor toward the spinal disc, the plurality of light emitting devices being coupled to the plurality of retractor blades.

8. The system of claim 1, wherein the plurality of retractor blades comprises a second retractor blade that is spaced apart from the posterior-most retractor blade when the plurality of retractor blades enlarge the tissue distraction corridor to form the operative corridor along the lateral, trans-psoas path to the lumbar spine.

9. The system of claim 8, wherein the second retractor blade is an anterior-most retractor blade when the plurality of retractor blades are delivered to the lumbar spine.

10. The system of claim 8, wherein the retractor assembly further comprises a second locking member that releasably and slidably engages with the second retractor blade so that a distal portion of the second locking member extends distally from the second retractor blade.

11. The system of claim 10, wherein the distal portion of the second locking member anchors into the lumbar spine and secures the second retractor blade relative to the lumbar spine when the plurality of retractor blades are delivered to the lumbar spine.

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

13. The system of claim 1, wherein the dilator system of the distraction assembly further comprises a second dilator that slidably engages an exterior of the at least one dilator which slidably engages the exterior of the elongate stimulation member.

14. The system of claim 13, wherein each of the dilators of the dilator system comprises a stimulation electrode to deliver electrical stimulation for nerve monitoring.

15. The system of claim 1, wherein the distraction assembly further comprises a secondary distraction assembly.

16. The system of claim 15, wherein the second distraction assembly comprises a speculum instrument that is slidable along the dilator system to prepare the tissue distraction corridor for receipt of the plurality of retractor blades.

17. The system of claim 1, wherein each of the plurality of retractor blades comprises a stimulation electrode to deliver electrical stimulation for nerve monitoring.

18. The system of claim 1, further comprising a monitoring system that delivers an electrical stimulation signal to the stimulation electrode of the elongate stimulation member, monitors electromyographic activity detected by a set of sensor electrodes in muscle myotomes associated with nerves in the vicinity of the spinal disc, and displays to a user:

a numeric stimulation threshold required to obtain the electromyographic activity in at least one of said muscle myotomes, and myotomes levels being monitored.

19. The system of claim 18, 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.

20. The method of claim 19, 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 muscle myotomes.

21. A system for accessing a spinal disc of a lumbar spine through an operative corridor, comprising:

a distraction assembly to create a tissue distraction corridor to a lumbar spine, wherein said distraction assembly comprises;

an elongate penetration member deliverable to a spinal disc along a lateral, trans-psoas path to the lumbar spine such that a distal tip region of the elongate penetration member penetrates into an annulus of a spinal disc in the lumbar spine, and at least two dilators of sequentially larger diameter deliverable to the spinal disc along the lateral, trans-psoas path to the lumbar spine, a first dilator of the at least two dilators having a lumen configured to slidably receive the elongate penetration member, at least one of said at least two dilators including a stimulation electrode to deliver electrical stimulation for nerve monitoring when said stimulation electrode is positioned in the lateral, trans-psoas path to the lumbar spine; and

a retraction assembly comprising a plurality of retractor blades that enlarge the tissue distraction corridor to thereby form an operative corridor along the lateral, trans-psoas path to the lumbar spine when the plurality of retractor blades are delivered to the lumbar spine, the retraction assembly further comprising a blade holder apparatus that is configured to releasably lock with the plurality of retractor blades,

wherein when the plurality of retractor blades enlarge the tissue distraction corridor to form the operative corridor along the lateral, trans-psoas path to the lumbar spine, the operative corridor is dimensioned so as to pass an implant through the operative corridor along the lateral, trans-psoas path to the lumbar spine.

22. The system of claim 21, further comprising a plurality of extension members, each extension member releasably and slidably engaging with a respective retractor blade of the plurality of retractor blades so that a distal portion of each extension member extends distally from its respective retractor blade, wherein the distal portion of each extension member engages with the lumbar spine when the plurality of retractor blades are delivered to the lumbar spine.

23. The system of claim 22, wherein when the plurality of retractor blades are delivered to the lumbar spine, the distal portion of the each extension is adapted to anchorinto the spinal disc between adjacent vertebral bodies and secures its respective retractor blade relative to the adjacent vertebral bodies.

24. The system of claim 22, wherein the distal portion of each extension member comprises a narrowed tip portion that is smaller than a proximal region of the extension member.

25. The system of claim 24, wherein each extension member has a smallest width at a rounded distal tip of the narrowed tip portion.

26. The system of claim 25, wherein the retractor assembly further comprises a plurality of light emitting devices to direct light through the operative corridor toward the spinal disc, the plurality of light emitting devices being coupled to the plurality of retractor blades.

27. The system of claim 21, wherein the plurality of retractor blades comprises a first retractor blade and a second retractor blade that is spaced apart from the first retractor blade when the plurality of retractor blades enlarge the tissue distraction corridor to form the operative corridor along the lateral, trans-psoas path to the lumbar spine.

28. The system of claim 27, wherein the first retractor blade is a posterior-most retractor blade and the second retractor blade is an anterior-most retractor blade when the plurality of retractor blades are delivered to the lumbar spine.

29. The system of claim 21, wherein the elongate penetration member comprises a K-wire.

30. The system of claim 21, wherein a second dilator of the at least two dilators slidably engages an exterior of the first dilator which slidably engages the exterior of the elongate penetration member.

31. The system of claim 21, wherein the distraction assembly further comprises a secondary distraction assembly.

32. The system of claim 31, wherein the secondary distraction assembly comprises a speculum instrument that is slidable along the dilator system to prepare the tissue distraction corridor for receipt of the plurality of retractor blades.

33. The system of claim 21, wherein each retractor blade of the plurality of retractor blades comprises a stimulation electrode to deliver electrical stimulation for nerve monitoring.

34. The system of claim 21, further comprising a monitoring system that delivers an electrical stimulation signal to the stimulation electrode of the at least two dilators, monitors electromyographic activity detected by a set of sensor electrodes in muscle myotomes associated with nerves in the vicinity of the spinal disc.

35. The system of claim 34, wherein the monitoring system displays to a user a numeric stimulation threshold value required to obtain the electromyographic activity in at least one of said muscle myotomes along with the myotomes levels being monitored.

36. The system of claim 34, 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.

37. The method of claim 36, 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 muscle myotomes.