Spinous process clamp for spinal fusion and method of operation

• US 6,364,883 B1
• Filed: 02/23/2001
• Issued: 04/02/2002
• Est. Priority Date: 02/23/2001
• Status: Active Grant

• Current Assignee: Albert N. Santilli
• Original Assignee: Albert N. Santilli
• Inventors: Santilli, Albert N.
• Primary Examiner(s): Philogene, Pedro
• Application Number:
  US09/792,696
• Time in Patent Office: 403 Days
• Field of Search: 606/69, 606/70, 606/72, 606/75, 606/64, 606/86, 606/61, 606/104, 606/151, 623/17.11, 623/17.15, 623/16.11
• US Class Current: 606/279
• CPC Class Codes: A61B 17/7055 connected to sacrum, pelvis or skull
• 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: Y10S 606/90 Lumbar stabilizer

Abstract

A spinous process clamp employs a pair of elongate plates that are positioned on either side of the spinous processes of vertebrae that are to be fused. The plates are joined by fasteners, preferably bolts and nuts. When the bolts and nuts are tightened, the spinous processes are clamped between the plates, thereby preventing motion between the clamped vertebral bodies. In an embodiment especially adapted for immobilizing a patient'"'"'s lower lumbar region, the clamp is provided with projections that engage the patient'"'"'s sacrum and brackets that are connected to the sacrum. The invention eliminates the use of pedicle screws, wires, or hooks, thereby greatly simplifying the installation process.

Claims

1. A spinous process clamp for spinal fusion, comprising:

a first plate having an overall length (L) and a width (W), the first plate having a first end and a second end spaced apart the length (L), a posterior edge and an anterior edge spaced apart the width (W), the first plate when viewed from the side being curved about a longitudinal axis that approximately conforms to the radius of curvature of the portion of the patient'"'"'s spine to be immobilized, and a plurality of openings spaced along the longitudinal axis;

a second plate that is substantially identical to the first plate; and

a plurality of fasteners adapted to extend through the openings in the first and second plates, the fasteners being of a length that will permit a patient'"'"'s spinous processes to be clamped between the first and second plates.

2. The clamp of claim 1, wherein the radius of curvature of the longitudinal axis is constant.

3. The clamp of claim 2, wherein the radius of curvature of the longitudinal axis is approximately 12.0 inches.

4. The clamp of claim 1, wherein the length (L) is within the range of approximately 3.125 to 4.75 inches and the width (W) is approximately 0.4375 inch.

5. The clamp of claim 1, wherein the first and second plates are flat, and each has a thickness (T) that is constant along the length of the plate.

6. The clamp of claim 5, wherein the thickness (T) is approximately 0.1875 inch.

7. The clamp of claim 1, further comprising a pair of projections extending from the second end, the projections being of a size and shape to conform to the upper portion of the patient'"'"'s sacrum.

8. The clamp of claim 7, wherein the projections include a rounded end.

9. The clamp of claim 1, further comprising a connection between the plates and the patient'"'"'s sacrum.

10. The clamp of claim 9, wherein the connection between the plates and the patient'"'"'s sacrum includes:

a pair of bone screws;

a bracket for each of the plates, each bracket having first and second legs, the first leg adapted to be connected to the second end of a selected plate and the second leg adapted to be connected to the patient'"'"'s sacrum;

each of the first and second legs having an opening;

the first leg being connected to the second end by a fastener that extends

through the opening in the first leg; and

the second leg being connected to the sacrum by a bone screw that extends through the opening in the second leg.

11. The clamp of claim 1, wherein the fasteners are bolts and nuts.

12. A spinous process clamp for spinal fusion, comprising:

a first, generally flat plate having an overall length (L), a thickness (T), and a width (W), the first plate having a first end and a second end spaced apart the length (L), opposed sides spaced apart a distance equal to the thickness (T), and a posterior edge and an anterior edge spaced apart the width (W), the first plate when viewed from the side being curved, and when viewed from the front being straight, the plate having a curved longitudinal axis that approximately conforms to the radius of curvature of the portion of the patient'"'"'s spine to be immobilized and a plurality of openings spaced along the longitudinal axis;

a second plate that is substantially identical to the first plate;

a plurality of bolts adapted to extend through the openings in the first and second plates, the bolts being of a length that will permit a patient'"'"'s spinous processes to be clamped between the first and second plates; and

a plurality of nuts adapted to be threaded onto the bolts to clamp the plates in place.

13. The clamp of claim 12, wherein the radius of curvature is constant and is approximately 12.0 inches.

14. The clamp of claim 12, wherein the length (L) is within the range of approximately 3.125 to 4.75 inches, the thickness (T) is approximately 0.1875 inch, and the width (W) is approximately 0.4375 inch.

15. The clamp of claim 12, further comprising a pair of projections extending from the second end, the projections being of a size and shape to conform to the upper portion of the patient'"'"'s sacrum, each of the projections including a rounded end.

16. The clamp of claim 12, further comprising a connection between the plates and the patient'"'"'s sacrum that includes:

a pair of bone screws;

a bracket for each of the plates, each bracket having first and second legs, the first leg adapted to be connected to the second end of a selected plate and the second leg adapted to be connected to the patient'"'"'s sacrum;

each of the first and second legs having an opening;

the first leg being connected to the second end by a fastener that extends through the opening in the first leg; and

the second leg being connected to the sacrum by a bone screw that extends through the opening in the second leg.

17. A method of spinal fusion, comprising the steps of:

providing a first plate having an overall length (L) and a width (W), the first plate having a first end and a second end spaced apart the length (L), a posterior edge and an anterior edge spaced apart the width (W), the first plate when viewed from the side being curved, the plate having a curved longitudinal axis and a plurality of openings spaced along the longitudinal axis;

providing a second plate that is substantially identical to the first plate;

providing a plurality of fasteners adapted to extend through the openings in the first and second plates, the fasteners being of a length that will permit a patient'"'"'s spinous processes to be clamped between the first and second plates;

disposing the first and second plates on either side of a patient'"'"'s spinous processes with the openings in the plates in alignment with each other and with spaces between the patient'"'"'s spinous processes;

inserting the fasteners through selected openings in the plates and the spaces between the patient'"'"'s spinous processes; and

tightening the fasteners until the spinous processes disposed between the plates are clamped securely.

18. The method of claim 17, further comprising the steps of:

providing the first and second plates with a pair of projections extending from the second end, the projections being of a size and shape to conform to the upper portion of the patient'"'"'s sacrum; and

placing the projections against the patient'"'"'s sacrum prior to the steps of inserting the fasteners and tightening the fasteners.

19. The method of claim 17, further comprising the steps of:

providing a bracket for each of the plates, each bracket having first and second legs, each of the first and second legs having an opening;

disposing the first leg of each bracket adjacent the second end of a selected plate and the second leg of each bracket adjacent the patient'"'"'s sacrum;

providing a pair of bone screws;

extending a fastener through the opening in the first leg of each bracket and the spaced-apart plates prior to the step of tightening the fasteners;

drilling an opening in the patient'"'"'s sacrum in alignment with the opening in the second leg of each bracket; and

inserting a bone screw through the opening in the second leg of each bracket into the opening in the sacrum, whereby the brackets will be secured to the sacrum.