Anterior spinal instrumentation and method for implantation and revision - Patent 6,139,551
A system and method for anterior fixation of the spine utilizes a cylindrical implant engaged in the intradiscal space at the cephalad and caudal ends of the construct. The implants are cylindrical fusion devices (10) filled with bone material to promote bone ingrowth and fusion of the disc space. An attachment member (40) is connected to each of the fusion devices (10) and a spinal rod (50) is connected to each of the attachment members using an eyebolt assembly (53, 54, 55). In a further inventive method, a revision of the construct is achieved by removing the fusion devices. Each fusion device is engaged by an elongated guide member (62) over which a cylindrical trephine (70) is advanced. The trephine (70) is used to extract a core (84) of bone material around the fusion implant, while the guide member (62) is used to remove the bone core (84) containing the fusion implant (10). In another aspect of the invention, a removal insert (90, 90') is provided that engages an implanted fusion device (10). The removal insert (90, 90') can be used to guide the trephine (70) around the fusion device, and is connected to a removal tool (100) once the bone core is created. The removal tool (100) includes a shaft (101) attached to the removal insert (90, 90'), and a slap hammer (104) slidably mounted on the shaft.