Orthopedic fixation with imagery analysis

Abstract

Methods of orthopedic fixation and imagery analysis are provided. Images of first and second bone segments attached to a fixation apparatus are captured. Fixator elements identified in the images can be used to obtain imaging scene parameters. Bone elements identified in the images can be used with the imaging scene parameters to reconstruct a three dimensional representation of positions and/or orientations of the first and second bone segments with respect to the fixation apparatus.

What is claimed: 
     
         1 . A method of orthopedic fixation, the method comprising:
 attaching a fixation apparatus to a first bone segment and a second bone segment;   capturing a first image of the fixation apparatus, the first bone segment, and the second bone segment from a first orientation with respect to the fixation apparatus;   capturing a second image of the fixation apparatus, the first bone segment, and the second bone segment from a second orientation with respect to the fixation apparatus that is different from the first orientation;   computing a first transformation matrix and a second transformation matrix for the first image and the second image, respectively, using identified respective locations of a plurality of fixator elements in the first image and the second image; and   utilizing the first transformation matrix and the second transformation matrix to reconstruct a three dimensional representation of the first bone segment and the second bone segment with respect to the fixation apparatus.   
     
     
         2 . The method of  claim 1 , wherein the first orientation and the second orientation are non-orthogonal with respect to each other. 
     
     
         3 . The method of  claim 1 , wherein the fixation apparatus comprises a distraction osteogenesis ring system, a hexapod, or a Taylor spatial frame. 
     
     
         4 . The method of  claim 1 , wherein at least one additional image is captured, and a respective transformation matrix is calculated for each at least one additional image. 
     
     
         5 . The method of  claim 1 , wherein the first transformation matrix is computed based at least in part upon comparing a location of a first fixator element in the first image with a corresponding location of the first fixator element in three dimensional space, and wherein the second transformation matrix is computed based at least in part upon comparing a location of a selected fixator element in the second image with a corresponding location of the second fixator element in three dimensional space. 
     
     
         6 . The method of  claim 1 , wherein the first transformation matrix and the second transformation matrix are decomposed, respectively, into a first plurality of imaging scene parameters and second plurality of imaging scene parameters. 
     
     
         7 . The method of  claim 6 , wherein the three dimensional representation is reconstructed using the first plurality of imaging scene parameters, the second plurality of imaging scene parameters, respective locations of a first plurality of bone elements in the first image, and respective locations of a second plurality of bone elements in the second image. 
     
     
         8 . The method of  claim 7 , wherein each of the first plurality of bone elements and the second plurality of bone elements comprises at least one anatomical feature of the first bone segment and at least one anatomical feature of the second bone segment. 
     
     
         9 . The method of  claim 1 , wherein the first transformation matrix and the second transformation matrix are constructed based, at least in part, on one or more lines representing one or more of the plurality of fixator elements. 
     
     
         10 . The method of  claim 9 , wherein the computing of the first transformation matrix and the second transformation matrix comprises constructing rows of matrices based on the one or more lines. 
     
     
         11 . The method of  claim 9 , comprising computing of the first transformation matrix and the second transformation matrix based, at least in part, on a point value and a gradient value for each of the one or more lines. 
     
     
         12 . The method of  claim 9 , wherein the one or more lines represent center lines of one or more struts. 
     
     
         13 . The method of  claim 1 , wherein at least one of the plurality of fixator elements comprises a radio-opaque marker element. 
     
     
         14 . A method of manipulating objects, the method comprising:
 attaching a manipulation apparatus to a first object and a second object;   capturing a first image of the manipulation apparatus, the first object, and the second object from a first orientation;   capturing a second image of the manipulation apparatus, the first object, and the second object from a second orientation;   identifying respective representations of a plurality of manipulation apparatus components in the first image and the second image;   utilizing locations of the respective representations to compute a first transformation matrix and a second transformation matrix for the first image and the second image, respectively;   decomposing the first transformation matrix and the second transformation matrix into a first plurality of imaging scene parameters and a second plurality of imaging scene parameters, respectively;   reconstructing a three dimensional representation of the first object and the second object with respect to the manipulation apparatus;   calculating geometry changes for the manipulation apparatus, the geometry changes representing a repositioning of the first object and the second object with respect to each other; and   implementing the geometry changes in order to reposition the first object and the second object with respect to each other.   
     
     
         15 . The method of  claim 14 , wherein the three dimensional representation is reconstructed using the first plurality of imaging scene parameters, the second plurality of imaging scene parameters, a location of an element of at least one of the objects in the first image, and a location of an element of at least one of the objects in the second image. 
     
     
         16 . The method of  claim 14 , wherein the first transformation matrix and the second transformation matrix are computed based, at least in part, on one or more lines representing one or more of the plurality of manipulation apparatus components. 
     
     
         17 . The method of  claim 16 , wherein computing of the first transformation matrix and the second transformation matrix comprises constructing rows of matrices based on the one or more lines. 
     
     
         18 . The method of  claim 16 , wherein computing of the first transformation matrix and the second transformation matrix is based, at least in part, on a point value and a gradient value for each of the one or more lines. 
     
     
         19 . The method of  claim 16 , wherein the one or more lines represent center lines of one or more struts. 
     
     
         20 . The method of  claim 14 , wherein the manipulation apparatus comprises a distraction osteogenesis ring system, a hexapod, or a Taylor spatial frame.