Percutaneous compression and distraction system

Patent metadata

Field	Value
Publication number	US-9345463-B2
Application number	US-201414547482-A
Country	US
Kind code	B2
Filing date	Nov 19, 2014
Priority date	Sep 25, 2006
Publication date	May 24, 2016
Grant date	May 24, 2016

Abstract

The present invention provides a compression and distraction shaft assembly used to apply compression and distraction to bones including vertebrae. Shaft A assembly and shaft B assembly are attached together via a polyaxial fulcrum. The polyaxial fulcrum allows all rotational degrees of freedom between shaft A assembly and shaft B assembly. Such fulcrum, during compression and distraction, does not impart ancillary stresses or motion to vertebrae. An hourglass-shaped bore for engaging pliers is formed in approximately middle of both the shaft A assembly and the shaft B assembly. Distraction pliers having cylindrical tips are used to apply distraction to vertebrae. Once handles are pressed to impart an appropriate amount of distraction to the vertebrae, they are locked in this position. Compression pliers having cylindrical tips are used to apply compression to vertebrae. Once handles are pressed to impart an appropriate amount of compression to the vertebrae, they are locked in this position.

First claim

The invention claimed is:

1. A system for displacing vertebral bodies, comprising:
a displacement device having a first member and a second member, the first and second members being movable relative to one another;
a first shaft having a distal end and a proximal end, the distal end of the first shaft being removably connectable to a first pedicle screw mountable to a first vertebra of a spine, the first shaft having a first connector at a central portion of the first shaft intermediate the proximal and distal ends of the first shaft; and
a second shaft having a distal end and a proximal end, the distal end of the second shaft being removably connectable to a second pedicle screw mountable to a second vertebra of the spine, the second shaft having a second connector at a central portion of the second shaft intermediate the proximal and distal ends of the second shaft;
wherein the first connector of the first shaft is configured to removably engage the first member of the displacement device and the second connector of the second shaft is configured to removably engage the second member of the displacement device, such that actuation of the displacement device to move the first and second members of the displacement device relative to one another imparts forces on the first and second shafts to displace the first and second vertebrae with respect to one another.

2. The system of claim 1 , wherein the displacement device is configured such that actuation of the displacement device causes the first and second members to move towards one another to compress together the first and second vertebrae.

3. The system of claim 2 , wherein the displacement device includes a first handle and a second handle, and wherein the displacement device is actuated by moving the first and second handles towards one another, which causes the first and second members to move towards one another.

4. The system of claim 1 , wherein the displacement device is configured such that actuation of the displacement device causes the first and second members to move away from one another to distract apart the first and second vertebrae.

5. The system of claim 4 , wherein the displacement device includes a first handle and a second handle, and wherein the displacement device is actuated by moving the first and second handles towards one another, which causes the first and second members to move away from one another.

6. The system of claim 1 , wherein the first connector of the first shaft includes a first opening configured to receive a portion of the first member of the displacement device therein, and wherein the second connector of the second shaft includes a second opening configured to receive a portion of the second member of the displacement device therein.

7. The system of claim 6 , wherein the first and second openings each define an hourglass shape.

8. The system of claim 1 , further comprising a second displacement device having a third member and a fourth member, the third and fourth members being movable relative to one another upon actuation of the second displacement device.

9. The system of claim 8 , wherein the displacement device is configured such that actuation of the displacement device causes the first and second members to move towards one another to compress together the first and second vertebrae, and wherein the second displacement device is configured such that actuation of the second displacement device causes the third and fourth members to move away from one another to distract apart the first and second vertebrae.

10. The system of claim 1 , wherein the proximal ends of the first and second shafts are structured to mate with one another.

11. The system of claim 10 , wherein the proximal ends of the first and second shafts are structured to mate with one another to form a fulcrum about which the first and second shafts are pivotable with respect to one another.

12. The system of claim 11 , wherein the fulcrum is a polyaxial fulcrum.

13. The system of claim 12 , wherein the proximal end of the second shaft includes a spherical ball, and wherein the proximal end of the first shaft includes a bracket configured to receive the spherical ball therein to form the polyaxial fulcrum.

14. The system of claim 13 , wherein the bracket is attached to the proximal end of the first shaft by a pin.

15. The system of claim 1 , wherein the first member of the displacement device includes an end of a first arm, and wherein the second member of the displacement device comprises an end of the second arm, the first and second arms being pivotably coupled together at a pivot point.

16. The system of claim 1 , wherein the first and second connectors are configured to removably engage the respective first and second members of the displacement device in an orientation such that the displacement device extends laterally from the first and second shafts.

17. The system of claim 1 , wherein the displacement device is lockable such that the displacement device maintains the position of the first and second members with respect to one another when the displacement device is locked.

18. The system of claim 17 , wherein the displacement device includes a ratchet mechanism for automatically locking the displacement device after the first and second members have been moved relative to one another.

19. The system of claim 1 , wherein the first connector of the first shaft is configured to removably engage the first member of the displacement device so as to form a first polyaxial pivot between the first shaft and the first member, and wherein the second connector of the second shaft is configured to removably engage the second member of the displacement device so as to form a second polyaxial pivot between the second shaft and the second member.

20. The system of claim 1 , further comprising a rod engageable with the first and second pedicle screws.

21. The system of claim 20 , wherein the distal ends of the first and second shafts each have an arcuate shape configured to receive the rod.

Assignees

• Stryker Europe Holdings I Llc

Inventors

• Butters Joshua A
• Arnett Jeffery

Classifications

• A61B17/7079

  Tools requiring anchors to be already mounted on an implanted longitudinal or transverse element, e.g. where said element guides the anchor motion · CPC title

• A61B17/7001

  Screws or hooks combined with longitudinal elements which do not contact vertebrae (A61B17/7058 takes precedence) · CPC title

• A61B2017/0256

  for the spine · CPC title

• A61B17/025 Primary

  Joint distractors · CPC title

• A61B17/7077

  for moving bone anchors attached to vertebrae, thereby displacing the vertebrae · CPC title