Force measuring joint distraction lever

A system, comprising:

• a joint distractor configured to apply a distraction force to distract a joint;
• and
• an optical tracking system configured to track relative poses of the joint distractor, a first bone of the joint, and a second bone of the joint;
• and
• a computing system programmed to:
• receive information indicating the relative poses of the joint distractor, the first bone of the joint, and the second bone of the joint;
• determine, using the relative poses of the joint distractor and at least one of the first bone of the joint or the second bone of the joint, an amount of the distraction force off of an axis of the joint;
• and
• cause, using the amount of the distraction force off of an axis of the joint, an adjustment of direction of the distraction force.

A system, comprising:

• a joint distractor configured to apply a distraction force to distract a joint;
• a tracking system configured to track relative poses of the joint distractor and a first bone of the joint in contact with the joint distractor;
• and
• a computing system programmed to:
• receive information indicating the relative poses of the joint distractor and the first bone of the joint;
• determine, using the relative poses of the joint distractor and the first bone of the joint, an amount of the distraction force off of a mechanical axis of the first bone;
• and
• cause, using the amount, an adjustment of a distraction the distraction force.