Vertebral body replacement

Abstract

This invention concerns a vertebral body replacement element to be inserted into an intervertebral space, thus supporting the spinal column of a patient. The vertebral body replacement element has a hollow upper member and a hollow lower member, with the upper member and lower member engaging in a telescopic manner and establishing a cavity between the two members when assembled. Spacers may be inserted in the cavity to lengthen the vertebral body replacement element. The present invention further concerns a system and method for expanding and distracting a vertebral body replacement element into and within the spinal column of a patient.

What is claimed: 
     
         1 . An adjustable vertebral body replacement assembly arranged in an intervertebral space between adjacent vertebrae, comprising:
 a first component defining a body having a first end and an open second end;   a second component defining a body having a third end, and a fourth from which extends a protrusion, said protrusion slidably engaged within said open second end; and   a removable spacer arranged between said second end and said fourth end.   
     
     
         2 . The adjustable vertebral body replacement assembly as claimed in  claim 2 , wherein said spacer at least partially encircles said protrusion of said second component. 
     
     
         3 . The adjustable vertebral body replacement assembly as claimed in  claim 2 , wherein the spacer further comprises a central opening having an inner surface that contacts an outer surface of said protrusion. 
     
     
         4 . The adjustable vertebral body replacement assembly as claimed in  claim 3 , further comprising an outer surface of the body of the second component and a lip formed on the third end of the second component between the protrusion and the outer surface. 
     
     
         5 . The adjustable vertebral body replacement assembly as claimed in  claim 4 , wherein the spacer contacts the lip to establish a vertebral body length of the vertebral body replacement. 
     
     
         6 . The adjustable vertebral body replacement assembly as claimed in  claim 1 , wherein the first end and fourth end are substantially flat and contact adjacent vertebrae. 
     
     
         7 . The adjustable vertebral body replacement assembly as claimed in  claim 1 , wherein the first component and the second component further comprise a plurality of openings or channels. 
     
     
         8 . The adjustable vertebral body replacement assembly as claimed in  claim 1 , wherein the first end and the fourth end include a series of teeth or serrations to secure the first and second components to adjacent vertebrae. 
     
     
         9 . The adjustable vertebral body replacement assembly as claimed in  claim 1 , wherein the cavity comprises a keyway and the protrusion comprises a key sized to fit within the keyway to resist relative rotation between the first component and the second component. 
     
     
         10 . The adjustable vertebral body replacement assembly as claimed in  claim 1 , wherein the first component and the second component each have a distraction slot for receiving a first end and a second end of a distracter instrument. 
     
     
         11 . The adjustable vertebral body replacement assembly as claimed in  claim 1 , wherein a cross section of the first component and a cross section of the second component are substantially circular. 
     
     
         12 . The adjustable vertebral body replacement member as claimed in  claim 1 , wherein a cross section of the first component and a cross section of the second component are substantially rectangular or square. 
     
     
         13 . The adjustable vertebral body replacement member as claimed in  claim 1 , wherein the vertebral body replacement member is adjustable by sliding the first component telescopically with respect to the second component. 
     
     
         14 . The adjustable vertebral body replacement member as claimed in  claim 3 , wherein the protrusion is sized to create a sliding joint with no relative rotation between the first component and the second component. 
     
     
         15 . A kit for replacing a damaged vertebral disc in a spinal column, comprising:
 a vertebral body replacement assembly, comprising
 a first component defining a first body having a first top and an open first bottom, 
 a second component defining a second body having a second bottom, a second top, and 
 a protrusion that extends from the second top and is slidably engaged within the open first bottom; 
   a spacer arranged between the open first bottom and the second top and slides onto an outer surface of said protrusion; and   a distracter tool having a first arm and a second arm, the first arm insertable into a recess on the first component body and the second arm insertable into a recess on the second component body for installing, adjusting, and removing the vertebral body replacement member.   
     
     
         16 . The kit as claimed in  claim 15 , wherein the first top and the second bottom include a series of teeth or serrations that contact adjacent vertebrae between which the vertebral body replacement is installed. 
     
     
         17 . The kit as claimed in  claim 15 , wherein a surface of the cavity comprises a keyway and a surface of the protrusion comprises a key sized to fit within the keyway to prevent relative rotation between the first component and the second component. 
     
     
         18 . The kit as claimed in  claim 15 , wherein a cross section of the first component and a cross section of the second component are substantially circular. 
     
     
         19 . The kit as claimed in  claim 15 , wherein said spacer is a split ring spacer having a portion of said spacer ring removed to facilitate installation and removal of said ring shaped spacer. 
     
     
         20 . The kit as claimed in  claim 15 , spacer is a non-compressible spacer.