Patent ID: 6955691

Claim:
An expandable interfusion cage, comprising a cage body including a seat part provided with an orifice and a branch part defining an inside space and having a plurality of elongate branches formed at their proximal ends integrally with said seat part, with each two of said adjoining branches defining therebetween an opening which communicates with said inside space, said branch part having a guiding slit communicating with said opening and defined between each two of said adjoining branches when viewed on distal end surfaces of said branches, so that four said guiding slits are formed and cooperate to create a cross-shaped space; and a spacer movably arranged in said inside space of said cage body and having a substantially cylindrical spacer body with a head portion which is formed as a cross-shaped protrusion biasing said branches radially outwardly, and a base portion formed as a disc with a diameter larger than a diameter of said head portion and having a pair of guide pieces oppositely formed at both sides of said disc and engaging in said guiding slits.