Aligning Vertebral Bodies

Abstract

Misaligned bones on opposite sides of a joint are aligned using a first rigid extension securable to one of the misaligned bones using a particular surgical approach, and a second rigid extension having a contacting surface positionable in contact with the other the two misaligned bones from the same surgical approach. The first and second rigid extensions are moved with respect to each other using a lever, whereby a pulling force is exerted on one of the bones, and a pushing force on the other, thereby aligning the first and second misaligned bones.

What is claimed is: 
     
         1 . A device for therapeutically aligning two misaligned bones on opposite sides of a joint, comprising:
 a first rigid extension securable to a first of the misaligned bones using a single approach selected from the group consisting of left lateral approach, right lateral approach, anterior approach, and posterior approach;   a second rigid extension having a contacting surface positionable in contact with the second of the two misaligned bones from the approach selected for securing said first rigid extension, said second rigid extension moveable with respect to said first rigid extension when said first rigid extension is secured to the first of the misaligned bones and said second rigid extension is positioned in contact with the second of the two misaligned bones; and   a lever configured to lever the first rigid extension with respect to the second rigid extension to move said first rigid extension with respect to said second rigid extension, to thereby exert a pulling force on the first of the two misaligned bones, and a pushing force on the second of the two misaligned bones, aligning the first and second misaligned bones.   
     
     
         2 . The device of  claim 1 , wherein the first and second misaligned bones are vertebrae. 
     
     
         3 . The device of  claim 2 , further including an intervertebral spacer, said first rigid extension securable to said intervertebral spacer, said intervertebral spacer connected to the first of the misaligned bones. 
     
     
         4 . The device of  claim 3 , wherein said intervertebral spacer is formed in two segments, each segment attachable to one of the first or second misaligned bones, said segments moveable with respect to each other when attached to a respective misaligned bone. 
     
     
         5 . The device of  claim 4 , said segments moveable in ratcheting engagement with respect to each other. 
     
     
         6 . The device of  claim 1 , wherein said lever applies leverage using a rotatable thread. 
     
     
         7 . The device of  claim 1 , wherein said first rigid extension is securable to the misaligned bone using a threaded fastener. 
     
     
         8 . The device of  claim 1 , wherein said first rigid extension is a plate. 
     
     
         9 . The device of  claim 8 , wherein said plate forms a levered connection between the first and second misaligned bones. 
     
     
         10 . The device of  claim 1 , wherein said first rigid extension extends around the first misaligned bone to contact a portion of the first misaligned bone which faces an approach different from the approach selected. 
     
     
         11 . The device of  claim 1 , wherein one of the first or second misaligned bones is the sacrum. 
     
     
         12 . The device of  claim 1 , wherein the lever is a screw having threads configured to engage bone on a first end, and threads configured to engage a nut on a second, opposite end, the nut rotated about said second end move said second rigid extension and to thereby lever the first and second misaligned bones into alignment. 
     
     
         13 . The device of  claim 1 , further including an intervertebral spacer. 
     
     
         14 . The device of  claim 13 , wherein said intervertebral spacer is expandable to increase a distance between the first and second misaligned bones. 
     
     
         15 . A device for therapeutically aligning two vertebrae, comprising:
 a first rigid extension securable to a first of the vertebrae using a single approach selected from the group consisting of left lateral approach, right lateral approach, anterior approach, and posterior approach;   a second rigid extension having a contacting surface positionable in contact with the second of the two vertebrae from the approach selected for securing said first rigid extension, said second rigid extension moveable with respect to said first rigid extension when said first rigid extension is secured to the first of the vertebrae and said second rigid extension is positioned in contact with the second of the two vertebrae;   a lever configured to lever the first rigid extension with respect to the second rigid extension to move said first rigid extension with respect to said second rigid extension, to thereby exert a pulling force on the first of the two vertebrae, and a pushing force on the second of the two vertebrae, aligning the first and second vertebrae; and   a fastener configured to maintain the first and second vertebrae in relative alignment.   
     
     
         16 . The device of  claim 15 , further including an intervertebral spacer connectable to at least one of the first and second rigid extensions during alignment of the vertebrae, and connectable to both vertebrae to maintain the vertebrae in relative alignment. 
     
     
         17 . The device of  claim 15 , the first rigid extension forming a first portion of an intervertebral spacer, the second rigid extension forming a second portion of an intervertebral spacer, the first and second portions mateably engageable and maintainable in relative mutual engagement using a ratchet. 
     
     
         18 . A method for therapeutically aligning two misaligned bones on opposite sides of a joint, comprising:
 securing a first rigid extension to a first of the misaligned bones using a single approach selected from the group consisting of left lateral approach, right lateral approach, anterior approach, and posterior approach;   contacting the second of the misaligned bones with a second rigid extension, the second rigid extension having a contacting surface positionable in contact with the second of the two misaligned bones from the approach selected for securing the first rigid extension, the second rigid extension moveable with respect to the first rigid extension when the first rigid extension is secured to the first of the misaligned bones and the second rigid extension is positioned in contact with the second of the two misaligned bones; and   levering the first rigid extension with respect to the second rigid extension using a lever configured to move the first rigid extension with respect to the second rigid extension, to thereby exert a pulling force on the first of the two misaligned bones, and a pushing force on the second of the two misaligned bones, aligning the first and second misaligned bones.   
     
     
         19 . The method of  claim 18 , further including inserting an intervertebral spacer between the two misaligned bones. 
     
     
         20 . The method of  claim 19 , further including:
 connecting the intervertebral spacer to the first of the misaligned bones; and   applying the lever between the intervertebral spacer and the second of the misaligned bones.