Methods and Devices For Minimally Invasive Spinal Connection Element Delivery

• US 20090143828A1
• Filed: 10/02/2008
• Published: 06/04/2009
• Est. Priority Date: 10/04/2007
• Status: Active Grant

• Current Assignee: DePuy Synthes Products LLC (Johnson & Johnson)
• Original Assignee: DePuy Synthes Products LLC (Johnson & Johnson)
• Inventors: Medeiros, Andrew, Baker, Garth, Beaudoin, Paul, Stad, Shawn
• Granted Patent: US 8,414,588 B2
• Time in Patent Office: Days
• US Class Current: 606/86.A
• CPC Class Codes: A61B 17/7085 for insertion of a longitudinal element down one or more hollow screw or hook extensions, i.e. at least a part of the element within an extension has a component of movement parallel to the extension's axis

Abstract

A device for delivery of a spinal rod to a bone anchor includes an inner tube and an outer tube disposed about at least a portion of the inner tube. The inner tube is adjustable relative to the outer tube along the longitudinal axis of the outer tube between a first position and a second position in which the distal end of the inner tube contacts the bone anchor. A spring is interposed between the inner tube and the outer tube to bias the inner tube distally. A locking member is coupled to the outer tube and is adjustable between a proximal position in which the locking member is spaced apart from the inner tube and a distal position in which the locking member inhibits proximal axial motion of the inner tube relative to the outer tube.

Claims

1. A device for delivery of a spinal rod to a bone anchor, the device comprising:

an inner tube having a proximal end, a distal end, and a lumen extending between the proximal end and the distal end, the inner tube having a first slot formed therein, the first slot opening at the distal end of the inner tube and extending toward the proximal end of the inner tube;

an outer tube disposed about at least a portion of the inner tube, the outer tube having a proximal end, a distal end, and a lumen extending between the proximal end and the distal end, the outer tube being sized to span from at least a skin incision in a patient to a predetermined site proximate the spine of the patient, the outer tube having a second slot formed therein, the second slot opening at the distal end of the outer tube and extending toward the proximal end of the outer tube, the distal end of the outer tube being adapted to releasably engage a bone anchor, the inner tube being adjustable relative to the outer tube along the longitudinal axis of the outer tube between a first position and a second position in which the distal end of the inner tube contacts the bone anchor;

a spring positioned within the outer tube and interposed between the inner tube and the outer tube, the spring biasing the inner tube distally; and

a locking member coupled to the outer tube and adjustable relative to the outer tube along the longitudinal axis of the outer tube between a proximal position in which the locking member is spaced apart from the inner tube to permit proximal axial movement of the inner tube relative to the outer tube and a distal position in which the locking member inhibits proximal axial motion of the inner tube relative to the outer tube.

2. The device of claim 1, wherein the spring is interposed between the inner tube and a shoulder provided on an inner surface of the outer tube.

3. The device of claim 1, wherein the spring is positioned about a portion of the inner tube.

4. The device of claim 1, further comprising a washer interposed between the spring and a shoulder provided on an inner surface of the outer tube.

5. The device of claim 1, wherein the inner tube includes a shoulder on an outer surface of the inner tube, the out tube including a shoulder on an inner surface of the outer tube, a distal end of the spring abutting the shoulder on the inner tube and a proximal end of the spring abutting a washer interposed between the spring and the shoulder on the outer tube.

6. The device of claim 1, wherein the distal end of the outer tube includes a plurality of instrument engagement features.

7. The device of claim 6, wherein the plurality of instrument engagement features are a plurality of flat surfaces provided at spaced apart locations on an outer surface of the outer tube.

8. The device of claim 6, wherein the plurality of instrument engagement features are a plurality of openings provided at spaced apart locations on an outer surface of the outer tube.

9. The device of claim 1, wherein the locking member is positioned within the lumen of the outer tube.

10. The device of claim 9, wherein the locking member includes external threads which engage internal threads provided within the outer tube.

11. The device of claim 9, wherein the locking member abuts the proximal end of the inner tube when adjusted to the distal position.

12. The device of claim 9, further comprising a cap positioned on the distal end of the outer tube to inhibit removal of the locking member from within the outer tube.

13. The device of claim 1, wherein the distal end of the outer tube includes a pair of opposed tabs, each tab including an angled surface to facilitate positioning of the tabs about a bone anchor.

14. The device of claim 13, wherein each tab includes a radially inward projection for engaging a connection feature on a bone anchor.

15. The device of claim 14, wherein the spring biases the distal end of the inner tube into abutment with a proximal surface of the radially inward projection of each tab prior to connection with a bone anchor.

16. The device of claim 1, wherein the inner tube includes an annular groove within the lumen of the inner tube to facilitate engagement of an instrument to the inner tube.

17. The device of claim 1, wherein the inner tube includes a retaining slot oriented along the longitudinal axis of the inner tube, the retaining slot receiving a projection from an inner surface of the outer tube.

18. The device of claim 1, wherein the inner tube is removable and replaceable from the outer tube to facilitate cleaning of the inner tube.

19. The device of claim 1, wherein the inner tube includes a pair of adjustable prongs, each prong connected to the inner tube at one end and having a free end at the other end, each prong having a projection at the free end thereof, the prongs being biased to a first position in which the projection is received in an opening in the outer tube and being adjustable to a second position in which the projection is removed from the opening to facilitate removal of the inner tube from the outer tube.

20. The device of claim 1, wherein further comprising a first sliding member connected through an opening in the outer tube to the inner tube to permit adjustment of the inner tube relative to the outer tube.

21. The device of claim 1, further comprising a second sliding member connected through an opening in the outer tube to the inner tube, the second sliding member being positioned opposite the first sliding member.

22. A medical device comprising:

a device for delivery of a spinal rod to a bone anchor comprising

an inner tube having a first slot formed therein, the first slot having an opening at a distal end of the inner tube and extending toward a proximal end of the inner tube,

an outer tube coaxially disposed about at least a portion of the inner tube, the outer tube being sized to span from at least a skin incision in a patient to a predetermined site proximate the spine of the patient, the outer tube having a second slot formed therein aligned with the first slot, the second slot having an opening at a distal end of the outer tube and extending toward a proximal end of the outer tube,

a spring positioned within the outer tube and interposed between the inner tube and the outer tube, the spring biasing the inner tube distally, and

a locking member coupled to the outer tube and adjustable relative to the outer tube along the longitudinal axis of the outer tube between a proximal position in which the locking member is spaced apart from the inner tube to permit proximal axial movement of the inner tube relative to the outer tube and a distal position in which the locking member inhibits proximal axial motion of the inner tube relative to the outer tube; and

a bone anchor comprising a bone anchor having a proximal head and a distal bone engaging portion, and a receiving member having a proximal end having a recess for receiving a spinal connection element, the proximal head of the bone anchor positioned in the receiving member and the distal bone engaging portion extending from the receiving member, wherein the distal end of the outer tube is releasably engaged to the receiving member and the first and second slots are aligned with the recess in the receiving member when the outer tube is releasably engaged to the receiving member.

23. A medical device comprising:

a device for delivery of a spinal rod to a bone anchor comprising

an inner tube having a proximal end, a distal end, and a lumen extending between the proximal end and the distal end,

an outer tube disposed about at least a portion of the inner tube, the outer tube having a proximal end, a distal end, and a lumen extending between the proximal end and the distal end;

the outer tube being sized to span from at least a skin incision in a patient to a predetermined site proximate the spine of the patient,

a spring positioned within the outer tube and interposed between the inner tube and the outer tube, the spring biasing the inner tube distally, and

a locking member coupled to the outer tube and adjustable relative to the outer tube along the longitudinal axis of the outer tube between a proximal position in which the locking member is spaced apart from the inner tube to permit proximal axial movement of the inner tube relative to the outer tube and a distal position in which the locking member inhibits proximal axial motion of the inner tube relative to the outer tube, and

a bone anchor comprising;

a bone anchor having a proximal head and a distal bone engaging portion; and

a receiving member coupled to the bone anchor, the receiving member having a proximal end, a distal end and a recess for receiving a spinal connection element, the proximal end of the receiving member having a pair of arcuate grooves formed on an exterior surface thereof,

wherein the distal end of the outer tube includes a pair of opposed tabs, each tab having a radially inward projection that is sized and shaped to seat within one of the arcuate grooves formed in the receiving member of a bone anchor.

24. A method of delivering a spinal rod to a bone anchor, the method comprising:

advancing the distal end of an outer tube of a device for delivery of a spinal rod to a bone anchor over a proximal end of a receiving member of a bone anchor,

engaging the distal end of an inner tube of the device with the proximal end of the receiving member, the inner tube moving proximally relative to the outer tube during advancing of the outer tube in opposition to a spring force,

connecting the distal end of the outer tube to receiving member of the bone anchor, the spring force maintaining the distal end of the inner tube in engagement with the proximal end of the receiving member of the bone anchor,

adjusting a locking member relative to the inner tube to inhibit proximal movement of the inner tube,

making a minimally invasive stab incision in a patient,

delivering the bone anchor through the incision to proximate a vertebra of the patient,

anchoring the bone anchor in the vertebra,

advancing a spinal rod through the incision and through at least a portion of the device to the bone anchor,

connecting the spinal rod to the bone anchor, and

removing the device from the bone anchor.

25. The method of claim 24, further comprising

connecting a second device for delivery of spinal rod to a bone anchor to a proximal end of a second bone anchor,

making a second minimally invasive stab incision in the patient,

delivering the second bone anchor through the second incision to proximate a second vertebra of the patient,

anchoring the second bone anchor in the second vertebra,

manipulating an end of the spinal rod sub-dermally from proximate the bone anchor to the proximate the second bone anchor,

connecting the spinal rod to the second bone anchor, and

removing the second device from the second bone anchor.

26. The method of claim 24, wherein advancing the spinal rod to the bone anchor include pivoting the spinal rod sub-dermally from a first orientation to a second orientation substantially parallel to the axis of the spine of the patient.

27. The method of claim 24, wherein removing the device from the bone anchor includes adjusting the locking member to permit proximal movement of the inner tube relative to the outer tube.

28. The method of claim 24, wherein adjusting the locking member includes adjusting the locking member distally into engagement with a distal end of the inner tube.

29. The method of claim 28, wherein removing the device from the bone anchor includes adjusting the locking member proximally and moving in the inner tube proximally against the spring force to separate the distal end of the inner tube from the proximal end of the receiving member of the bone anchor.

30. The method of claim 29, wherein moving the inner tube proximally includes connecting an instrument to an annular groove provided within a lumen of the inner tube and moving the inner tube with the instrument.

31. The method of claim 24, further comprising:

removing the inner tube from the outer tube,

cleaning the inner tube and the outer tube,

replacing the inner tube within the outer tube.

32. A system for delivery of a spinal rod to a bone anchor, the system comprising:

an inner tube having a proximal end, a distal end, and a lumen extending between the proximal end and the distal end, the inner tube having a first slot formed therein, the first slot opening at the distal end of the inner tube and extending toward the proximal end of the inner tube, the inner tube having an instrument engagement feature within the lumen of inner tube;

an outer tube disposed about at least a portion of the inner tube, the outer tube having a proximal end, a distal end, and a lumen extending between the proximal end and the distal end, the outer tube being sized to span from at least a skin incision in a patient to a predetermined site proximate the spine of the patient, the outer tube having a second slot formed therein, the second slot opening at the distal end of the outer tube and extending toward the proximal end of the outer tube, the distal end of the outer tube being adapted to releasably engage a bone anchor, the inner tube being adjustable relative to the outer tube along the longitudinal axis of the outer tube between a first position and a second position in which the distal end of the inner tube contacts the bone anchor;

a spring positioned within the outer tube and interposed between the inner tube and the outer tube, the spring biasing the inner tube distally; and

an instrument having a distal end configured to engage the instrument engagement feature of the inner tube to facilitate movement of the inner tube relative to the outer tube.

33. The system of claim 32, wherein the instrument engagement feature is an annular groove.

34. The system of claim 32, wherein the instrument comprises

an inner sleeve,

an outer sleeve positioned about the inner sleeve, a distal end of the inner sleeve extending from a distal end of the outer sleeve and having a projection engageable with the instrument engagement feature of the inner tube of the device.

35. The system of claim 34, wherein the distal end of the inner sleeve comprises a pair of spaced apart prongs, each prong having a projection for engagement with the instrument engagement feature of the inner tube.

36. The system of claim 35, wherein the instrument further comprises a central shaft within the inner sleeve, distal advancement of the central shaft relative to the inner sleeve causing radial deployment of the prongs and the respective projections on the prongs.

37. The system of claim 34, wherein the distal end of the outer sleeve of the instrument includes drive features for adjusting a locking member within the outer tube of the device into and out of engagement with the inner tube.

38. The system of claim 32, wherein the outer tube includes a pair of opposed proximal slots open at the proximal end of the outer tube and extending distally therefrom.

39. The system of claim 38, further comprising a reinforcing instrument positionable within the lumen of the outer tube and having a cross-sectional extent approximately equal to the cross-section extent of the outer tube.