| abstract |
SUMMARY An osteogenic fusion device (10) between vertebral bodies having an integral central member (13) and opposing end portions (11,12) is provided. The end portions (11, 12) are dimensioned to maintain the height of the disc space (S). The central member (13) has a small diameter (D2) such that the osteogenic fusion device (10) forms an annular pocket (24) around the central member (13). A bone growth material (30) is located in an annular pocket (24) between the opposing end portions (11, 12). In one embodiment, the bone growth material (30) comprises a collagen sheet (30) soaked in a solution containing osteogenic fusion device forming protein (BMP). The osteogenic fusion device (10) is configured such that the bone growth material (30) is in direct contact with adjacent vertebrae (V1, V2). In addition to improving the contact area between the vertebrae (V1, V2) and the fusion material (30), the bone fusion device (10) reduces stress shielding to continuously assess fusion growth. And minimize the radiopacity of the implant. In another embodiment, the bone fusion device (10) has at least one end portion (12) with a truncated surface (21). The bone fusion device of the present invention may be combined with other fusion devices to form an implant device. The implantation device (140) has at least one support member (110) with a truncated surface (116), wherein the truncated surface (116) has other load bearing members, It is preferably configured to be combined with the load bearing bone growth device (10) of the present invention. The present invention also provides an implantable device (210) having adjacent load bearing members (211, 212) connected together to prevent lateral separation. Also described is a method of promoting osteointegrative growth in the void (S) between adjacent vertebrae (V1, V2) using the device of the present invention. |