Extension for use with stabilization systems for internal structures
View Patent ↗An extension for use in a procedure to implant a stabilization system for bony structures such as vertebrae is described. The extension is formed by a tubular body with an engagement mechanism at one end to removably engage with a poly-axial head of a bone anchor assembly. A locking ring working with a slide are used to temporarily lock the poly-axial head and extension in the desired relationship for performing the procedure. The locking ring includes a slot in which resides a pin on the slider. Twisting the locking ring causes the pin to move in the slot and thereby move the slider either up or down. In one position a locking body on the slider engages with the poly-axial assembly locking the extension in place. In the other position, the locking body is disengaged from the poly-axial head allowing the extension to be decoupled from the bone anchor assembly.
1. A surgical system comprising:
a bone anchor comprising:
a head, wherein the head includes at least one circumferential key; and
a first torqueing surface disposed on the at least one circumferential key; and
an extension for use in the surgical system, the extension comprising:
an elongated structure having a central bore, the elongated structure having a proximal portion and a distal portion; and a longitudinal passage;
an actuating ring disposed around the central bore, wherein the actuating ring has a helical slot disposed within the actuating ring;
a slider slideably coupled to the longitudinal passage and coupled to the actuating ring wherein the slider is selectively positionable between a first position and a second position;
at least one interior channel disposed on the interior surface of the central bore at the distal portion adapted to mate with the circumferential key, where the at least one interior channel has a second torquing surface for transmitting torque to the bone anchor head; and
a proximal head portion coupled to the actuating ring wherein the proximal head portion has a plurality of torque flats adapted to couple to a torque transmission instrument.
2. The extension of claim 1 , wherein the slider has a pin positioned near a proximal end of the slider, the pin dimensioned to couple to the helical slot, such that as the actuating ring is rotated the slider moves longitudinally within the longitudinal passage from the first position to the second position.
3. The extension of claim 2 wherein the slider has a locking protrusion coupled to a distal portion adapted to mate with a longitudinal groove on a bone anchor head.
4. The extension of claim 1 wherein the proximal head portion has at least one protuberance adapted to mate with at least one slot in a proximal face of the actuating ring.
5. The extension of claim 4 further comprising a biasing mechanism disposed around the bore to bias the at least one protuberance to the slot.
6. The extension of claim 5 further comprising a torque key coupled to the proximal head portion and the actuating ring.
7. The extension of claim 1 wherein the longitudinal passage is a longitudinal slot on the exterior surface of the elongated structure and the longitudinal slot has a dovetail cross-sectional shape.
8. The extension of claim 1 wherein the distal portion has a least one opening dimensioned to allow longitudinal passage of the circumferential key such that the circumferential key may be aligned and inserted into the at least one interior channel.
9. An extension for use in a surgical system, the extension comprising:
a tubular body comprising:
an engagement mechanism at a distal end for connecting to a bone anchor head; and
a longitudinal passage;
a locking ring connected to a proximal end of said tubular body and including a helical slot disposed around a portion of a circumference of said locking ring, said slot having a first end and a second end;
a slider slideably coupled to said longitudinal passage and coupled to said locking ring at a proximal portion of the slider;
a locking body coupled to a distal portion of said slider for engaging said bone anchor head to prevent movement of said bone anchor head in relation to said extension when said locking ring is turned such that a pin is at said first end of said slot; and
wherein said engagement mechanism at said distal end of said tubular body includes at least one twist mechanism for controllably engaging with a respective twist mechanism on said bone anchor head.
10. The extension of claim 9 further comprising an anti-torque mechanism connected to said proximal end of said tubular body proximal to said locking ring.
11. The extension of claim 9 wherein instruments are inserted through said extension to interact with a connector connected to said bone anchor head, said connector extending into an interior of said extension.
12. The extension of claim 9 wherein instruments are inserted through said extension to interact with a bone anchor connected to said bone anchor head.
13. The extension of claim 9 further comprising:
at least one opening along said tubular body for allowing a proximal end of a connector which connector has a distal end rotatably captured by said bone anchor head to be rotated out of said extension through said opening.
14. The extension of claim 9 further comprising:
at least one opening along said tubular body for allowing entry of an end of a connector allowing said bone anchor head to capture the end of said connector.
15. The extension of claim 9 wherein said locking body is disengaged from said bone anchor head by twisting the locking ring to move said pin to said second end of said slot.
16. The extension of claim 9 wherein said slider is in a groove formed in said tubular body.
17. An extension for use in a surgical system, the extension comprising:
an elongated structure having a central bore, the elongated structure having a proximal portion and a distal portion, and a longitudinal passage;
wherein the longitudinal passage is a longitudinal slot on an exterior surface of the elongated structure and the longitudinal slot has a dovetail cross-sectional shape;
an actuating ring disposed around the central bore;
a slider slideably coupled to the longitudinal passage and coupled to the actuating ring wherein the slider is selectively positionable between a first position and a second position; and
at least one interior channel disposed on an interior surface of the central bore at the distal portion adapted to mate with a circumferential key of a bone anchor head, where the at least one interior channel has a torquing surface for transmitting torque to the bone anchor head.
18. The extension of claim 17 , wherein the actuating ring has a helical slot disposed within the actuating ring.
19. The extension of claim 18 , wherein the slider has a pin positioned near a proximal end of the slider, the pin dimensioned to couple to the helical slot, such that as the actuating ring is rotated the slider moves longitudinally within the longitudinal passage from the first position to the second position.
20. The extension of claim 19 wherein the slider has a locking protrusion coupled to the distal portion adapted to mate with a longitudinal groove on a bone anchor head.
21. The extension of claim 17 , further comprising a proximal head portion coupled to the actuating ring wherein the proximal head portion has a plurality of torque flats adapted to couple to a torque transmission instrument.
22. The extension of claim 21 wherein the proximal head portion has at least one protuberance adapted to mate with at least one slot in a proximal face of the actuating ring.
23. The extension of claim 22 further comprising a biasing mechanism disposed around the bore to bias the at least one protuberance to the slot.
24. The extension of claim 23 further comprising a torque key coupled to the proximal head portion and the actuating ring.
25. The extension of claim 17 wherein the distal portion has a least one opening dimensioned to allow longitudinal passage of the circumferential key such that the circumferential key may be aligned and inserted into the at least one interior channel.
26. A surgical system comprising:
a bone anchor comprising:
a head, wherein the head includes at least one circumferential key; and
a first torquing surface disposed on the at least one circumferential key; and
an extension for use in the surgical system, the extension comprising:
an elongated structure having a central bore, the elongated structure having a proximal portion and a distal portion; and a longitudinal passage; wherein the longitudinal passage is a longitudinal slot on an exterior surface of the elongated structure and the longitudinal slot has a dovetail cross-sectional shape;
an actuating ring disposed around the central bore wherein the actuating ring has a helical slot disposed within the actuating ring;
a slider slideably coupled to the longitudinal passage and coupled to the actuating ring wherein the slider is selectively positionable between a first position and a second position; and
at least one interior channel disposed on the interior surface of the central bore at the distal portion adapted to mate with the circumferential key, where the at least one interior channel has a second torquing surface for transmitting torque to the bone anchor head.
27. The extension of claim 26 , wherein the slider has a pin positioned near a proximal end of the slider, the pin dimensioned to couple to the helical slot, such that as the actuating ring is rotated the slider moves longitudinally within the longitudinal passage from the first position to the second position.
28. The extension of claim 27 wherein the slider has a locking protrusion coupled to a distal portion adapted to mate with a longitudinal groove on a bone anchor head.
29. The extension of claim 26 , further comprising a proximal head portion coupled to the actuating ring wherein the proximal head portion has a plurality of torque flats to couple to a torque transmission instrument.
30. The extension of claim 29 wherein the proximal head portion has at least one protuberance adapted to mate with at least one slot in a proximal face of the actuating ring.
31. The extension of claim 30 further comprising a biasing mechanism disposed around the bore to bias the at least one protuberance to the slot.
32. The extension of claim 31 further comprising a torque key coupled to the proximal head portion and the actuating ring.
33. The extension of claim 26 wherein the distal portion has a least one opening dimensioned to allow longitudinal passage of the circumferential key such that the circumferential key may be aligned and inserted into the at least one interior channel.
34. An extension for use in a surgical system, the extension comprising:
an elongated structure having a central bore, the elongated structure having a proximal portion and a distal portion, and a longitudinal passage;
wherein the longitudinal passage is a longitudinal slot on the exterior surface of the elongated structure and the longitudinal slot has a dovetail cross-sectional shape;
an actuating ring disposed around the central bore;
a slider slideably coupled to the longitudinal passage and coupled to the actuating ring wherein the slider is selectively positionable between a first position and a second position;
at least one interior channel disposed on an interior surface of the central bore at the distal portion adapted to mate with a circumferential key of a bone anchor head, where the at least one interior channel has a torquing surface for transmitting torque to the bone anchor head; and
a proximal head portion coupled to the actuating ring wherein the proximal head portion has a plurality of torque flats adapted to couple to a torque transmission instrument.
35. The extension of claim 34 , wherein the actuating ring has a helical slot disposed within the actuating ring.
36. The extension of claim 35 , wherein the slider has a pin positioned near a proximal end of the slider, the pin dimensioned to couple to the helical slot, such that as the actuating ring is rotated the slider moves longitudinally within the longitudinal passage from the first position to the second position.
37. The extension of claim 36 wherein the slider has a locking protrusion coupled to the distal portion adapted to mate with a longitudinal groove on a bone anchor head.
38. The extension of claim 37 wherein the proximal head portion has at least one protuberance adapted to mate with at least one slot in a proximal face of the actuating ring, wherein the extension further comprises a biasing mechanism disposed around the bore to bias the at least one protuberance to the slot.
39. The extension of claim 38 further comprising a torque key coupled to the proximal head portion and the actuating ring.
40. The extension of claim 34 wherein the distal portion has a least one opening dimensioned to allow longitudinal passage of the circumferential key such that the circumferential key may be aligned and inserted into the at least one interior channel.
41. A surgical system comprising:
a bone anchor comprising:
a head, wherein the head includes at least one circumferential key; and
a first torqueing surface disposed on the at least one circumferential key; and
an extension for use in the surgical system, the extension comprising:
an elongated structure having a central bore, the elongated structure having a proximal portion and a distal portion; and a longitudinal passage;
an actuating ring disposed around the central bore;
a slider slideably coupled to the longitudinal passage and coupled to the actuating ring wherein the slider is selectively positionable between a first position and a second position;
at least one interior channel disposed on the interior surface of the central bore at the distal portion adapted to mate with the circumferential key, where the at least one interior channel has a second torquing surface for transmitting torque to the bone anchor head; and
a proximal head portion coupled to the actuating ring wherein the proximal head portion has a plurality of torque flats adapted to couple to a torque transmission instrument; and wherein the proximal head portion has at least one protuberance adapted to mate with at least one slot in a proximal face of the actuating ring.
42. The extension of claim 41 , wherein the actuating ring has a helical slot disposed within the actuating ring.
43. The extension of claim 42 , wherein the slider has a pin positioned near a proximal end of the slider, the pin dimensioned to couple to the helical slot, such that as the actuating ring is rotated the slider moves longitudinally within the longitudinal passage from the first position to the second position.
44. The extension of claim 43 wherein the slider has a locking protrusion coupled to a distal portion adapted to mate with a longitudinal groove on a bone anchor head.
45. The extension of claim 41 further comprising a biasing mechanism disposed around the bore to bias the at least one protuberance to the slot.
46. The extension of claim 45 further comprising a torque key coupled to the proximal head portion and the actuating ring.
47. The extension of claim 41 wherein the longitudinal passage is a longitudinal slot on the exterior surface of the elongated structure and the longitudinal slot has a dovetail cross-sectional shape.
48. The extension of claim 41 wherein the distal portion has a least one opening dimensioned to allow longitudinal passage of the circumferential key such that the circumferential key may be aligned and inserted into the at least one interior channel.
49. A surgical system comprising:
a bone anchor comprising:
a head, wherein the head includes at least one circumferential key; and
a first torqueing surface disposed on the at least one circumferential key; and
an extension for use in the surgical system, the extension comprising:
an elongated structure having a central bore, the elongated structure having a proximal portion and a distal portion; and a longitudinal passage, wherein the longitudinal passage is a longitudinal slot on the exterior surface of the elongated structure and the longitudinal slot has a dovetail cross-sectional shape;
an actuating ring disposed around the central bore;
a slider slideably coupled to the longitudinal passage and coupled to the actuating ring wherein the slider is selectively positionable between a first position and a second position;
at least one interior channel disposed on the interior surface of the central bore at the distal portion adapted to mate with the circumferential key, where the at least one interior channel has a second torquing surface for transmitting torque to the bone anchor head; and
a proximal head portion coupled to the actuating ring wherein the proximal head portion has a plurality of torque flats adapted to couple to a torque transmission instrument.
50. The extension of claim 49 , wherein the actuating ring has a helical slot disposed within the actuating ring.
51. The extension of claim 50 , wherein the slider has a pin positioned near a proximal end of the slider, the pin dimensioned to couple to the helical slot, such that as the actuating ring is rotated the slider moves longitudinally within the longitudinal passage from the first position to the second position.
52. The extension of claim 51 wherein the slider has a locking protrusion coupled to a distal portion adapted to mate with a longitudinal groove on a bone anchor head.
53. The extension of claim 49 wherein the proximal head portion has at least one protuberance adapted to mate with at least one slot in a proximal face of the actuating ring.
54. The extension of claim 53 further comprising a biasing mechanism disposed around the bore to bias the at least one protuberance to the slot.
55. The extension of claim 54 further comprising a torque key coupled to the proximal head portion and the actuating ring.
56. The extension of claim 49 wherein the distal portion has a least one opening dimensioned to allow longitudinal passage of the circumferential key such that the circumferential key may be aligned and inserted into the at least one interior channel.
57. An extension for use in a surgical system, the extension comprising:
an elongated structure having a central bore, the elongated structure having a proximal portion and a distal portion, and a longitudinal passage; wherein the longitudinal passage is a longitudinal slot on the exterior surface of the elongated structure and the longitudinal slot has a dovetail cross-sectional shape;
an actuating ring disposed around the central bore;
a slider slideably coupled to the longitudinal passage and coupled to the actuating ring wherein the slider is selectively positionable between a first position and a second position;
at least one interior channel disposed on an interior surface of the central bore at the distal portion adapted to mate with a circumferential key of a bone anchor head, where the at least one interior channel has a torquing surface for transmitting torque to the bone anchor head; and
wherein the distal portion has at least one opening dimensioned to allow longitudinal passage of the circumferential key such that the circumferential key may be aligned and inserted into the at least one interior channel.
58. The extension of claim 57 , wherein the actuating ring has a helical slot disposed within the actuating ring.
59. The extension of claim 58 , wherein the slider has a pin positioned near a proximal end of the slider, the pin dimensioned to couple to the helical slot, such that as the actuating ring is rotated the slider moves longitudinally within the longitudinal passage from the first position to the second position.
60. The extension of claim 59 wherein the slider has a locking protrusion coupled to the distal portion adapted to mate with a longitudinal groove on a bone anchor head.
61. The extension of claim 60 further comprising a proximal head portion coupled to the actuating ring wherein the proximal head portion has at least one protuberance adapted to mate with at least one slot in a proximal face of the actuating ring.
62. The extension of claim 61 further comprising a biasing mechanism disposed around the bore to bias the at least one protuberance to the slot.
63. The extension of claim 62 further comprising a torque key coupled to the proximal head portion and the actuating ring.
64. A surgical system comprising:
a bone anchor comprising:
a head, wherein the head includes at least one circumferential key; and
a first torquing surface disposed on the at least one circumferential key; and
an extension for use in the surgical system, the extension comprising:
an elongated structure having a central bore, the elongated structure having a proximal portion and a distal portion; and a longitudinal passage; wherein the longitudinal passage is a longitudinal slot on an exterior surface of the elongated structure and the longitudinal slot has a dovetail cross-sectional shape;
an actuating ring disposed around the central bore;
a slider slideably coupled to the longitudinal passage and coupled to the actuating ring wherein the slider is selectively positionable between a first position and a second position;
at least one interior channel disposed on the interior surface of the central bore at the distal portion adapted to mate with the circumferential key, where the at least one interior channel has a second torquing surface for transmitting torque to the bone anchor head; and
a proximal head portion coupled to the actuating ring wherein the proximal head portion has a plurality of torque flats to couple to a torque transmission instrument.
65. The extension of claim 64 , wherein the actuating ring has a helical slot disposed within the actuating ring.
66. The extension of claim 65 , wherein the slider has a pin positioned near a proximal end of the slider, the pin dimensioned to couple to the helical slot, such that as the actuating ring is rotated the slider moves longitudinally within the longitudinal passage from the first position to the second position.
67. The extension of claim 66 wherein the slider has a locking protrusion coupled to a distal portion adapted to mate with a longitudinal groove on a bone anchor head.
68. The extension of claim 67 wherein the proximal head portion has at least one protuberance adapted to mate with at least one slot in a proximal face of the actuating ring, wherein the proximal head further comprises a biasing mechanism disposed around the bore to bias the at least one protuberance to the slot.
69. The extension of claim 68 further comprising a torque key coupled to the proximal head portion and the actuating ring.
70. The extension of claim 64 wherein the distal portion has a least one opening dimensioned to allow longitudinal passage of the circumferential key such that the circumferential key may be aligned and inserted into the at least one interior channel.
71. A surgical system comprising:
a bone anchor comprising:
a head, wherein the head includes at least one circumferential key; and
a first torquing surface disposed on the at least one circumferential key; and an extension for use in the surgical system, the extension comprising:
an elongated structure having a central bore, the elongated structure having a proximal portion and a distal portion; and a longitudinal passage; wherein the longitudinal passage is a longitudinal slot on an exterior surface of the elongated structure and the longitudinal slot has a dovetail cross-sectional shape; wherein the distal portion has a least one opening dimensioned to allow longitudinal passage of the circumferential key such that the circumferential key may be aligned and inserted into the at least one interior channel,
an actuating ring disposed around the central bore;
a slider slideably coupled to the longitudinal passage and coupled to the actuating ring wherein the slider is selectively positionable between a first position and a second position; and
at least one interior channel disposed on the interior surface of the central bore at the distal portion adapted to mate with the circumferential key, where the at least one interior channel has a second torquing surface for transmitting torque to the bone anchor head.
72. The extension of claim 71 , wherein the actuating ring has a helical slot disposed within the actuating ring.
73. The extension of claim 72 , wherein the slider has a pin positioned near a proximal end of the slider, the pin dimensioned to couple to the helical slot, such that as the actuating ring is rotated the slider moves longitudinally within the longitudinal passage from the first position to the second position.
74. The extension of claim 73 wherein the slider has a locking protrusion coupled to a distal portion adapted to mate with a longitudinal groove on a bone anchor head.
75. The extension of claim 74 further comprising a proximal head portion coupled to the actuating ring wherein the proximal head portion has at least one protuberance adapted to mate with at least one slot in a proximal face of the actuating ring.
76. The extension of claim 75 further comprising a biasing mechanism disposed around the bore to bias the at least one protuberance to the slot.
77. The extension of claim 76 further comprising a torque key coupled to the proximal head portion and the actuating ring.