An expandable spinal fusion device comprising: an elongated cam having a plate body extending along a longitudinal axis; a first elongated plate comprising a first proximal end, a first distal end, a first exterior surface, and a first interior surface opposite the first exterior surface, at least a portion of the first interior surface being in physical contact with the plate body of the elongated cam, wherein at least a portion of the first exterior surface is sized and shaped to interface with a first vertebral body; a second elongated plate comprising a second proximal end, a second distal end, a second exterior surface, and a second interior surface opposite the second exterior surface, at least a portion of the second interior surface being in physical contact with the plate body of the elongated cam, wherein at least a portion of the second exterior surface is sized and shaped to interface with a second vertebral body; wherein the elongated cam is adapted to cause the first and second elongated plates to move away from each other upon the elongated cam being rotated about the longitudinal axis such that a relative orientation of the first and second elongated plates is changed from a collapsed orientation to at least one expanded orientation; and a locking mechanism, separate from the elongated cam, that is adapted to maintain the relative orientation of first and second elongated plates in the at least one expanded orientation characterised in that the elongated cam is removable from the expandable spinal fusion device without causing the first and second elongated plates to return to the collapsed orientation. an elongated cam having a plate body extending along a longitudinal axis; a first elongated plate comprising a first proximal end, a first distal end, a first exterior surface, and a first interior surface opposite the first exterior surface, at least a portion of the first interior surface being in physical contact with the plate body of the elongated cam, wherein at least a portion of the first exterior surface is sized and shaped to interface with a first vertebral body; a second elongated plate comprising a second proximal end, a second distal end, a second exterior surface, and a second interior surface opposite the second exterior surface, at least a portion of the second interior surface being in physical contact with the plate body of the elongated cam, wherein at least a portion of the second exterior surface is sized and shaped to interface with a second vertebral body; wherein the elongated cam is adapted to cause the first and second elongated plates to move away from each other upon the elongated cam being rotated about the longitudinal axis such that a relative orientation of the first and second elongated plates is changed from a collapsed orientation to at least one expanded orientation; and a locking mechanism, separate from the elongated cam, that is adapted to maintain the relative orientation of first and second elongated plates in the at least one expanded orientation characterised in that the elongated cam is removable from the expandable spinal fusion device without causing the first and second elongated plates to return to the collapsed orientation.