Surgical guidance system and method

Abstract

A method of generating resection data for use in planning an arthroplasty procedure on a patient bone covered at least partially in cartilage includes receiving a three-dimensional patient bone model comprising a bone model surface, and correlated with a position and orientation of the patient bone via a navigation system. The method further includes identifying a target region on the bone model surface of the model for intra-operative registration, and receiving location data for a first plurality of points based on the intra-operative registration of the cartilage on the patient bone in locations corresponding to points within the target region on the bone model surface. The method further includes determining resection depth based at least in part on the location data for the first plurality of points; and generating resection data using the resection depth, the resection data configured to be utilized by the navigation system during the arthroplasty procedure.

What is claimed is: 
     
         1 . A method of generating resection data, by a computer, for use in planning an arthroplasty procedure on a patient bone covered at least partially in cartilage, the method comprising:
 receiving, by the computer, a three-dimensional patient bone model comprising a bone model surface, the three-dimensional patient bone model correlated with a position and orientation of the patient bone via a navigation system, the three-dimensional patient bone model in a three-dimensional coordinate system;   identifying, by the computer, a target region on the bone model surface of the three-dimensional patient bone model for intra-operative registration;   receiving, by the computer, location data for a first plurality of points based on the intra-operative registration of the cartilage on the patient bone in locations corresponding to points within the target region on the bone model surface of the three-dimensional bone model;   determining, by the computer, a resection depth based at least in part on the location data for the first plurality of points; and   generating, by the computer, resection data using the resection depth, the resection data configured to be utilized by the navigation system during the arthroplasty procedure.   
     
     
         2 . The method of  claim 1 , further comprising mapping, by the computer, the location data for the first plurality of points into the three-dimensional coordinate system. 
     
     
         3 . The method of  claim 1 , wherein determining the resection depth comprises determining a depth difference between the first plurality of points and the target region on the bone model surface. 
     
     
         4 . The method of  claim 3 , further comprising determining, by the computer, the resection depth by adding the depth difference to a bone-only resection depth. 
     
     
         5 . The method of  claim 4 , wherein the bone-only resection depth is adjusted distally by the addition of the depth difference. 
     
     
         6 . The method of  claim 1 , wherein determining the resection depth comprises altering a bone-only resection depth based on the first plurality of points. 
     
     
         7 . The method of  claim 6 , wherein the bone-only resection depth is adjusted distally based on the first plurality of points. 
     
     
         8 . The method of  claim 1 , wherein the patient bone includes a femur and the three-dimensional patient bone model includes a three-dimensional patient femur model. 
     
     
         9 . The method of  claim 8 , wherein the target region comprises an articular area of at least one of a medial or lateral condyle of the three-dimensional patient femur model. 
     
     
         10 . The method of  claim 1 , wherein the patient bone includes a tibia and the three-dimensional patient bone model includes a three-dimensional patient tibia model. 
     
     
         11 . The method of  claim 10 , wherein the resection depth comprises a proximal resection depth of the tibia, wherein the proximal resection depth is adjusted proximally based on the location data for the first plurality of points. 
     
     
         12 . The method of  claim 10 , wherein the target region comprises an articular area of at least one of a medial or lateral tibial plateau of the three-dimensional patient tibia model. 
     
     
         13 . The method of  claim 1 , wherein the three-dimensional patient bone model is a bone only model. 
     
     
         14 . The method of  claim 1 , wherein the three-dimensional patient bone model is generated from medical images of the patient bone. 
     
     
         15 . The method of  claim 1 , wherein the navigation system operates in conjunction with an autonomous robot or a surgeon-assisted device in performing the arthroplasty procedure.