Mating insertion instruments for spinal implants and methods of use

• US 20040162617A1
• Filed: 02/02/2004
• Published: 08/19/2004
• Est. Priority Date: 10/20/1998
• Status: Active Grant

• Current Assignee: Kyphon SARL (Medtronic Plc)
• Original Assignee: St. Francis Medical Technologies, Inc. (Medtronic Plc)
• Inventors: Zucherman, James F., Winslow, Charles J., Hsu, Ken Y., Flynn, John
• Granted Patent: US 7,473,268 B2
• Time in Patent Office: Days
• US Class Current: 623/17.11
• CPC Class Codes: A61B 17/66 Alignment, compression or distraction mechanisms
• CPC Class Codes: A61B 17/7068 Devices comprising separate rigid parts, assembled in situ, to bear on each side of spinous processes; Tools therefor
• CPC Class Codes: A61B 17/7071 Implants for expanding or repairing the vertebral arch or wedged between laminae or pedicles; Tools therefor
• CPC Class Codes: A61B 2017/0256 for the spine
• CPC Class Codes: A61K 31/37 Coumarins, e.g. psoralen

Abstract

Insertion instruments and a main body assembly and a universal wing to be inserted are provided, along with methods of using these instruments for the insertion of the spinal implants in patients to relieve the symptoms of, for example, spinal stenosis, injuries, and degenerative diseases of the spine. The instruments are simply designed and can be disassembled, making cleaning and sterilization easy and convenient. The instruments are designed to engage with and disengage from spinal implants easily, and use of the instrument in spinal implant surgery can be carried out with minimal surgical intervention and does not require general anesthesia. The main body assembly and the universal wing are designed to conveniently be secured to the insertion instruments. In an alternative embodiment the instrument can be nested and at least one instrument can include a handle provided at an angle.

Claims

1. A method for inserting a main body assembly into a spine of a patient, the method comprising the steps of:

a. selecting a main body assembly insertion device, including;

i. an elongated body;

ii. a proximal end having a handle; and

iii. a distal end including an engaging element adapted to engage for implantation the main body assembly, the engaging element comprising at least one alignment pin and an engaging device;

b. selecting the main body assembly for insertion into the spine, the main body assembly comprising;

i. a body portion having a first end, a second end, and a first wing at said first end, said first wing including at least one alignment hole;

ii. a spacer adjacent to the first wing, rotatable about a longitudinal axis; and

iii. a tissue expander at the second end of the main body assembly;

c. operably engaging the main body assembly insertion device with the main body assembly to create an operably engaged assembly by;

i. inserting said at least one alignment pin of said engaging element through said at least one alignment hole of the first wing;

ii. inserting the engaging device into an engaging hole of the main body assembly;

d. using the operably engaged assembly to urge the tissue expander between adjacent spinous processes and to position the spacer between the spinous processes and the first wing adjacent to the spinous processes; and

e. disengaging said main body assembly insertion device from said main body assembly.

2. The method of claim 1 wherein said operably engaging step includes moving the engaging device across an axis of the alignment pin.

3. The method of claim 1 wherein the step of inserting said engaging device into said engaging hole further comprises moving the the engaging device from a first disengaging position to a second engaging position, wherein an axis of the engaging device crosses an axis of the at least one alignment pin.

4. The method of claim 1 wherein the step of inserting said engaging device into said engaging hole further comprises moving the engaging device from a first disengaging position to a second engaging position inside the engaging hole on the spacer.

5. The method of claim 3 wherein the step of moving the engaging device from the first disengaging position to a second engaging position comprises using a spring-loaded mechanism.

6. The method of claim 4 wherein the step of moving the engaging device from the first disengaging position to a second engaging position comprises using a spring-loaded mechanism.

7. The method of claim 1 wherein the selecting step includes selecting a main body assembly insertion device including an engaging element further comprising a device locking pin adapted to connect with a locking pin hole of the first wing wherein an axis of said device locking pin crosses an axis of the at least one alignment pin.

8. The method of claim 1 wherein the operably engaging step further comprises inserting a device locking pin of the engaging element of the main body assembly insertion device into a locking pin hole of the first wing, wherein an axis of said device locking pin crosses an axis of the at least one alignment pin.

9. The method of claim 8 wherein the inserting step further comprises moving the device locking pin from a first disengaging position to a second engaging position, wherein the axis of said device locking pin crosses the axis of the at least one alignment pin.

10. The method of claim 1 wherein the operably engaging step further comprises moving a device locking pin across an axis of the alignment pin.

11. The method of claim 8 wherein the operably engaging step further comprises moving the device locking pin across an axis of the alignment pin.

18. The method of claim 1 further comprising using at least one trial implant to select an appropriately-sized main body assembly.

19. The method of claim 1 including the steps of:

selecting a second wing insertion device including at least one alignment pin;

selecting a second wing comprising least one alignment pin hole, adapted to receive the at least one alignment pin of the second wing insertion device, and a second wing locking mechanism that can secure the second wing to the main body assembly;

engaging said second wing with said second wing insertion device by inserting the at least one alignment pin into the at least one alignment pin hole; and

using the second wing insertion device and the main body assembly insertion device to connect the second wing with the main body assembly in the patient after first using the main body assembly insertion device to urge the main body assembly between adjacent spinous processes.

24. The method of claim 9 further including the step of determining the size of an appropriate implant to place in the patient by sizing with the plurality of test spacer implants.

12. A method for inserting a second wing on a main body assembly implanted between adjacent spinous processes of a spine of a patient, the method comprising:

a. positioning a main body assembly comprising a spacer located between a first wing and a tissue expander between adjacent spinous processes, the first wing adjacent to one side of the spinous processes, and the tissue expander protruding on the opposite side of the spinous processes;

b. selecting a second wing insertion device adapted to removably engage the second wing, the second wing insertion device comprising;

i. at least one alignment pin; and

ii. a rotatable driver;

c. selecting the second wing, the second wing comprising;

i. at least one alignment pin hole adapted to receive the at least one alignment pin of the second wing insertion device; and

ii. a second wing locking mechanism;

d. engaging the second wing with the second wing insertion device by engaging the driver with the second wing; and

mating the at least one alignment pin with the at least one alignment pin hole;

e. using the second wing insertion device to urge said engaged second wing into engagement with the main body assembly;

f. securing the second wing to the main body assembly by rotating the driver; and

g. disengaging the second wing insertion device.

13. The method of claim 12 wherein said using step includes moving said second wing along a posterior-to-anterior line.

14. The method of claim 12 wherein the selecting step of the second wing further comprises selecting a second wing further comprising a mounting ring with a bore, said bore adapted to receive a bolt, wherein said bolt is adapted rotably and disengageably to connect at a first end with the driver of the second wing insertion device and to engage at a second end with a compatible bore in the tissue expander.

15. The method of claim 14 wherein the engaging step further comprises engaging the driver with the first end of the bolt.

16. The method of claim 15 wherein the using step further comprises inserting the bolt into the compatible bore in the tissue expander.

17. The method of claim 16 wherein the rotating the driver step drives the bolt into the compatible bore in the tissue expander.

20. The method of claim 12 including the steps of:

selecting a main body assembly insertion device;

selecting said main body assembly;

engaging said main body assembly with the main body assembly insertion device; and

using the main body insertion device to secure the main body assembly with the second wing.

21. The method of claim 20 wherein the engaging step further comprises inserting at least one alignment pin of the main body assembly insertion device into at least one alignment hole on the main body assembly.

22. The method of claim 21 wherein the inserting step further comprises aligning the at least one alignment pin with the at least one alignment hole wherein the at least one alignment hole is on a first wing of the main body assembly.

23. A method for inserting an implant between adjacent spinous processes of a spine of a patient, the method comprising the steps of:

selecting a plurality of test spacer implants of varying sizes;

inserting a first test spacer implant to distract apart at least one of bone and tissue;

using a subsequent test spacer implant of a larger size than the first test spacer implant in order to further distract apart at least one of tissue and bone; and

implanting the implant in the location created by the distraction through the inserting and using steps.

25. A method of using a plurality of tools to insert a distraction implant laterally between adjacent spinous processes, the method comprising the steps of:

engaging a first tool with a main body assembly of a distraction implant;

using the engaged first tool to insert the main body assembly between adjacent spinous processes;

mounting a wing on a second tool;

aligning the first and second tools to align the wing with the main body assembly;

securing the wing to the main body assembly;

disengaging the first tool and the second tool.

26. The method in claim 25 further comprising the initial step of using successively larger trial implants mounted on a series of third tools to provide distraction to increase distraction between adjacent spinous processes.

27. The method of claim 25 comprising the further step of inserting a bolt through a bore defined by a mounting ring of the wing before the mounting step.

28. The method of claim 27 wherein the securing step further comprises using the bolt to secure the wing to the main body assembly.

29. The method of claim 25 wherein an insertion tip of the first tool engages the main body assembly by additional steps comprising:

retracting a spring loaded insertion rod that extends to form both a locking pin and an engagement pin protruding at the insertion tip;

engaging at least one alignment pin of the insertion tip with an alignment hole in a first wing at a first end of the main body assembly; and

allowing the spring-loaded locking pin to spring forward into a locking pin hole in the first wing, and the engagement pin to spring forward into an engagement hole on a spacer of the main body assembly located adjacent to the first wing.

30. The method of claim 25 wherein the mounting step involving the second tool and the wing comprises the additional steps of:

retracting a spring-loaded insertion rod of the second tool, the insertion rod comprising a driver wherein the insertion rod is rotatable about a longitudinal axis of the insertion rod;

aligning at least one alignment pin on the insertion tip of the second tool with at least one alignment hole on the universal wing; and

allowing the insertion rod of the second tool to spring forward and to bring the driver operably into contact with the wing.

31. The method of claim 30 wherein the securing step further comprises rotating the insertion rod of the second tool about its longitudinal axis to drive a bolt of the wing into a threaded hole on the main body assembly.

32. The method of claim 31 wherein the rotating step comprises turning a knob at the proximal end of the second tool to rotate the insertion rod.

33. The method of claim 25 wherein the aligning step comprises mating a member on an elongated body of one of the first tool and the second tool, with a recess on an elongated body of the other of the first tool and the second tool.

34. An improved method for implanting an implant to distract adjacent spinous processes, the improvement comprising nesting tools to align and position the implant in a patient.