Rod inserter and rod with reduced diameter end

Abstract
An inserter tool for coupling a spinal rod with an implant includes an outer shaft having a proximal end, a distal end and an elongated opening extending between the proximal and distal ends, a handle secured to the proximal end of the outer shaft, and an inner shaft having a proximal end and a distal end, the inner shaft being telescopically received within the elongated opening of the outer shaft and being adapted to move between the proximal and distal ends of the outer shaft. The tool includes a compressible clamping tip secured to the distal end of the inner shaft, the clamping tip including a first section secured to the distal end of the inner shaft, a flexible arm that extends from the first section, and an opening disposed between the first section and the flexible arm. A knob is coupled with the proximal end of the inner shaft, the knob being rotatable in a first direction for extending the clamping tip from the distal end of the outer shaft and in a second direction for retracting the clamping tip into the distal end of the outer shaft so as to compress the flexible arm of the clamping tip toward the first section of the clamping tip.
Description

BRIEF DESCRIPTION OF THE DRAWINGS


FIGS. 1A-1D show a rod inserter tool, in accordance with certain preferred embodiments of the present invention.



FIGS. 2A-2B show a distal end of the rod insertion tool shown in FIG. 1.



FIG. 3 shows another view of the distal end of the rod insertion tool shown in FIGS. 2A-2B.



FIGS. 4A and 4B show a collapsible clamp tip for the rod inserter tool shown in FIGS. 1A-1D, in accordance with certain preferred embodiments of the present invention.



FIGS. 5A and 5B show a collapsible ball socket for the rod inserter tool shown in FIGS. 1A-1D, in accordance with certain preferred embodiments of the present invention.



FIG. 6 shows a kit including a plurality of spinal stabilizing rods, in accordance with certain preferred embodiment of the present invention.



FIG. 7 shows one of the spinal stabilizing rods shown in FIG. 6.



FIG. 8 shows the rod inserter tool of FIGS. 1A-1D holding an end of one of the spinal stabilizing rods shown in FIG. 6.



FIG. 9 shows a spine rod being seated in the heads of pedicle screws, in accordance with certain preferred embodiments of the present invention.



FIG. 10 shows a surgical procedure during which the spinal stabilizing rods of FIGS. 6 and 7 are coupled with the heads of pedicle screws using the rod inserter tool shown in FIGS. 1A-1D, 2A-2B and 3.





DETAILED DESCRIPTION

Referring to FIGS. 1A-1D, in certain preferred embodiments of the present invention, a rod inserter 20 has a proximal end 22 and a distal end 24 remote therefrom. The rod inserter 20 includes an outer shaft 26 having an elongated or longitudinally extending opening that extends from a proximal end 27 to a distal end 28 thereof. The rod inserter 20 also includes an inner shaft 30 (FIG. 1D) that is telescopically received within the outer shaft 26. The rod inserter 20 includes a handle 32 secured to the proximal end 27 of the outer shaft 26. The handle 32 is preferably secured to the outer shaft 26 so that the outer shaft is incapable of moving axially or rotationally relative to the handle 32. The rod inserter 20 also preferably includes a rotatable knob 34 that is rotated in a first direction for moving the inner shaft 30 axially toward the proximal end of the inserter tool and relative to the outer shaft 26, and in a second direction for retracting the inner shaft 30 into the outer shaft 26 and toward the proximal end 22 of the rod inserter 20.


Referring to FIGS. 2A and 2B, the distal end 28 of the outer shaft 26 has an opening 36. As noted above, the opening 36 is preferably an elongated opening that extends toward the proximal end 27 of the outer shaft 26. A collapsible clamp tip 38 is preferably secured to a distal end of the inner shaft 30 and preferably projects from the opening 36 at the distal end 28 of the outer shaft 26. The inner shaft 30 preferably includes a proximal end 39 that is preferably coupled with the rotatable knob 34, as shown in FIG. 1C, and a distal end that is coupled with the collapsible clamp tip 38. As the rotatably knob 34 is rotated, the inner shaft 30 and the collapsible clamp tip 38 preferably move along the axis A1 shown in FIGS. 2A and 2B.


Referring to FIGS. 2A and 3, the collapsible clamp tip 38 also preferably includes a flexible arm 40 that desirably has a hook-like shape. The flexible arm 40 includes a shoulder 42 that is adapted to engage an inner surface of the outer shaft 26. In operation, as the inner shaft 30 is retracted toward the proximal end of the outer shaft 26, the shoulder 42 engages the inner surface of the outer shaft 26 for moving the flexible arm 40 toward a first section 43 of the clamp tip 38, in the direction indicated by the axis A2.


Referring to FIGS. 2A and 3, the collapsible clamp tip 38 includes an opening 44 that is adapted to receive a collapsible ball socket 46 having a slot 48 that enables the collapsible ball socket 46 to be collapsed or compressed.


In certain preferred embodiments of the present invention, the inner shaft 30 is normally urged to project from the distal end 28 of outer shaft 26. The rod inserter 20 may include a spring-like element [not shown] that normally urges the outer shaft 30 into the extended position shown in FIGS. 2A-2B and 3. When it is desired to secure a spinal stabilizing rod using the insertion tool, an end of the rod is passed through the opening in the ball socket 46. The rotatable knob 34 is rotated for retracting the inner shaft 30 and the collapsible clamp tip 38 toward the proximal end 22 of the rod inserter. As the clamp tip 38 is pulled toward the proximal end of the rod inserter, the flexible arm 40 is compressed toward the first section 43 of the clamp tip 38, along the axis A2 as shown in FIGS. 2A and 3. As the flexible arm 40 is compressed toward the first section 43, the collapsible ball socket 46 in the opening 44 of the clamp tip 38 is compressed, which in turn tightens the ball socket 46 about an outer surface of a stabilizing rod.


Referring to FIG. 6, in certain preferred embodiments of the present invention, a kit 50 may include a plurality of stabilizing rods 52A, 52B having different lengths. The stabilizing rods 52 are preferably used for stabilizing different sections of a spinal segment. The stabilizing rods 52 desirably have a curvature that generally matches the curvature normally found in a particular spinal segment. Thus, stabilizing rods having different lengths and/or curvatures may be provided. The kit 50 preferably includes a holder 54 having a plurality of openings 56 for holding the spinal rods 52.


Referring to FIG. 7, in one preferred embodiment of the present invention, a spinal stabilizing rod 52 has an elongated shaft 58 that extends between a first end 60 and a second end 62. The elongated shaft 58 preferably has an outer surface that may have a generally cylindrical shape. As shown in FIG. 7, the first and second ends 60, 62 of the elongated shaft 58 have reduced diameter sections. The collapsible ball socket 46 shown in FIG. 3 preferably fits over the reduced diameter ends 60, 62 of the spinal rod 52. The reduced diameter or tapered ends 60, 62 preferably allow for easy attachment of the ball socket 46 over the ends of the stabilizing rod.


As shown in FIG. 7, the reduced diameter ends 60, 62 have curved surfaces. In certain preferred embodiments, the reduced diameter ends have a spherical shape. The spherical shape and/or reduced diameter ends desirably enable easier movement of the rods through the tissue during a surgical procedure. In addition, the reduced diameter ends 60, 62 enable the distal end 24 of the insertion tool 20 (FIG. 1A) to be made smaller.


Although the particular embodiment shown in FIGS. 6 and 7 show stabilizing rods having reduced diameter ends, in other preferred embodiments of the present invention, it is contemplated that conventional stabilizing rods having a constant diameter along the length thereof may be used in conjunction with the tools shown and described herein.


In certain preferred embodiments, one or more stabilizing rods 52 may include an alignment marking 64 that may be used by a surgeon for orienting the stabilizing rod. As is evident in FIGS. 6 and 7, some stabilizing rods may have a curvature. The alignment markings 64 may be used by a surgeon to properly orient the rod so that the surgeon may identify the axis upon which the stabilizing rod curves. In the particular embodiment shown in FIG. 7, the alignment marking 64 is provided at the first end 60 of the stabilizing rod 52. In other preferred embodiments, however, the alignment marking 64 may extend along the length of the stabilizing rod, may be provided at both the first and second ends of the stabilizing rod, or may be provided intermittently along the length of the stabilizing rod. In still other preferred embodiments, a series of alignment markings may be provided around the outer surface of the stabilizing rod. In these particular preferred embodiments, a first marking may indicate that the opposite end of the rod is curving toward the surgeon and a second marking may indicate that the opposite end of the rod is curving away from the surgeon. The alignment marking 64 is preferably used by the surgeon for identifying the curvature of the spinal rod. In instances where the surgeon has to release an end of the spinal rod from the collapsible ball socket for repositioning the rod inserter relative to the spinal rod, the alignment marking 64 may be used after the rod has been re-secured by the clamping tip of the rod inserter.



FIGS. 8-10 show the rod inserter 20 and stabilizing rods described above during spinal surgery. Referring to FIGS. 8 and 9, after pedicle screws 70 have been anchored in vertebral bone, a first rod inserter 120 is used for securing a spinal rod 152 and seating the spinal rod in the heads 72 of the pedicle screws. The ball socket 146 at the distal end 124 of the rod inserter 120 engages a reduced diameter end of the stabilizing rod 152. As shown in FIG. 8, the stabilizing rod 152 has a curvature. The alignment marking shown in FIG. 7 may be used for properly orienting the stabilizing rod as it is inserted into the heads 72 of the pedicle screws 70 shown in FIG. 9. When inserting the stabilizing rod, the surgeon may need to reposition to ball socket relative to the end of the stabilizing rod to improve the insertion technique and/or obtain better leverage for inserting the stabilizing rod. In order to reposition the clamping tip over the end 160 of the stabilizing rod 152, the rotatable knob 134 may be rotated for loosening the clamping tip relative to the end of the stabilizing rod. Once the clamping tip has been properly repositioned over the end of the stabilizing rod, the rotatable knob may be tightened for once again clamping the clamping tip and the compressible ball over the end of the rod.


During a surgical procedure, more than one rod inserter may be used. Referring to FIG. 10, a second rod inserter 220 has a distal end 224 that is secured to a reduced diameter end 260 of a second spinal stabilizing rod 252.


Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims.

Claims
  • 1. An inserter tool for coupling a spinal rod with an implant comprising: an outer shaft having a proximal end, a distal end and an elongated opening extending between the proximal and distal ends;a handle secured to the proximal end of said outer shaft;an inner shaft having a proximal end and a distal end, said inner shaft being telescopically received within the elongated opening of said outer shaft and being adapted to move between the proximal and distal ends of said outer shaft;a compressible clamping tip secured to the distal end of said inner shaft, said clamping tip including a first section secured to the distal end of said inner shaft, a flexible arm that extends from the first section, and an opening disposed between the first section and the flexible arm;a knob coupled with the proximal end of said inner shaft, said knob being rotatable in a first direction for extending said clamping tip from the distal end of said outer shaft and in a second direction for retracting said clamping tip into the distal end of said outer shaft so as to compress the flexible arm of said clamping tip toward the first section of said clamping tip.
  • 2. The inserter tool as claimed in claim 1, further comprising a socket disposed in the opening of said clamping tip, said socket having a slot that enables said socket to be compressed.
  • 3. The inserter tool as claimed in claim 2, wherein said socket is a ball socket having an aperture adapted to receive a stabilizing rod.
  • 4. The inserter tool as claimed in claim 3, wherein the opening of said clamping tip defines an inner surface and said ball socket has an outer surface with a plurality of notches formed therein that are adapted to engage the inner surface of the opening.
  • 5. The tool as claimed in claim 1, wherein said inner shaft extends through said handle for being attached to said knob.
  • 6. The tool as claimed in claim 5, wherein the proximal end of said inner shaft has threads and said knob has a female opening with internal threads that are adapted to receive the threads of said inner shaft.
  • 7. The tool as claimed in claim 1, wherein said clamping tip has a hook shape and the flexible arm of said clamping tip has a shoulder that is engageable with the distal end of said outer shaft when said inner shaft is retracted relative to said outer shaft.
  • 8. The tool as claimed in claim 7, wherein the flexible arm of said clamping tip is connected with the first section of said clamping tip through a flexible intermediate section.
  • 9. The tool as claimed in claim 8, wherein the flexible intermediate section has a curved surface that extends between the first section of said clamping tip and the flexible arm of said clamping tip.
  • 10. The tool as claimed in claim 1, further comprising said stabilizing rod being secured by said clamping tip.
  • 11. The tool as claimed in claim 10, wherein said stabilizing rod has at least one end with a reduced diameter and said clamping tip is engageable with the reduced diameter end.
  • 12. The tool as claimed in claim 11, wherein the reduced diameter end has a spherical surface.
  • 13. The tool as claimed in claim 1, wherein said handle has a roughened surface.
  • 14. An inserter tool comprising: an outer shaft having a proximal end, a distal end and an elongated opening extending between the proximal and distal ends;a handle secured to the proximal end of said outer shaft;an inner shaft telescopically received within the elongated opening of said outer shaft and being adapted to move between proximal and distal ends of said outer shaft;a clamping tip secured to a distal end of said inner shaft, said clamping tip including a first section secured to the distal end of said inner shaft, a flexible arm that extends from the first section, and an opening disposed between the first section of said clamping tip and the flexible arm of said clamping tip;a knob coupled with a proximal end of said inner shaft, said knob being rotatable in a first direction for extending said clamping tip from the distal end of said outer shaft and in a second direction for retracting said clamping tip into the elongated opening at the distal end of said outer shaft so as to compress the flexible arm of said clamping tip toward the first section of said clamping tip.
  • 15. The tool as claimed in claim 14, further comprising a stabilizing rod being securable by said clamping tip.
  • 16. The tool as claimed in claim 15, wherein said stabilizing rod has first and second ends with at least one of the first and second ends having a reduced diameter relative to a remainder of said stabilizing rod.
  • 17. The tool as claimed in claim 16, wherein the reduced diameter end of said stabilizing rod has a spherical surface.
  • 18. A pedicle screw assembly comprising: a bone fastener having a lower end for engaging bone and an upper end remote from the lower end;a head having a rod-receiving channel attached to the upper end of said bone fastener;a spinal rod insertable into the rod-receiving channel of said head, said spinal rod having an outer surface extending between first and second ends thereof, wherein at least one of the first and second ends has a reduced diameter section.
  • 19. The assembly as claimed in claim 18, wherein both of the first and second ends of said spinal rod have reduced diameter sections.
  • 20. The assembly as claimed in claim 19, wherein the outer surface of said spinal rod has a first diameter and the reduced diameter first and second ends of said spinal rod have second diameters that are smaller than the first diameter.
  • 21. The assembly as claimed in claim 18, wherein the at least one of the first and second ends of said spinal rod has a spherical surface.
  • 22. The assembly as claimed in claim 19, wherein the first and second ends of said spinal rod have a spherical surface.
  • 23. The assembly as claimed in claim 18, wherein said spinal rod is curved between the first and second ends thereof and the outer surface of said spinal rod has at least one alignment marker for identifying an axis of curvature of said spinal rod.
  • 24. The assembly as claimed in claim 23, wherein the at least one alignment marker is a line that extends along the axis of curvature of said spinal rod.
  • 25. A spinal rod having an outer surface extending between a first end and a second end thereof, wherein the outer surface of said spinal rod has a reduced diameter section at at least one of the first and second ends.
  • 26. The spinal rod as claimed in claim 25, wherein said spinal rod has reduced diameter sections at both the first and second ends thereof.
  • 27. The spinal rod as claimed in claim 25, wherein the reduced diameter section comprises a spherical surface.
  • 28. The spinal rod as claimed in claim 25, wherein said spinal rod is curved between the first and second ends thereof.
  • 29. The spinal rod as claimed in claim 28, wherein the outer surface of said spinal rod has at least one alignment marker for identifying an axis of curvature of said spinal rod.
  • 30. The spinal rod as claimed in claim 26, wherein the reduced diameter sections have spherical surfaces and the outer surface of said spinal rod extending between the reduced diameter sections has a cylindrical surface.
CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit of U.S. Provisional Application Ser. No. 60/847,009, filed Sep. 25, 2006, the disclosure of which is hereby incorporated by reference herein. The present application is related to U.S. patent application Ser. No. 11/526,785, entitled, “Rod Contouring Apparatus and Method for Percutaneous Pedicle Screw Extension,” filed Sep. 25, 2006, which claims the benefit of U.S. Provisional Application No. 60/765,606, filed Feb. 6, 2006, the disclosures of which are hereby incorporated by reference herein.

Provisional Applications (1)
Number Date Country
60847009 Sep 2006 US