REDUCTION SLEEVE

• US 20080051794A1
• Filed: 08/07/2007
• Published: 02/28/2008
• Est. Priority Date: 08/22/2006
• Status: Active Grant

• Current Assignee: Depuy Synthes Products Incorporated (Johnson & Johnson)
• Original Assignee: DePuy Synthes Products LLC (Johnson & Johnson)
• Inventors: Rathbun, David S., Dec, Brian
• Granted Patent: US 8,663,292 B2
• Time in Patent Office: Days
• US Class Current: 606/73
• CPC Class Codes: A61B 17/7032 Screws or hooks with U-shaped head or back through which longitudinal rods pass
• CPC Class Codes: A61B 17/7074 Tools specially adapted for spinal fixation operations other than for bone removal or filler handling A61B17/7062, A61B17/808, A61B17/8858 take precedence; for spinal image producing devices A61B90/36, A61B34/20; markers A61B90/39
• 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
• CPC Class Codes: A61B 17/7091 for applying, tightening or removing longitudinal element-to-bone anchor locking elements, e.g. caps, set screws, nuts or wedges
• CPC Class Codes: A61B 2017/567 Joint mechanisms or joint supports in addition to the natural joints and outside the joint gaps

Abstract

A reduction sleeve for facilitating insertion of a spinal rod into a rod-receiving channel formed in a bone fixation element. The reduction sleeve may include a through-bore sized and configured to receive the bone fixation element and a substantially transverse channel sized and configured to receive the spinal rod. The channel being substantially aligned with the rod-receiving channel formed in the bone fixation element so that, once the bone fixation element has been inserted into the reduction sleeve, the spinal rod can pass through the aligned channels. The reduction sleeve may also include at least one break-off point or region for facilitating breaking and removal of the reduction sleeve once the spinal rod has been clamped into the rod-receiving channel of the bone fixation element. The reduction sleeve may also include a plurality of threads formed thereon for engaging a reduction instrument, an alignment mechanism so that the bone fixation element can only be inserted into the reduction sleeve when the rod-receiving channels are aligned, and an inwardly projecting protrusion formed on the inner surface of the reduction sleeve so that, once inserted, the projection contacts a top surface formed on the bone fixation element.

Claims

1. A reduction sleeve for facilitating insertion of a longitudinal spinal rod into a bone fixation element, the bone fixation element including a bone anchor and a head portion having a rod-receiving channel formed therein for receiving the spinal rod, the reduction sleeve comprising:

a longitudinal axis, an upper end, a lower end, an outer surface, a channel, and a through-bore extending from the upper end to the lower end, the through bore defining an inner surface;

wherein the through-bore is substantially perpendicular to the longitudinal axis and the through-bore is sized and configured to receive the bone fixation element; and

wherein the channel is substantially transverse to the longitudinal axis and the channel is substantially aligned with the rod-receiving channel formed in the bone fixation element so that, once the bone fixation element has been inserted into the reduction sleeve, the spinal rod can pass through the channel formed in the reduction sleeve and the rod-receiving channel formed in the bone fixation element;

the reduction sleeve further comprising at least one break-off point or region for facilitating breaking the reduction sleeve into multiple pieces.

2. The reduction sleeve of claim 1, wherein the reduction sleeve includes a pair of break-off points or regions formed in the lower end of the reduction sleeve beneath the channel formed in the reduction sleeve.

3. The reduction sleeve of claim 1, wherein the channel formed in the reduction sleeve defines a pair of spaced apart arms joined by a bridge member so that the reduction sleeve is generally in the form of a U-shaped member, the break-off point or region being formed in the bridge member.

4. The reduction sleeve of claim 1, wherein the break-off point or region is formed beneath the channel and extends vertically from the channel to the lower end of the reduction sleeve.

5. The reduction sleeve of claim 1, wherein the rod-receiving channel formed in the bone fixation element defines a pair of spaced apart arms and the channel formed in the reduction sleeve defines a pair of spaced apart arms, the spaced apart arms being substantially aligned with one another once the bone fixation element has been inserted into the reduction sleeve.

6. The reduction sleeve of claim 1, wherein the reduction sleeve further comprises a plurality of threads for engaging a reduction instrument.

7. The reduction sleeve of claim 6, wherein the plurality of threads are formed on the outer surface of the reduction sleeve.

8. The reduction sleeve of claim 1, wherein the lower end of the reduction sleeve includes a tapered surface sized and configured to receive a correspondingly tapered surface formed on the bone fixation element.

9. The reduction sleeve of claim 1, wherein, once inserted, the bone anchor extends through the lower end of the reduction sleeve such that the bone anchor may be moveable with respect to the bone fixation element and with respect to the reduction sleeve.

10. The reduction sleeve of claim 1, wherein the reduction sleeve includes an alignment mechanism so that the bone fixation element can only be inserted into the reduction sleeve when the rod-receiving channel formed in the bone fixation element is aligned with the channel formed in the reduction sleeve.

11. The reduction sleeve of claim 10, wherein the alignment mechanism is an alignment flat formed in the lower end of the reduction sleeve, the alignment flat being sized and configured to contact a corresponding flat formed on the bone fixation element.

12. The reduction sleeve of claim 1, wherein the reduction sleeve further comprises a protrusion formed on the inner surface of the reduction sleeve, the protrusion projecting inward from the inner surface so that, once inserted, the projection contacts a top surface formed on the bone fixation element.

13. The reduction sleeve of claim 12, wherein, once inserted, the bone fixation element is secured within the reduction sleeve in-between the lower end of the reduction sleeve and the protrusion.

14. The reduction sleeve of claim 1, wherein the bone anchor is sized and configured to engage a patient'"'"'s vertebra.

15. The reduction sleeve of claim 1, wherein the reduction sleeve is in the shape of a sleeve or tubular member.

16. The reduction sleeve of claim 1, wherein the transverse channel extends from the upper end towards the lower end.

17. A reduction sleeve for facilitating insertion of a longitudinal spinal rod into a bone fixation element, the bone fixation element including a bone anchor and a head portion having a rod-receiving channel formed therein for receiving the spinal rod, the rod-receiving channel defining a pair of spaced apart arms having a top surface, the reduction sleeve comprising:

a longitudinal axis, an upper end, a lower end, an outer surface, a channel, and a through-bore extending from the upper end to the lower end, the through-bore defining an inner surface;

wherein the through-bore is substantially perpendicular to the longitudinal axis and the through-bore is sized and configured to receive the bone fixation element; and

wherein the channel is substantially transverse to the longitudinal axis and the channel defines a pair of spaced apart arms having a top surface; and

wherein the top surface of the spaced apart arms formed in the reduction sleeve are sized and configured to extend above the top surface formed in the bone fixation element by a distance A, when the bone fixation element is inserted into the reduction sleeve; and

wherein the reduction sleeve further comprises at least one break-off point or region for facilitating breaking the reduction sleeve into multiple pieces.

18. The reduction sleeve of claim 17, wherein the spaced apart arms formed in the reduction sleeve are sized and configured to substantially align with the pair of spaced apart arms formed in the bone fixation element, when the bone fixation element is inserted into the reduction sleeve, so that the channel formed in the reduction sleeve is substantially aligned with the rod-receiving channel formed in the bone fixation element so that the spinal rod can pass through the channel and the rod-receiving channel when the bone fixation element is inserted into the reduction sleeve.

19. The reduction sleeve of claim 17, wherein the distance A is at least 20 mm.

20. The reduction sleeve of claim 17, wherein the reduction sleeve includes a pair of break-off points or regions formed in the lower end of the reduction sleeve beneath the channel formed in the sleeve.

21. The reduction sleeve of claim 17, wherein the pair of spaced apart arms formed in the sleeve are joined by a bridge member, the break-off point or region being formed in the bridge member.

22. The reduction sleeve of claim 17, wherein the break-off point or region is formed beneath the channel and extends vertically from the channel to the lower end of the reduction sleeve.

23. The reduction sleeve of claim 17, wherein the reduction sleeve further comprises a plurality of threads for engaging a reduction instrument.

24. The reduction sleeve of claim 23, wherein the plurality of threads are formed on the outer surface of the reduction sleeve.

25. The reduction sleeve of claim 17, wherein the lower end of the reduction sleeve includes a tapered surface sized and configured to receive a correspondingly tapered surface formed on the bone fixation element.

26. The reduction sleeve of claim 17, wherein, once inserted, the bone anchor extends through the lower end of the reduction sleeve such that the bone anchor may be moveable with respect to the bone fixation element and with respect to the reduction sleeve.

27. The reduction sleeve of claim 17, wherein the reduction sleeve includes an alignment mechanism so that the bone fixation element can only be inserted into the reduction sleeve when the rod-receiving channel formed in the bone fixation element is aligned with the channel formed in the reduction sleeve.

28. The reduction sleeve of claim 27, wherein the alignment mechanism is an alignment flat formed in the lower end of the reduction sleeve, the alignment flat being sized and configured to contact a corresponding flat formed on the bone fixation element.

29. The reduction sleeve of claim 17, wherein the reduction sleeve further comprises a protrusion formed on the inner surface of the reduction sleeve, the protrusion projecting inward from the inner surface so that, once inserted, the projection contacts the top surface formed on the bone fixation element.

30. The reduction sleeve of claim 29, wherein the bone fixation element is secured within the reduction sleeve in-between the lower end of the reduction sleeve and the protrusion.

31. A reduction sleeve for facilitating insertion of a longitudinal spinal rod into a bone fixation element, the bone fixation element including a bone anchor and a head portion having a rod-receiving channel formed therein for receiving the spinal rod, the rod-receiving channel defining a pair of spaced apart arms having a top surface, the reduction sleeve comprising:

a longitudinal axis;

an upper end;

a lower end having a tapered surface sized and configured to contact a correspondingly tapered surface formed on the bone fixation element when the bone fixation element is inserted into the reduction sleeve;

an outer surface having a plurality of threads formed thereon for engaging a reduction instrument;

a through-bore extending from the upper end to the lower end, the through-bore defining an inner surface, the inner surface having an inwardly projecting protrusion formed thereon; and

a channel;

wherein the through-bore is substantially perpendicular to the longitudinal axis and the through-bore is sized and configured to receive the bone fixation element; and

wherein the channel is substantially transverse to the longitudinal axis and the channel defines a pair of spaced apart arms having a top surface; and

wherein the reduction sleeve further comprises at least one break-off point or region for facilitating breaking the reduction sleeve into multiple pieces; and

wherein the inwardly projecting protrusion formed on the inner surface of the reduction sleeve is sized and configured to contact the top surface of the bone fixation element, once the bone fixation element has been inserted into the reduction sleeve, so that the bone fixation element can be secured within the reduction sleeve in-between the tapered surface formed in the lower end of the reduction sleeve and the inwardly projecting protrusion.

32. The reduction sleeve of claim 31, wherein the spaced apart arms formed in the reduction sleeve being sized and configured to substantially align with the pair of spaced apart arms formed in the bone fixation element, when the bone fixation element is inserted into the reduction sleeve, so that the channel formed in the reduction sleeve is substantially aligned with the rod-receiving channel formed in the bone fixation element so that the spinal rod can pass through the channel and the rod-receiving channel when the bone fixation element is inserted into the reduction sleeve.

33. The reduction sleeve of claim 31, wherein the reduction sleeve includes a pair of break off points or regions formed in the lower end of the reduction sleeve beneath the channel formed in the sleeve.

34. The reduction sleeve of claim 31, wherein the pair of spaced apart arms formed in the sleeve are joined by a bridge member, the break-off point or region being formed in the bridge member.

35. The reduction sleeve of claim 31, wherein the break-off point or region is formed beneath the channel and extends vertically from the channel to the lower end of the reduction sleeve.

36. The reduction sleeve of claim 31, wherein the reduction sleeve includes an alignment mechanism so that the bone fixation element can only be inserted into the reduction sleeve when the rod-receiving channel formed in the bone fixation element is aligned with the channel formed in the reduction sleeve.

37. The reduction sleeve of claim 36, wherein the alignment mechanism is an alignment flat formed in the lower end of the reduction sleeve, the alignment flat being sized and configured to contact a corresponding flat formed on the bone fixation element.