Spinal fusion implant

1. An implant, comprising:

a housing;

a blade having a retracted position in the housing and an extended position where the blade extends outwardly from the housing;

a blade actuating component, the blade actuating component comprising a driven shaft portion;

wherein the blade actuating component is configured to move the blade between the retracted position and the extended position;

the housing including a chamber portion receiving a portion of the driven shaft portion of the blade actuating component;

the driven shaft portion including an opening and a blocking pin disposed within the opening;

wherein, in a first position of the blocking pin within the opening, the blocking pin limits insertion of the blade actuating component;

wherein, in a second position of the blocking pin within the opening, the blade actuating component is unrestricted by the blocking pin; and

wherein the blocking pin is slidable within the opening from the first position to the second position.

2. The implant according to claim 1 , wherein the blade actuating component is configured to be moved in a first direction to move the blade from the retracted position to the extended position; and

wherein the blocking pin is oriented at a non-zero angle that is less than 90 degrees with respect to a direction in which the blade actuating component is driven.

3. The implant according to claim 1 , wherein the blade actuating component includes a tapered portion having a tapered sidewall; and

wherein the blocking pin extends in a direction that is substantially perpendicular to the tapered sidewall.

4. The implant according to claim 1 , wherein the housing of the implant includes a shoulder configured to engage a first end of the blocking pin.

5. The implant according to claim 1 , further including a locking screw configured to prevent the blade actuating component from backing out of the implant once the blade actuating component has been inserted into the implant.

6. The implant according to claim 5 , wherein the locking screw is disposed adjacent to the blade actuating component and includes a flanged head with a rounded segment and a flat segment; and

wherein the locking screw is configured such that, with the blade actuating component inserted into the implant, the locking screw can be turned a predetermined amount to dispose the rounded segment of the flanged head in a position that blocks egress of the blade actuating component from the implant.

7. The implant according to claim 1 , wherein the blocking pin is disposed within the opening with a friction fit.

8. The implant according to claim 7 , wherein, in the first position, the blocking pin extends from a sidewall of the driven shaft portion thereby limiting insertion of the blade actuating component.

9. The implant according to claim 8 , wherein, the opening and the blocking pin are configured such that the friction fit between the blocking pin and the blade actuating component can be overcome by driving the blade actuating component with a deployment force greater than a predetermined threshold force in order to move the blocking pin into the opening to the second position in which insertion of the driven shaft portion of the blade actuating component is unrestricted by the blocking pin.

10. The implant according to claim 9 , wherein the chamber portion has a first width and the driven shaft portion of the blade actuating component has a second width;

wherein the first width of the chamber portion is configured to receive the second width of the driven shaft portion of the blade actuating component;

wherein, in the first position of the blocking pin, the combined effective width of the driven shaft portion and the blocking pin extending from the sidewall of the driven shaft portion is larger than the first width of the chamber portion, thereby limiting insertion of the blade actuating component.

11. An implant, comprising:

a housing;

a blade having a retracted position in the housing and an extended position where the blade extends outwardly from the housing; and

a blade actuating component, the blade actuating component comprising a driven shaft portion;

wherein the blade actuating component is configured to move the blade between the retracted position and the extended position;

the housing including a chamber portion receiving a portion of the driven shaft portion of the blade actuating component; and

the implant further including a blocking element configured to restrict insertion of the blade actuating component by permitting insertion of the blade actuating component when the blade actuating component is subjected to an insertion force exceeding a predetermined threshold force; and

wherein the blocking element includes a blocking pin disposed within an opening in the driven shaft portion of the blade actuating component.

12. The implant of claim 11 , wherein, in a first position, the blocking pin extends from a sidewall of the driven shaft portion thereby limiting insertion of the blade actuating component.

13. The implant of claim 12 ,

wherein, in a second position of the blocking pin, the blade actuating component is unrestricted by the blocking pin.

14. The implant according to claim 11 , wherein the blade actuating component is configured to be moved in a first direction to move the blade from the retracted position to the extended position; and

wherein the blocking pin is oriented at a non-zero angle that is less than 90 degrees with respect to the sidewall of the driven shaft portion.

15. The implant according to claim 11 , wherein the blade actuating component includes a tapered portion having a tapered sidewall; and

wherein the blocking pin extends in a direction that is substantially perpendicular to the tapered sidewall.

16. An implant, comprising:

a housing;

a blade having a retracted position in the housing and an extended position where the blade extends outwardly from the housing;

a blade actuating component, the blade actuating component comprising a driven shaft portion;

wherein the blade actuating component is configured to move the blade between the retracted position and the extended position upon moving the blade actuating component in a first direction;

the housing including a chamber portion receiving a portion of the driven shaft portion of the blade actuating component;

the driven shaft portion including an opening and a blocking pin disposed within the opening;

wherein, in a first position of the blocking pin within the opening, the blocking pin limits insertion of the blade actuating component;

wherein, in a second position of the blocking pin within the opening, the blade actuating component is unrestricted by the blocking pin;

wherein the motion of the blade actuating component can be reversed to retract the blade; and

wherein the blocking pin is slidable within the opening from the first position to the second position.

17. The implant according to claim 16 , wherein the blade actuating component is configured to be moved in the first direction to move the blade from the retracted position to the extended position; and

wherein the blocking pin is oriented at a non-zero angle that is less than 90 degrees with respect to a sidewall of the driven shaft portion.

18. The implant according to claim 16 , wherein the blade actuating component includes a tapered portion having a tapered sidewall; and

wherein the blocking pin extends in a direction that is substantially perpendicular to the tapered sidewall.

19. The implant according to claim 16 , wherein the housing of the implant includes a shoulder configured to engage a first end of the blocking pin.

20. The implant according to claim 16 , wherein the blocking pin is disposed within the opening with a friction fit.