Spinal stabilization method

• US 5,015,255 A
• Filed: 05/10/1989
• Issued: 05/14/1991
• Est. Priority Date: 05/10/1989
• Status: Expired due to Term

• Current Assignee: Zimmer Spine, Inc. (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Spine-Tech, Inc. (Sulzer Medica)
• Inventors: Kuslich, Stephen D.
• Primary Examiner(s): Isabella, David J.
• Application Number:
  US07/350,126
• Time in Patent Office: 734 Days
• Field of Search: 606/59, 606/60, 606/76, 606/79-86, 606/90
• US Class Current: 128/898
• CPC Class Codes: A61B 17/1671 for the spine
• CPC Class Codes: A61B 17/1757 for the spine
• CPC Class Codes: A61B 17/32002 with continuously rotating, oscillating or reciprocating cutting instruments
• CPC Class Codes: A61B 2017/00261 Discectomy
• CPC Class Codes: A61F 2/442 Intervertebral or spinal discs, e.g. resilient non-disc-shaped intervertebral inflatable pockets A61F2/441; non-disc-shaped intervertebral fusion implants A61F2/4455
• CPC Class Codes: A61F 2/446 having a circular or elliptical cross-section substantially parallel to the axis of the spine, e.g. cylinders or frustocones
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2002/2835 Bone graft implants for filling a bony defect or an endoprosthesis cavity, e.g. by synthetic material or biological material
• CPC Class Codes: A61F 2002/2839 Bone plugs or bone graft dowels
• CPC Class Codes: A61F 2002/4649 Bone graft or bone dowel harvest sites
• CPC Class Codes: Y10T 408/8592 Coaxial with tool-axis

Abstract

A spinal stabilization method is disclosed for fusing contiguous vertebra in an animal spine. The method includes the steps of forming an access opening into at least a layer of tissue disposed between contiguous vertebra to be fused. Additional portions of the tissue layer as well as material of the vertebra body portions are removed to form an enlarged chamber disposed between the contiguous vertebra. The chamber is at least partially filled with a graft medium.

Claims

1. A spinal stabilization method for a spine having contiguous vertebra with each of such vertebra including a body portion and with said body portions spaced apart by a layer of tissue, said method comprising the steps of:

forming an access opening into at least said layer of tissue with said access opening extending at least partially between said contiguous vertebra;

inserting an expandable cutting tool into said access opening with said cutting tool having a retracted size selected for said tool to pass into said opening, said cutting tool further having an expanded size selected for said tool to cut into an area greater than an area of said access opening;

removing at least a portion of said layer of tissue and said body portions with said expandable cutting tool to form an enlarged chamber disposed between said contiguous vertebra with said enlarge chamber having a cross-sectional area greater than a cross-sectional area of said access opening; and

at least partially filling said enlarged chamber with a graft medium.

2. A method according to claim 1 wherein said access opening is formed into said layer generally radially to an axis of said contiguous vertebra.

3. A spinal stabilization method for a spine having contiguous vertebra with each of such vertebra including a body portion with said body portion spaced apart by a layer of tissue, said method including a use of a surgical tool having a distal end of predetermined exterior dimensions and with said distal end including cutting means for cutting said vertebra body portions to form a chamber sized greater than said external dimensions, said method including the steps of:

locating said layer of tissue;

forming an access opening into at least said layer with said access opening extending at least partially between said contiguous vertebra;

inserting said distal end into said access opening with said exterior dimensions sized for said distal end to pass into said access opening said cutting means expandable to a size greater than said exterior dimension;

operating said tool to expand said cutting means to cut at least a portion of said layer and said body portion of said contiguous vertebra to form a chamber disposed between said contiguous vertebra with said chamber sized greater than said access opening; and

removing said distal end.

4. A method according to claim 3 wherein said access opening is formed into said layer generally radially to an access of said contiguous vertebra.

5. A method according to claim 3 wherein said cutting means includes control means for varying a size of a chamber formed by operating said tool, said method including the steps of operating said control means to sequentially increase the size of said chamber from a size approximate a size of said access opening to a desired final size.

6. A method according to claim 5 further including the steps of periodically cleansing debris material during operation of said tool.

7. A method according to claim 3 comprising filling said enlarged chamber with graft medium.

8. A spinal stabilization method for a human spine having contiguous vertebra with each of such vertebra including a body portion of generally known dimension and with contiguous body portions spaced apart by a layer of tissue generally predetermined dimension, said method including the use of a surgical tool having a distal end of predetermined exterior dimension sized for the distal end of predetermined exterior dimension sized for the distal end to be inserted within the patient'"'"'s body and located against said layer without the distal end interfering with predetermined anatomical parts upon location against said layer, said distal end including cutting means for cutting vertebra body material to form a chamber sized greater than said external dimensions, said method including the steps of:

locating said layer of tissue;

forming an access opening into at least said layer with said access opening extending at least partially between said contiguous vertebra;

inserting said distal end into said opening with said exterior dimensions sized for said distal end to pass into said access opening said cutting means expandable to a size greater than said exterior dimension;

operating said tool to expand said cutting means to cut at least a portion of said layer and said contiguous body portions to form a chamber disposed between said contiguous vertebra with said chamber sized greater than said distal end; and

removing said distal end.

9. A method according to claim 8 wherein said access opening is formed into said layer generally radially to an axis of said contiguous vertebra.

10. A method according to claim 8 wherein said cutting means includes control means for varying a size of a chamber formed by operating said tool, said method including the steps of operating said control means to sequentially increase the size of said chamber from a size approximate that of said access opening to a desired final size.

11. A method according to claim 8 comprising at least partially filling said enlarged chamber with a graft medium.

12. A method according to claim 8 wherein said enlarged chamber is formed in direct communication with an exterior of s id spine.

13. A method according to claim 8 wherein said access opening is formed with a depth greater than a length of said cutting means and said chamber is formed completely with said spine and communicating with an exterior of said spine through said access opening.

18. A method according to claim 8 wherein said distal end external dimensions are sized to be received between opposing vertebra through partially removed laminar without destruction of a facet joint.

14. A spinal stabilization method for a human spine having contiguous vertebra with each of said vertebra including a body portion of generally known dimension and with contiguous body portions spaced apart by a layer of tissue of generally predetermined dimension, said method including the use of a surgical tool having a distal end of predetermined exterior dimension sized for the distal end of predetermined exterior dimension sized for the distal end to be inserted within a patient'"'"'s body and located against said layer without the distal end interfering with predetermined anatomical parts upon location against said layer, said distal end including retractable cutting blade disposed for cutting upon rotation of said distal end about a distal end access, a chamber having a diameter greater than said external dimensions, said cutting blade sized to be received between contiguous vertebra with said cutting blade further sized to cut away bone material from opposing vertebra body upon rotation of said distal end, said method including the steps of:

locating said layer of tissue;

forming an access opening into at least said layer with said access opening extending at least partially between said contiguous vertebra;

inserting said distal end into said opening, said exterior dimensions selected for said distal end to pass into said access opening said cutting means expandable to a size greater than said exterior dimension;

operating said tool to change said cutting blade to rotate about said access to cut at least a portion of said layer in said contiguous body portions to form a chamber disposed between said contiguous vertebra with said chamber sized greater than said distal end; and

removing said distal end.

15. A method according to claim 14 comprising filling said enlarged chamber with a graft medium.

16. A method according to claim 14 wherein said access opening is formed into said layer generally radially to an axis of said contiguous vertebra.

17. A method according to claim 14 wherein said cutting means includes control means for varying a size of said chamber formed by operating said tool, said method including the steps of operating said control means to sequentially increase the size of said chamber from a size approximate of said access opening to a desired final size.

19. A method according to claim 14 wherein said distal end external dimensions are sized to be received between opposing vertebra through partially removed laminar without destruction of a facet joint.