Patent ID: 8496706

Claim:
A bone cage for controlled expansion comprised of: a contoured upper body member of a first selective height comprised of: a substantially convexly curved horizontal upper outer surface, a mating inner surface, a flexible spring tab, a contoured cam lift follower, at least one bone graft opening, and a cam lift bearing surface; a contoured lower body member of a second selective height comprised of: a substantially convexly curved horizontal lower outer surface, a mating inner surface, a flexible spring tab, a contoured cam lift follower, at least one bone graft opening, and a cam lift bearing surface; wherein said upper body member and said lower body member are discrete components and selectively and pivotally attached to each other at one end; wherein said upper body member and said lower body member have tapered distal ends and proximal ends rounded with a constant slope; wherein said mating surfaces are in physical contact with each other when in a closed position; and at least one cam lift for controlling pivotal movement of the contoured upper body member relative to the contoured lower body member from said closed position to an open position, wherein said cam lift is secured between said contoured upper body member and said contoured lower body member in both said closed position and said open position, said at least one cam lift comprised of: a distal end having a plurality of paired cam lift lobes alternated with a plurality of paired nesting surfaces, wherein said nesting surfaces are contoured to mate with said cam followers, a proximal end having a plurality of positional flats adapted to engage said spring tabs when said cam lift is rotated, and a cam lift shaft in physical rotational contact with said cam lift bearing surfaces.