Video-based navigation for guiding a tool towards a target

A method for controlling a surgical navigation system, the method comprising:

• receiving one or more images of a surgical environment;
• determining a plurality of points on patient anatomy indicated by an instrument identified in the surgical environment;
• defining a bounding plane on the patient anatomy based on the plurality of points;
• and
• generating, for display, visual guidance based on the bounding plane and a location of the instrument, wherein the visual guidance includes (i) at least one constraint for a location of a tunnel to be formed in the patient anatomy, (ii) a visual indicator of the location of the tunnel based on the location of the instrument, and (iii) an indication of whether the location of the tunnel satisfies the at least one constraint.

A surgical navigation system, comprising:

• an image capture device configured to capture one or more images of a surgical environment;
• and
• a controller configured to
• detect a location of an instrument within the surgical environment using the one or more images and one or more fiducial markers on the instrument,
• identify a plurality of points on patient anatomy based on respective locations of the instrument within the surgical environment,
• define a bounding plane on the patient anatomy based on the plurality of points, and
• generate, for display, visual guidance based on the bounding plane and the location of the instrument, wherein the visual guidance includes (i) at least one constraint for a location of a tunnel to be formed in the patient anatomy, (ii) a visual indicator of the location of the tunnel based on the location of the instrument, and (iii) an indication of whether the location of the tunnel satisfies the at least one constraint,
• wherein the at least one constraint includes at least one of
• a distance from an edge of the tunnel to a back wall of a lateral femoral condyle, and
• a distance percentage along an axis defined by a posterior reference point on the lateral femoral condyle and an anterior-most point of a condylar wall.