US Patent 8435302 Instruments and interbody spinal implants enhancing disc space distraction

An apparatus for distracting a disc space having an annulus. The apparatus includes a spinal implant having a pre-determined size sufficient to balance frictional fit in the disc space and elongation of the annulus. The implant has a top surface, a bottom surface, opposing lateral sides, and opposing anterior and posterior portions defining a substantially hollow center and a single vertical aperture. At least one of the opposing anterior and posterior portions presents a substantially flat impact face including an opening with an instrument retention feature. The apparatus also includes a rasp, a plurality of distractors, and an instrument able to engage and manipulate the spinal implant, the rasp, and the plurality of distractors. The size-specific rasp is adapted to clear the disc space of all soft tissue and cartilage. The plurality of distractors have progressively increasing heights adapted to distract the disc space before use of the spinal implant.