Externally threaded expandable orthopedic implant

1. An expandable screw for orthopedic insertion and expansion between a collapsed state and an expanded state, comprising:

an upper externally-threaded body segment;

a lower externally-threaded body segment opposite the upper externally-threaded body segment; and

an expansion member extending along a longitudinal axis thereof, connecting the upper externally-threaded body segment to the lower externally-threaded body segment, and configured, during the expansion between the collapsed state and the expanded state, to separate the upper externally-threaded body segment from the lower externally-threaded body segment,

wherein threads of the upper externally-threaded body segment and the lower externally-threaded body segment disposed on outer peripheral sections of the upper externally-threaded body segment and the lower externally-threaded body segment are configured to secure the screw to a bone segment of a patient,

wherein at least one of the upper externally-threaded body segment and the lower externally-threaded body segment has an elongated aperture extending in a longitudinal direction and cutting through multiple turns of the threads, and

wherein the expansion member expands the upper externally-threaded body segment from the lower externally-threaded body segment while the upper externally-threaded body segment and the lower externally-threaded body segment remain in a fixed orientation relative to each other.

2. The screw of claim 1 , wherein the expansion member expands the upper externally-threaded body segment from the lower externally-threaded body segment in a single expansion direction.

3. The screw of claim 1 , wherein the expansion member expands the upper externally-threaded body segment from the lower externally-threaded body segment in a single expansion direction without a radial deflection of the upper externally-threaded body segment from the lower externally-threaded body segment.

4. The screw of claim 1 , wherein at least one of the upper externally-threaded body segment and the lower externally-threaded body segment comprises an elongated body having an aperture.

5. The screw of claim 1 , wherein at least one of the outer peripheral sections of one of the upper externally-threaded body segment and the lower externally-threaded body segment comprises a partially cylindrical shell.

6. The screw of claim 1 , wherein at least one of the upper externally-threaded body segment and the lower externally-threaded body segment comprises an elongated body having a partially cylindrical shape.

7. The screw of claim 1 , wherein the expansion member comprises:

a wedge member connecting the upper externally-threaded body segment to the lower externally-threaded body segment;

a nose member having a distal end and a proximal end opposite the distal end, the nose member slidably connected to the upper externally-threaded body segment and the lower externally-threaded body segment; and

an actuator disposed between the nose member and the wedge member, for translation of the wedge member along a longitudinal axis of the screw.

8. The screw of claim 7 , wherein:

the actuator, on a first side, is slidably connected to the nose member and, on a second side, is connected to the wedge member; and

translation of the wedge member relative to the upper externally-threaded body segment and the lower externally-threaded body segment displaces the upper externally-threaded body segment and the lower externally-threaded body segment away from each other, thereby expanding the upper externally-threaded body segment away from the lower externally-threaded body segment.

9. The screw of claim 7 , wherein the expansion member further comprises:

a pin coupling the actuator to the nose member.

10. The screw of claim 9 , wherein the pin maintains a position of the nose member relative to the actuator once the screw has been assembled.

11. The screw of claim 7 , wherein the actuator is threadably connected to the wedge member such that rotating the actuator translates the wedge member along the longitudinal axis.

12. The screw of claim 7 , wherein the wedge member comprises a first wedge and a second wedge connected together by a rail.

13. The screw of claim 7 , wherein dovetail grooves on the wedge member hold and slidably connect the upper externally-threaded body segment and the lower externally-threaded body segment to the wedge member.

14. The screw of claim 1 , wherein, after expansion to the expanded state, plural windows for bone graft filling exist, wherein the plural windows comprise a first window between the upper externally-threaded body segment and the lower externally-threaded body segment and a second widow comprising the elongated aperture on at least one of the upper externally-threaded body segment and the lower externally-threaded body segment.

15. A system comprising the expandable screw of claim 1 , and an insertion tool which is configured to connect to the expandable screw for actuation and expansion of the expandable screw.

16. A method for utilizing an expandable screw for orthopedic insertion and expansion into a bone segment of a patient, the method comprising:

inserting the expandable screw of claim 1 into the bone segment of the patient; and

expanding the expandable screw.

17. An expandable screw for orthopedic insertion and expansion between a collapsed state and an expanded state, comprising:

an upper externally-threaded body segment;

a lower externally-threaded body segment opposite the upper externally-threaded body segment;

and

an expansion member extending along a longitudinal axis thereof, connecting the upper externally-threaded body segment to the lower externally-threaded body segment, and configured, during the expansion between the collapsed state and the expanded state, to separate the upper externally-threaded body segment from the lower externally-threaded body segment,

wherein threads of the upper externally-threaded body segment and the lower externally-threaded body segment disposed on outer peripheral sections of the upper externally-threaded body segment and the lower externally-threaded body segment are configured to secure the screw to a bone segment of a patient,

wherein at least one of the upper externally-threaded body segment and the lower externally-threaded body segment has an elongated aperture contained therewithin, extending in a longitudinal direction, and cutting through multiple turns of the threads, and

wherein the expansion member expands the upper externally-threaded body segment from the lower externally-threaded body segment in a single expansion direction without a radial deflection of the upper externally-threaded body segment from the lower externally-threaded body segment.

18. The screw of claim 17 , wherein the upper externally-threaded body segment has the elongated aperture contained therein and disposed opposite the lower externally-threaded body segment.

19. The screw of claim 17 , wherein the lower externally-threaded body segment has the elongated aperture contained therein and disposed opposite the upper externally-threaded body segment.