Intervertebral implant devices

1. A spinal implant, comprising:

a first sidewall;

a second sidewall opposite from the first sidewall;

a first frictional surface configured for engaging a first vertebra;

a second frictional surface configured for engaging a second vertebra adjacent to the first vertebra;

a first end wall joining the first sidewall and the second sidewall at a first end of the spinal implant;

a second end wall joining the first sidewall and the second sidewall at a second end of the spinal implant opposite from the first end; and

a retention structure positioned within the second end wall;

wherein the second end wall comprises a recess formed by a first wall portion and a second wall portion arranged at an angle to one another to form a fish-tailed structure, and wherein the fish-tailed structure defines the recess between the first wall portion and the second wall portion;

wherein the retention structure is positioned within the fish-tailed structure such that the retention structure does not extend beyond the fish-tailed structure; and

wherein the retention structure is configured to engage a surgical implantation device.

2. The spinal implant of claim 1 , wherein the retention structure comprises a hole.

3. The spinal implant of claim 2 , wherein the hole comprises a threaded hole.

4. The spinal implant of claim 2 , wherein the hole is positioned at a location at least substantially equidistant from the first frictional surface and the second frictional surface.

5. The spinal implant of claim 4 , wherein the hole is positioned at a location at least substantially equidistant from the first sidewall and the second sidewall.

6. The spinal implant of claim 1 , wherein the fish-tailed structure is formed so as to extend at least substantially all of the way along at least one dimension of the second end wall.

7. The spinal implant of claim 6 , wherein the fish-tailed structure is formed so as to extend at least substantially all of the way between the first frictional surface and the second frictional surface.

8. The spinal implant of claim 7 , wherein the first wall portion extends from and joins with the first sidewall, and wherein the second wall portion extends from and joins with the second sidewall, so as to form the fish-tailed structure.

9. The spinal implant of claim 1 , wherein the first sidewall and the second sidewall comprise opposed arcuate surfaces.

10. The spinal implant of claim 1 , wherein the first frictional surface comprises a plurality of raised structures, and wherein the second frictional surface comprises a plurality of raised structures.

11. An intervertebral implant device, comprising:

a pair of opposed sidewall surfaces;

a pair of opposed frictional surfaces;

a first end wall joining the pair of opposed sidewall surfaces;

a second end wall recessed at least in part and joining the pair of opposed sidewall surfaces;

a fish-tailed structure positioned within the second end wall when viewed from one of the opposed frictional surfaces, wherein the fish-tailed structure is formed so as to extend between at least one of the opposed sidewall surfaces and the opposed frictional surfaces, and wherein the fish-tailed structure defines a recess within the second end wall; and

a hole positioned within the fish-tailed structure, wherein the hole is configured to engage a surgical implantation device, wherein the hole is positioned so as to avoid extending beyond the fish-tailed structure, and wherein the hole is formed within the fish-tailed structure such that the hole extends in a direction at least substantially between the first end wall and the second end wall.

12. The intervertebral implant device of claim 11 , wherein the fish-tailed structure is formed so as to extend at least substantially uninterrupted between the opposed sidewall surfaces.

13. The intervertebral implant device of claim 11 , wherein the fish-tailed structure is formed so as to extend at least substantially uninterrupted between the opposed frictional surfaces.

14. The intervertebral implant device of claim 11 , wherein the second end wall comprises a first wall portion and a second wall portion arranged at an angle to one another and collectively forming the fish-tailed structure.

15. The intervertebral implant device of claim 14 , wherein the fish-tailed structure is formed such that the first wall portion and the second wall portion extend from one another at an angle greater than ninety degrees.

16. The intervertebral implant device of claim 14 , wherein the fish-tailed structure further comprises a third wall portion joining the first wall portion and the second wall portion.

17. The intervertebral implant device of claim 16 , wherein the third wall portion comprises a flat wall.

18. The intervertebral implant device of claim 11 , wherein the hole is positioned centrally within the second end wall with respect to the fish-tailed structure.

19. The intervertebral implant device of claim 11 , wherein the fish-tailed structure extends between the pair of opposed sidewalls, and wherein the fish-tailed structure extends between the pair of opposed frictional surfaces.

20. The intervertebral implant device of claim 19 , wherein the fish-tailed structure extends at least substantially uninterrupted between the pair of opposed sidewalls, and wherein the fish-tailed structure extends at least substantially uninterrupted between the pair of opposed frictional surfaces.

21. An intervertebral implant device, comprising:

a pair of opposed sidewall surfaces;

a pair of opposed frictional surfaces each comprising a plurality of raised structures;

a first end wall joining the pair of opposed arcuate surfaces;

a second end wall recessed at least in part and joining the pair of opposed arcuate surfaces, the second end wall comprising a first wall portion and a second wall portion arranged at an angle to one another and collectively forming a fish-tailed structure when viewed from one of the opposed frictional surfaces, wherein the fish-tailed structure is formed so as to extend between the opposed frictional surfaces, wherein the fish-tailed structure defines a recess within the second end wall, and wherein the fish-tailed structure is formed so as to extend between the opposed sidewall surfaces; and

a hole positioned within the fish-tailed structure;

wherein the hole is configured to engage a surgical implantation device;

wherein the first wall portion extends between the opposed frictional surfaces from an upper frictional surface to a lower frictional surface; and

wherein the second wall portion extends between the opposed frictional surfaces from the upper frictional surface to the lower frictional surface.

22. The intervertebral implant device of claim 21 , wherein the fish-tailed structure is formed so as to extend at least substantially uninterrupted between the opposed sidewall surfaces.