Spinal cage having deployable member

1. A spinal cage assembly, comprising:

a spinal cage comprising a support structure suitable to maintain two vertebrae separate from each other and having an interior having at least some empty space;

a spin-plate engaged with said spinal cage and rotatable with respect to said spinal cage, wherein said spin-plate comprises a blade and a shaft attached to or integral with said blade, said shaft engaging with said spinal cage at a first end of said shaft and at a second end of said shaft opposed to said first end of said shaft;

wherein said spin-plate comprises a first structure, and said spinal cage comprises a second structure, extending into said interior, said second structure being capable of interaction with said first structure;

wherein at least a first rotational position of said spin-plate relative to said spinal cage, said first structure and said second structure are positioned relative to one another such that a first amount of torque, resulting from said interaction of said first structure and said second structure, is required to rotate said spin-plate relative to said spinal cage;

wherein at least a second rotational position of said spin-plate relative to said spinal cage, said first structure and said second structure are positioned relative to one another such that a second amount of torque, resulting from said interaction of said first structure and said second structure, is required to rotate said spin-plate relative to said spinal cage; and

wherein said first amount of torque is different from said second amount of torque.

2. The spinal cage assembly of claim 1 , wherein said first structure and said second structure are positioned at said first rotational position with respect to each other at an undeployed configuration of said spin-plate.

3. The spinal cage assembly of claim 1 , wherein said first structure and said second structure are positioned at said second rotational position with respect to each other at a fully-deployed configuration of said spin-plate.

4. The spinal cage assembly of claim 3 , wherein in said fully-deployed configuration, said blade is substantially parallel to a longitudinal direction of said spinal cage.

5. The spinal cage assembly of claim 1 , wherein said first amount of torque is greater than said second amount of torque.

6. A spinal cage assembly, comprising:

a spinal cage comprising a structure suitable to maintain two vertebrae separate from each other and having an interior having at least some empty space, and comprising a post protruding from said spinal cage into said interior, said post comprising a longitudinal axis and being fixedly attached to said spinal cage; and

a spin-plate comprising an axis of rotation and being engageable with said spinal cage, said spin-plate interacting with said post at a first set of one or more angular positions of said spin-plate relative to said spinal cage, said spin-plate not interacting with said post at a second set of one or more angular positions of said spin-plate relative to said spinal cage; and

wherein said longitudinal axis of said post is generally parallel with said axis of rotation of said spin-plate and is offset from said axis of rotation of said spin-plate.

7. The spinal cage assembly of claim 6 , wherein said spin-plate comprises a disc that interacts with said post.

8. The spinal cage assembly of claim 7 , wherein said disc comprises a tapered edge.

9. The spinal cage assembly of claim 7 , wherein said post has a frustoconical head.

10. The spinal cage assembly of claim 6 , wherein said spinal cage comprises a wall extending vertically and generally parallel to a vertical axis of said spinal cage and progressing circumferentially, wherein said wall forms a closed circumference fitting within an intervertebral disc space.

11. The spinal cage assembly of claim 6 , wherein a first torque amount due to interaction between said spin-plate and said post is required to rotate said spin-plate relative to said spinal cage when said spin-plate is at said first set of one or more angular positions; and

wherein a second torque amount due to said interaction between said spin-plate and said post is required to rotate said spin-plate relative to said spinal cage when said spin-plate is at said second set of one or more angular positions.

12. The spinal cage assembly of claim 11 , wherein said first torque amount is greater than said second torque amount.

13. A spinal cage assembly, comprising:

a spinal cage comprising a support structure suitable to maintain two vertebrae separate from each other and having an interior having at least some empty space; and

a spin-plate engaged with said spinal cage and rotatable with respect to said spinal cage, wherein said spin-plate comprises a blade and a shaft attached to said blade, said spin-plate having a rotational axis, and said shaft engaging with said spinal cage at a first end of said shaft and at a second end of said shaft opposed to said first end of said shaft;

wherein said spin-plate comprises a first structure having a circumference in which some points are at a greater radial distance from said rotational axis and some other points are at a lesser radial distance from said rotational axis, and said spinal cage comprises a second structure extending into said interior, said second structure being capable of interaction with said first structure;

wherein, at least a first set of one or more rotational positions of said spin-plate relative to said spinal cage, said first structure and said second structure are positioned relative to one another such that relative rotation of said spin-plate relative to said spinal cage is permitted and a first amount of torque resulting from said interaction of said first structure and said second structure is required to rotate said spin-plate relative to said spinal cage;

wherein at least a second set of one or more rotational positions of said spin-plate relative to said spinal cage, said first structure and said second structure are positioned relative to one another such that relative rotation of said spin-plate relative to said spinal cage is permitted and a second amount of torque resulting from said interaction of said first structure and said second structure is required to rotate said spin-plate relative to said spinal cage; and

wherein said first amount of torque is different from said second amount of torque.

14. A spinal cage assembly, comprising:

a spinal cage comprising a structure suitable to maintain two vertebrae separate from each other and having an interior having at least some empty space, and comprising a post protruding from said spinal cage into said interior; and

a spin-plate comprising a first tapered side surface and an axis of rotation, said spin-plate being mateable to said spinal cage;

wherein said post comprises a second tapered side surface, said post being located away from said axis of rotation of said spin-plate;

wherein said spin-plate interacts with a surface of said post so as to restrict motion of said spin-plate with respect to said spinal cage, wherein said first tapered side surface is tapered in a direction corresponding to said second tapered side surface; and

wherein said post has a longitudinal axis that is generally parallel to said axis of rotation of said spin-plate.

15. A spinal cage assembly, comprising:

a spinal cage comprising a structure suitable to maintain two vertebrae separate from each other and having an interior having at least some empty space, and comprising a post protruding from said spinal cage into said interior; and

a spin-plate comprising a first tapered side surface and an axis of rotation, said spin-plate being mateable to said spinal cage;

wherein said post comprises a second tapered side surface, said post being located away from said axis of rotation of said spin-plate;

wherein said spin-plate interacts with a surface of said post so as to restrict motion of said spin-plate with respect to said spinal cage, wherein said first tapered side surface is tapered in a direction corresponding to said second tapered side surface; and

wherein said post has a generally frustoconical geometry.

16. A spinal cage assembly, comprising:

a spinal cage comprising a support structure suitable to maintain two vertebrae separate from each other and having an interior having at least some empty space; and

a spin-plate engaged with said spinal cage and rotatable with respect to said spinal cage;

wherein said spin-plate is provided with a first structure and said spinal cage is provided with at least one second structure that is capable of interaction with said first structure;

wherein said spin-plate and said spinal cage define a stowed configuration in which said spin-plate is entirely contained within said interior of said spinal cage, and said spin-plate and said spinal cage define a deployed configuration in which a part of said spin-plate extends outside an envelope of said spinal cage, said spin-plate and said spinal cage also define an intermediate configuration between said stowed configuration and said deployed configuration;

wherein, in said stowed configuration, said interaction of said first structure and said at least one second structure releasably retains said spin-plate against rotation such that a nonzero first threshold torque, resulting from said interaction of said first structure and said at least one second structure, is required to rotate said spin-plate out of said stowed configuration toward said deployed configuration;

wherein, in said intermediate configuration, a second torque resulting from said interaction of said first structure and said at least one second structure is required to rotate said spin-plate toward said deployed configuration; and

wherein said nonzero first threshold torque is greater than said second torque.