Instrumentation for creating an intervertebral space for receiving an implant

#1. Field of the Invention

#This invention relates generally to intervertebral spinal surgery, and more particularly to surgical instrumentation and to a method for creating one or more spaces between adjacent vertebral bodies in which the space has a shape and vertebral surfaces adapted in size to receive an implant or implants to be implanted in the space, and the method of implanting those implants.

#2. Description of the Prior Art

#The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate preferred embodiments of the invention. Together with the description, they serve to explain the objects, advantages and principles of the invention. In the drawings:

#FIG. 1 is a leading end side perspective view of a midline spinal marker of the present invention;

#FIG. 2 is a leading end view of the midline spinal marker of FIG. 1;

#Reference will now be made in detail to the present preferred embodiment of the invention, as illustrated in the accompanying drawings.

#FIGS. 1-28 are generally directed to an embodiment of an instrument set having a rectangular cross-section for use in spinal surgery for forming a substantially quadrilateral space in the spine. FIGS. 34-41 are generally directed to another embodiment of the present invention surgical instrument set having a circular cross-section for forming a substantially quadrilateral space in the spine. FIGS. 29, 29A, 32, 33, and 42-48 generally show the space formed in the spine by the instrument sets of FIGS. 1-28 and 34-41 with implants for placement in the created space. FIGS. 49-51 generally show an implant and vise adapted to hold the implant for loading the implant with fusion promoting substances. An instrument set for use in spinal surgery is used to form a substantially quadrilateral space in the spine for implanting a spinal implant into a disc space between adjacent vertebral bodies.

#The anterior aspect (front) of the spine may be exposed either by opening a surgical incision large enough to allow direct visualization or laproscopically with a small opening to allow instruments to be placed through the body from outside the body for visualization through an endoscope. The vertebral midline, which bisects the vertebral bodies along the longitudinal axis of the spinal column separating left from right is identified by the surgeon. As shown in FIGS. 1-4, an exemplary embodiment of a midline marker 100 of the present invention preferably is used to create reference marks at the vertebral midline on the disc material and on the adjacent vertebral bodies in a segment of the spine. Marker 100 has a shaft 102 terminating in an insertion tip 104 having a tapered leading edge 106 allowing it to be placed into a multitude of discs having various heights. Tapered leading edge 106 facilitates the insertion of marker 100 into the disc material contained in the disc space between two adjacent vertebral bodies. The juncture of shaft 102 and insertion tip 104 of marker 100 forms a shoulder 108 for butting against the anterior aspect of the adjacent vertebral bodies and thus prevents unwanted over penetration of insertion tip 104 into the disc space. Also located at shoulder 108 at the anterior aspect of shaft 102 are a plurality of dye exit holes 110. Dye exit holes 110 are in communication via a passage 112 with a syringe engaging well 114 located at a trailing end or proximal end 116 of shaft 102. Well 114 is adapted to receive the tip of a syringe (not shown), or any other well-known device for containing and injecting a dye into marker 100. A preferred marker 100 has advantages over a needle due at least in part to having a shoulder for preventing over penetration of the disc space or having the ability to provide multiple marks on the spine via multiple dye exit holes.