Patent ID: 7776046

Claim:
A method of distracting adjacent vertebrae, comprising: providing a distraction head having a longitudinal axis, the distraction head including: a first pair of opposite surfaces that extend substantially along the longitudinal axis, the first pair of opposite surfaces defining a first working distraction height approximating a first disc space height between the adjacent vertebrae; a second pair of opposite surfaces extending substantially along the longitudinal axis and defining a second working distraction height approximating a second disc space height between the adjacent vertebrae, with the first working distraction height being different from the second working distraction height; a rounded leading edge extending between the second pair of opposite surfaces to facilitate insertion between the adjacent vertebrae to directly distract the adjacent vertebrae to the second disc space height; and a pair of oppositely facing inclined surfaces extending from the rounded leading edge and blending into said first pair of oppositely facing surfaces; defining the first disc space height between the adjacent vertebrae by spreading the adjacent vertebrae apart by engaging the pair of inclined surfaces with the adjacent vertebrae and supporting the adjacent vertebrae with the first pair of opposite surfaces; and rotating the distraction head about the longitudinal axis to define the second disc space height between the adjacent vertebrae by supporting the adjacent vertebrae with the second pair of opposite surfaces, with the first disc space height being different from the second disc space height.