Expandable fusion device for positioning between adjacent vertebral bodies

An intervertebral implant comprising:

• a first expansion wedge;
• a second expansion wedge;
• an upper body engaged with the first expansion wedge and the second expansion wedge comprising:
• an inferior surface;
• a superior surface;
• and
• an upper body through hole;
• wherein an overall size of the upper body through hole increases as the first expansion wedge and the second expansion wedge move in opposite directions relative to each other;
• and
• a lower body engaged with the first expansion wedge and the second expansion wedge.

An intervertebral implant comprising:

• a first substantially pyramidal-shaped wedge having:
• a first pair of laterally extending flanges;
• and
• a second pair of laterally extending flanges spaced from the first pair of laterally extending flanges;
• an upper body comprising:
• an inferior surface, a superior surface, and a pair of recessed tracks for receiving the first pair of laterally extending flanges;
• a lower body comprising:
• a superior surface, an inferior surface, and a pair of recessed tracks for receiving the second pair of laterally extending flanges;
• wherein the first substantially pyramidal-shaped wedge is movable between a first position and a second position within the recessed tracks of the upper body and the lower body;
• and
• a case housing the first substantially pyramidal-shaped wedge;
• wherein the upper body includes a secondary pair of the recessed tracks axially spaced from the pair of recessed tracks along a longitudinal length of the upper body;
• and
• wherein one of the pairs of the recessed tracks of the upper body extends parallel to one of the pairs of the recessed tracks of the lower body.