Robotic surgery

1. A method for performing spinal surgery, the method comprising:

exposing a vertebra of a patient;

disposing a distal end of a laser instrument proximate the vertebra;

conducting a laser-based topographical analysis of the vertebra using the laser instrument;

registering a patient's anatomy using the laser-based topographical analysis; and

creating a pilot hole in the vertebra with the laser instrument,

wherein creating a pilot hole in the vertebra with the laser instrument includes creating a multi-diameter pilot hole.

2. The method of claim 1 , further comprising:

determining that the patient's spine shifted since a prior non-laser-based registration; and

wherein the registering of the patient's anatomy includes:

updating an existing non-laser-based registration using the laser-based topographical analysis.

3. The method of claim 1 , wherein creating the multi-diameter pilot hole includes:

creating a multiple diameter pilot hole having a countersink diameter and a minor dimeter interference.

4. The method of claim 1 , further comprising:

placing a navigated instrument or an implant engaged with the navigated instrument into the pilot hole.

5. The method of claim 1 , further comprising:

conducting a spectral analysis of laser reflection received through the laser instrument to determine laser characteristics to be used to complete a surgical plan.

6. The method of claim 1 , further comprising:

registering a patient's anatomy using a non-laser registration technique to produce a non-laser registration;

conducting a laser-based topographical analysis of the vertebra; and

calculating a registration confidence value for the registration using the laser-based topographical analysis.

7. A method comprising:

identifying range of motion limits;

selecting a tip for a laser instrument based on an angulation of the tip and the range of motion limits; and

removing a portion of facet joint tissue of a of a facet of a vertebra using laser energy transmitted from a distal end of the tip of the laser instrument,

wherein the removing includes starting a laser cut on an outside of the facet and angling the transmission of the laser energy back into bone.

8. The method of claim 7 ,

wherein the laser instrument comprises an elongate shaft that defines a longitudinal axis;

wherein the laser instrument defines a laser pulse axis along which the laser instrument is configured to direct laser pulses; and

wherein the laser pulse axis is non-parallel with respect to the longitudinal axis.

9. The method of claim 7 , further comprising: using a tissue dilator to expose spine tissue.

10. The method of claim 7 , further comprising: using laser topography, laser reflection, laser refraction, or optical coherence tomography to confirm when a cut is complete.

11. The method of claim 7 , wherein starting the laser cut on an outside of the facet and angling the transmission of laser energy back into bone includes using a mirror or angled laser fiber to perform the angling.

12. The method of claim 7 , wherein starting the laser cut on an outside of the facet and angling the transmission of laser energy back into bone includes angling the transmission of laser energy in a direction other than toward a disc or nerve.

13. The method of claim 7 , further comprising: extending the laser cut to undermine a spinous process proximate the facet joint and continuing the laser cut along a contralateral foraminal recess.

14. The method of claim 7 , further comprising: checking for range of motion limits that may dictate a patient re-orientation.

15. The method of claim 7 , further comprising tuning a laser generator of the laser instrument such that generated laser pulses reach a frequency selected to cut a particular kind of tissue.

16. The method of claim 7 , further comprising tracking the removing through laser topography, reflected laser energy, refracted laser energy, or optical coherence tomography to determine removed areas.

17. A method comprising:

exposing a vertebra of a patient;

disposing a distal portion of a laser instrument proximate the vertebra; and

creating a pilot hole in the vertebra, wherein the creating of the pilot hole includes, while creating the pilot hole, repeatedly changing a direction of laser pulses emitted from the laser instrument.

18. The method of claim 17 , wherein changing the direction of the laser pulses emitted from the laser instrument includes:

changing an angle at which laser pulses leave the laser instrument by changing an angle of a light director of the laser instrument; or

changing an angle of a longitudinal axis of the laser instrument from a first angle to a second angle.

19. The method of claim 17 ,

wherein creating the pilot hole includes:

advancing the laser instrument toward the vertebra after removing a first amount of tissue from the vertebra and before removing a second amount of tissue from the vertebra; and

after creating the pilot hole, measuring an impedance related to tissue defining a bottom of the pilot hole to determine whether the tissue is bone.