Patent ID: 8663233

Claim:
A boring instrument guiding device which is configured to guide a boring instrument that forms a pilot hole for embedding a pedicle screw in a vertebral pedicle of the third cervical vertebra to the seventh cervical vertebra, said device comprising: a reference pin having a tip position and a proximal end side, and being configured to be used as a reference by being inserted into a base of the vertebral pedicle from a rear to a front of a spine; and an arm extending sideward from said proximal end side of said reference pin, wherein said reference pin has a length that enables said tip position of said reference pin to reach the base of the vertebral pedicle, and is completely straight, wherein said reference pin includes a step portion, said step portion being defined, in the longitudinal direction of said reference pin, by a diameter difference between a large diameter section of said reference pin and a small diameter section of said reference pin, said large diameter section extending from said step portion to said proximal end of said reference pin, said small diameter section extending from said step portion to said tip of said reference pin and having the same length as a target insertion depth, and said step portion being configured and arranged so as to be capable of being a stopper that engages the surface of the vertebral arch, and wherein said arm includes a plurality of guide holes, each guide hole of said plurality of guide holes being opened toward said tip position of said reference pin to guide said boring instrument, said plurality of guide holes being disposed in said arm in a radial pattern centered at said tip position of said reference pin.