Laminoplasty Plates and Methods of Expanding the Spinal Canal

Abstract

A method of expanding the spinal canal of a vertebra including inserting a bone anchor into a first lamina of the vertebra, cutting completely through the first lamina to create a space in the first lamina, cutting partially through a second, contra-lateral lamina of the vertebra to create a partial cut in the second lamina, engaging a first segment of a plate with the bone anchor, pivoting the bone anchor and the first lamina about the partial cut in the second lamina to increase the extent of the space in the first lamina, and connecting a second segment of the plate to a portion of the vertebra across the space from the first segment of the plate such that the plate spans the space and stabilizes the vertebra.

1 . A laminoplasty plate comprising:
 first plate segment including a pair of spaced apart arms defining a slot that opens at a first end of the plate,   a second plate segment including a first hole for receiving a bone anchor, a central longitudinal axis of the plate extending from the first segment of the plate to the second segment of the plate,   a central plate segment interposed between the first plate segment and the second plate segment, the first plate segment and the second plate segment lying in separate approximately parallel planes and the central plate segment connecting the first plate segment and the second plate segment and lying in a plane that intersects the parallel planes.   
     
     
         2 . The laminoplasty plate of  claim 1 , wherein the first plate segment includes a first hole for receiving a bone anchor. 
     
     
         3 . The laminoplasty plate of  claim 2 , wherein the first hole in the first plate segment has a center that lies on the central longitudinal axis of the plate. 
     
     
         4 . The laminoplasty plate of  claim 2 , wherein the second plate segment includes a second hole and the first hole and the second hole are aligned along the central longitudinal axis of the plate. 
     
     
         5 . The laminoplasty plate of  claim 2 , wherein the second plate segment includes a third hole and the second hole and the third hole are aligned along an axis transverse to the central longitudinal axis. 
     
     
         6 . The laminoplasty plate of  claim 1 , wherein the central plate segment includes an opening for receiving an anchor to connect to a bone graft. 
     
     
         7 . The laminoplasty plate of  claim 6 , wherein the opening in the central plate segment is an elongated slot having a slot axis that is coincident with the central longitudinal axis of the plate. 
     
     
         8 . The laminoplasty plate of  claim 1 , wherein the slot in the first plate segment has a slot axis that is coincident with the central longitudinal axis of the plate. 
     
     
         9 . A laminoplasty plate comprising:
 first plate segment including a pair of spaced apart arms defining a slot that opens at a first end of the plate,   a second plate segment including a second hole for receiving a bone anchor and a third hole for receiving a bone anchor, a central longitudinal axis of the plate extending from the first segment of the plate to the second segment of the plate, the slot in the first plate segment having a slot axis that is coincident with the central longitudinal axis of the plate, the first plate segment including a first hole for receiving a bone anchor, the first hole, the second hole, and the third hole each having a center that lies on the central longitudinal axis of the plate, and   a central plate segment interposed between the first plate segment and the second plate segment, the first plate segment and the second plate segment lying in separate approximately parallel planes and the central plate segment connecting the first plate segment and the second plate segment and lying in a plane that intersects the parallel planes.   
     
     
         10 . The laminoplasty plate of  claim 9 , wherein the central plate segment includes an opening for receiving an anchor to connect to a bone graft. 
     
     
         11 . The laminoplasty plate of  claim 10 , wherein the opening in the central plate segment is an elongated slot having a slot axis that is coincident with the central longitudinal axis of the plate. 
     
     
         12 . A laminoplasty plate comprising:
 first plate segment including a pair of spaced apart arms defining a slot that opens at a first end of the plate,   a second plate segment including a second hole for receiving a bone anchor and a third hole for receiving a bone anchor, a central longitudinal axis of the plate extending from the first segment of the plate to the second segment of the plate, the slot in the first plate segment having a slot axis that is coincident with the central longitudinal axis of the plate, the first plate segment including a first hole for receiving a bone anchor, the first hole in the first plate segment having a center that lies on the central longitudinal axis of the plate, the second hole and the third hole each having a center that lies on an axis that is perpendicular to the central longitudinal axis of the plate, and   a central plate segment interposed between the first plate segment and the second plate segment, the first plate segment and the second plate segment lying in separate approximately parallel planes and the central plate segment connecting the first plate segment and the second plate segment and lying in a plane that intersects the parallel planes.   
     
     
         13 . The laminoplasty plate of  claim 12 , wherein the central plate segment includes an opening for receiving an anchor to connect to a bone graft. 
     
     
         14 . The laminoplasty plate of  claim 13 , wherein the opening in the central plate segment is an elongated slot having a slot axis that is coincident with the longitudinal axis of the plate.