Expandable Helical Cage

Abstract

An expandable implant having a helical body and first and second securing pieces. Ends of the helical body are connected to the first and second end pieces. The first and second end pieces can be rotated relative to one another to expand the implant from a first dimension to a selected second dimension. The implant further includes a locking arrangement to maintain the implant at the selected second dimension.

1 - 20 . (canceled)  
   
   
       21 . An expandable intervertebral implant, comprising: 
 a body member having a first condition defining a first height in a first direction, said body member rotatable to a second condition defining a second height in said first direction, said second height being greater than said first height; and    a locking member associated with said body member and configured to lock said body member in said second condition.    
   
   
       22 . The implant of claim  1 , wherein said body member includes a helically-shaped portion.  
   
   
       23 . The implant of claim  1 , wherein a length of the implant in a direction orthogonal to said first direction does not substantially change when said body member is rotated from said first condition to said second condition.  
   
   
       24 . The implant of claim  1 , wherein said locking member is configured to lock said body member in one of a plurality of positions intermediate said first condition and said second condition, wherein each of said plurality of positions corresponds to a height in said first direction that is intermediate said first height and said second height.  
   
   
       25 . A method of expanding an expandable intervertebral implant, the method comprising: 
 obtaining an implant having a body member and a locking member, the body member having a first condition defining a first height in a first direction and being rotatable to a second condition defining a second height in the first direction, the second height being greater than the first height;    inserting the implant at an implant site;    rotating the body member from the first condition to the second condition; and    locking the implant in the second condition with the locking member.