SPINAL FUSION IMPLANT FOR OBLIQUE INSERTION

• US 20160310294A1
• Filed: 04/25/2016
• Published: 10/27/2016
• Est. Priority Date: 04/23/2015
• Status: Active Grant

• Current Assignee: Camber Spine Technologies, LLC
• Original Assignee: Camber Spine Technologies, LLC
• Inventors: McConnell, Jeffrey R., Duffield, William
• Granted Patent: US 10,555,818 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61F 2/4455 for the fusion of spinal bodies, e.g. intervertebral fusion of adjacent spinal bodies, e.g. fusion cages intervertebral discs A61F2/442
• CPC Class Codes: A61F 2/447 substantially parallelepipedal, e.g. having a rectangular or trapezoidal cross-section
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2/4684 Trial or dummy prostheses
• CPC Class Codes: A61F 2002/3008 radio-opaque, e.g. radio-opaque markers
• CPC Class Codes: A61F 2002/30151 rhomboidal or parallelogram-shaped
• CPC Class Codes: A61F 2002/30156 triangular
• CPC Class Codes: A61F 2002/30593 hollow
• CPC Class Codes: A61F 2002/30616 Sets comprising a plurality of prosthetic parts of different sizes or orientations
• CPC Class Codes: A61F 2002/30797 internally-threaded
• CPC Class Codes: A61F 2002/30828 parallel
• CPC Class Codes: A61F 2002/30904 serrated profile, i.e. saw-toothed
• CPC Class Codes: A61F 2002/448 comprising multiple adjacent spinal implants within the same intervertebral space or within the same vertebra, e.g. comprising two adjacent spinal implants
• CPC Class Codes: A61F 2230/0082 parallelepipedal

Abstract

Intervertebral spinal fusion implants for interbody fusion of the anterior column of the spine are described. The implants have a substantially bi-convex or a substantially offset bi-convex shape. The implants are placed through a transforaminal or posterior approach at an oblique insertion angle. The implants have an outermost point on the superior convex surface and an outermost point on the inferior convex surface and four edges of differing heights. The outermost superior and inferior points of the implants are connected with the four edges with convex surfaces of different curvatures. The curvatures of the convex surfaces of the implants are designed to match the curvatures of concave vertebral surfaces when the implants are inserted at an oblique insertion angle.

Claims

1. An intervertebral fusion implant for spinal fusion between two adjacent vertebrae comprising

a superior convex surface,

an inferior convex surface, and

four vertical edges, wherein each edge has a different height than the other edges, wherein each edge comprises a superior end and an inferior end, wherein each superior end terminates at the superior convex surface, and wherein each inferior end terminates at the inferior convex surface,

wherein the superior convex surface comprises a first outermost point serving as an apex, a lower-most lateral point and a lower-most medial point, and

wherein the inferior convex surface comprises a second outermost point, an upper-most lateral point and an upper-most medial point.

2. The intervertebral fusion implant of claim 1, wherein the first outermost point and the second outermost point are positioned about the middle of the implant, and the implant has a bi-convex shape.

3. The intervertebral fusion implant of claim 1, wherein the first outermost point and the second outermost point are positioned anteriorly or posteriorly, and the implant has an offset bi-convex shape.

4. The intervertebral fusion implant of claim 1, wherein the height of an imaginary line connecting the apex and the second outermost point is the apex height, and wherein the apex height is greater than each of the heights of the four vertical edges.

5. The intervertebral fusion implant of claim 1, wherein the implant further comprises an opening for receiving a bone graft material.

6. The intervertebral fusion implant of claim 1, wherein the superior convex surface and inferior convex surface further comprise one or more bone engagement members.

7. The intervertebral fusion implant of claim 1, wherein curvatures of the inferior and superior convex surfaces match the concavities of the two adjacent vertebrae at an insertion angle when the insertion angle is an oblique angle relative to the median plane of the spine.

8. The intervertebral fusion implant of claim 1, wherein a curvature of the superior convex surface is defined by connecting the first outermost point to each of the superior ends of each of the four vertical edges to form four superior curved lines of different curvatures, and

wherein a curvature of the inferior convex surface is defined by connecting the second outermost point to each of the inferior ends of each of the four edges to form four inferior curved lines of different curvatures.

9. The intervertebral fusion implant of claim 8,

wherein the curvature of each of the superior curved lines or the inferior curved lines is calculated using Equation 1:

10. The intervertebral fusion implant of claim 9, wherein a ranges from 0.03 mm to 0.88 mm and b ranges from 5 mm to 21 mm, and wherein the implant has a bi-convex shape.

11. The intervertebral fusion implant of claim 9, wherein a ranges from 0.5 mm to 4.2 mm and b ranges from 5 mm to 28.3 mm, and wherein the implant has an offset bi-convex shape.

12. The intervertebral fusion implant of claim 2, further comprising a central opening and an oblique divider, and wherein the apex is located on the oblique divider.

13. The intervertebral fusion implant of claim 1, wherein

(a) the first outermost point of the superior convex surface is positioned about the middle of the superior convex surface,

(b) the second outermost point of the inferior convex surface is positioned about the middle of the inferior convex surface,

(c) the four vertical edges are:

a(n) anterior lateral vertical edge, vertical anterior medial edge, posterior medial vertical edge, and posterior lateral vertical edge, and

wherein the implant further comprises;

(d) an anterior vertical surface and a posterior vertical surface,

(e) a lateral longitudinal surface and a medial longitudinal surface,

(f) a central opening, and

(g) an oblique divider dividing the central opening,

wherein the distance between the first outermost point and the second outermost point is the apex height, and

wherein the apex height is greater than each of the heights of the four vertical edges, and

wherein the implant has a bi-convex shape.

14. The intervertebral fusion implant of claim 13, wherein a first curvature of the superior convex surface and a second curvature of the inferior convex surface along a sagittal plane of the implant form a sagittal profile of the implant, and

wherein the first curvature is defined by connecting the first outermost point with each of the superior ends of the four vertical edges to form four superior curved lines, and wherein the second curvature is defined by connecting the second outermost point with each of the inferior ends of the four vertical edges to form four inferior curved lines,

wherein the curvature of each of the superior curved lines or the inferior curved lines is calculated from Equation 1:

15. The intervertebral fusion implant of claim 13, wherein a first curvature of the superior convex surface and a second curvature of the inferior convex surface along a coronal plane of the implant form a coronal profile of the implant, and

wherein the first curvature is defined by connecting the first outermost point with the lower-most lateral point and the lower-most medial point to form two superior curved lines, and wherein the second curvature is defined by connecting the second outermost point with the upper-most lateral point and the upper-most medial point to form two inferior curved lines,

wherein the curvature of each of the superior curved lines or the inferior curved lines is calculated from Equation 1:

16. The intervertebral fusion implant of claim 14, wherein a ranges from 0.03 mm to 0.15 mm and b ranges from 11.5 mm to 21 mm.

17. The intervertebral fusion implant of claim 15, wherein a ranges from 0.5 mm to 0.88 mm and b ranges from 5 mm to 6 mm.

18. The intervertebral fusion implant of claim 1, wherein

(a) the first outermost point of the superior convex surface is positioned anteriorly or posteriorly on the superior convex surface,

(b) the second outermost point of the inferior convex surface is positioned anteriorly or posteriorly on the inferior convex surface, (c) the four vertical edges are:

a(n) anterior lateral vertical edge, anterior medial vertical edge, posterior medial vertical edge, and posterior lateral vertical edge, and

wherein the implant further comprises;

(d) an anterior vertical surface and a posterior vertical surface,

(e) a lateral longitudinal surface and a medial longitudinal surface, and

(f) a central opening,

wherein the distance between the first outermost point and the second outermost point is the apex height, and

wherein the apex height is greater than each of the heights of the four vertical edges, and

wherein the implant has an offset bi-convex shape.

19. The intervertebral fusion implant of claim 18, wherein a first curvature of the superior convex surface and a second curvature of the inferior convex surface along a sagittal plane of the implant form a sagittal profile of the implant, and

wherein the first curvature is defined by connecting the first outermost point with each of the superior ends of the four vertical edges to form four superior curved lines, and wherein the second curvature is defined by connecting the second outermost point with each of the inferior ends of the four vertical edges to form four inferior curved lines,

wherein the curvature of each of the superior curved lines or the inferior curved lines is calculated from Equation 1:

20. The intervertebral fusion implant of claim 18, wherein a first curvature of the superior convex surface and a second curvature of the inferior convex surface along a coronal plane of the implant form a coronal profile of the implant, and

wherein the first curvature is defined by connecting the first outermost point with the lower-most lateral point and the lower-most medial point to form two superior curved lines, and wherein the second curvature is defined by connecting the second outermost point with the upper-most lateral point and the upper-most medial point to form two inferior curved lines,

wherein the curvature of each of the superior curved lines or the inferior curved lines is calculated from Equation 1:

21. The intervertebral fusion implant of claim 19, wherein a ranges from 1.6 mm to 4.2 mm and b ranges from 7.2 mm to 28.3 mm.

22. The intervertebral fusion implant of claim 20, wherein a ranges from 0.5 mm to 1.1 mm and b ranges from 5 mm to 6 mm.

23. A spinal fusion method for increasing or decreasing a lordotic angle comprising inserting the intervertebral fusion implant of claim 1 between two adjacent vertebrae in a patient in need of a spinal fusion via a transforaminal or posterior approach at an oblique insertion angle.

24. The method of claim 23, wherein the oblique insertion angle ranges from 30°

to 40°

relative to a medial axis of a spine.

25. The method of claim 23, further comprising

attaching to one or more of the vertebrae one or more supplemental fixation systems, and

adjusting the supplemental fixation system to increase or decrease the lordotic angle.