Intersomatic cage

Abstract

The invention relates to an intersomatic cage comprising a body ( 3 ) and a part ( 2 ) that is designed to dilate the intersomatic space between two vertebrae ( 8, 8 ′) by rotating the cage so that the cage ( 1 ) can be inserted into the space. The body ( 3 ) has a prism shape with a substantially planar upper surface ( 6 ) which can bear against the superior vertebral endplate ( 8 ) and a substantially planar lower surface ( 6 ′) which can bear against the inferior vertebral endplate ( 8 ′).

1 . An intersomatic cage system comprising:
 An intersomatic cage ( 1 ) which has an essentially flat superior surface ( 6 ) capable of resting against a superior vertebra ( 8 ), an essentially flat inferior surface ( 6 ′) capable of resting against an inferior vertebra and an anterior face ( 7 ) at one end of the intersomatic cage ( 1 ) between the superior and inferior surfaces ( 6 ,  6 ′); and   Two elongated members ( 13 ,  13 ′;  21 ,  21 ′) disposed in spaced-apart relationship that are fixed on the intersomatic cage ( 1 ) and protrude from the anterior face ( 7 ) and/or from the superior or inferior surface ( 6 ,  6 ′) of the intersomatic cage ( 1 ) or that at least a part of one of which is retractably mounted on the intersomatic cage ( 1 ) to be able to protrude from the anterior face ( 7 ) and/or from the superior or inferior surface ( 6 ,  6 ′) of the intersomatic cage ( 1 ), wherein said two protruding elongated members ( 13 ,  13 ′;  21 ,  21 ′) have outer parts that are spaced-apart by a distance greater than the distance between the superior and inferior surfaces ( 6 ,  6 ′) of the intersomatic cage ( 1 ) such that the two protruding spaced-apart elongated members ( 13 ,  13 ′;  21 ,  21 ′) are capable of expanding the intersomatic space between the two vertebrae ( 8 ,  8 ′) to introduce the intersomatic cage ( 1 ) in the intersomatic space when the two protruding spaced-apart elongated members ( 13 ,  13 ′;  21 ,  21 ′) are introduced between the two vertebrae ( 8 ,  8 ′).   
     
     
         2 . The intersomatic cage system according to  claim 1 , wherein the intersomatic cage ( 1 ) comprises at least one longitudinal groove ( 16 ) arranged along at least a portion of the essentially flat superior surface ( 6 ) or essentially flat inferior surface ( 6 ′) or along a lateral side of the intersomatic cage ( 1 ), which groove or grooves ( 16 ) lead into said anterior face ( 7 ) of the intersomatic cage ( 1 ), said at least one groove ( 16 ) being arranged to receive at least one said elongated member ( 13 ,  13 ′;  21 ,  21 ′) that protrudes into or is able to protrude into said anterior face ( 7 ). 
     
     
         3 . The intersomatic cage system according to  claim 2 , wherein said elongated member ( 13 ,  13 ′;  21 ,  21 ′) is retractably mounted in said at least one longitudinal groove ( 16 ) so it is able to protrude into said anterior face ( 7 ). 
     
     
         4 . The intersomatic cage system according to  claim 2 , wherein the intersomatic cage ( 1 ) comprises two grooves ( 16 ,  16 ′) which are intersected by a plane which is perpendicular to the anterior face ( 7 ) of the intersomatic cage ( 1 ). 
     
     
         5 . The intersomatic cage system according to  claim 4 , wherein said plane is perpendicular also to at least one of the essentially flat superior surface ( 6 ) or the essentially flat inferior surface ( 6 ′) of the intersomatic cage ( 1 ). 
     
     
         6 . The intersomatic cage system according to  claim 2 , wherein at least one groove ( 16 ) has a curved portion along its longitudinal length to receive an elongated member ( 13 ,  13 ′;  21 ,  21 ′) which is curved on at least one portion of its length. 
     
     
         7 . The intersomatic cage system according to  claim 1 , wherein said at least one elongated member ( 13 ,  13 ′;  21 ,  21 ′) has a trapezoidal, round, oval or oblong cross-section. 
     
     
         8 . The intersomatic cage system according to  claim 7 , wherein the cross section of the elongated member ( 13 ,  13 ′;  21 ,  21 ′) is not constant along its length. 
     
     
         9 . The intersomatic cage system according to  claim 1 , further comprising an ancillary placement element that is adapted to engage with end parts of the two elongated members ( 13 ,  13 ′;  21 ,  21 ′) that are opposite to front parts of the elongated members ( 13 ,  13 ′;  21 ,  21 ′) that engage with the intersomatic cage ( 1 ), said ancillary placement element being adapted for producing relative movements between the elongated members ( 13 ,  13 ′;  21 ,  21 ′) and the intersomatic cage ( 1 ). 
     
     
         10 . The intersomatic cage system according to  claim 9 , wherein the ancillary placement element comprises a connecting member ( 22 ) between said end parts of the two elongated members ( 13 ,  13 ′,  21 ,  21 ′) that are securable to a posterior part of a body ( 3 ) of the intersomatic cage ( 1 ). 
     
     
         11 . The intersomatic cage system according to  claim 10 , wherein the posterior part of the cage body ( 3 ) includes a screw pitch ( 223 ) for screwably receiving an instrument ( 222 ) for pushing the cage body ( 3 ). 
     
     
         12 . An intersomatic cage comprising a cage body ( 3 ) which has an essentially flat superior surface ( 6 ) capable of resting against a superior vertebra ( 8 ), an essentially flat inferior surface ( 6 ′) capable of resting against an inferior vertebra, two lateral sides ( 3 ′,  3 ″) and an anterior face ( 7 ) at one end of the cage body ( 3 ) between the superior and inferior surfaces ( 6 ,  6 ′), and defining a longitudinal direction leading into the anterior face ( 7 ) of the cage body ( 3 ), wherein the essentially flat superior and inferior surfaces ( 6 , 6 ′) of the cage body ( 3 ) are arranged relative to one another such that the height of the cage body ( 3 ) at the anterior face ( 7 ) or at one of the lateral sides ( 3 ″) is greater than the height of the cage body ( 3 ) at a posterior face or at the other one of the lateral sides ( 3 ′) and defines a part of the cage body ( 3 ) adjacent to the anterior face ( 7 ) or to the higher of the lateral sides ( 3 ″) where the essentially flat superior face ( 6 ) is most spaced apart from the essentially flat inferior face ( 6 ′), the cage body ( 3 ) comprising at least one longitudinal groove ( 16 ) arranged along at least a portion of the essentially flat superior surface ( 6 ) or the essentially flat inferior surface ( 6 ′) of the cage body ( 3 ) that encompasses said part of the cage body ( 3 ) adjacent to the anterior face ( 7 ) or to the higher of the lateral sides ( 3 ″) where the essentially flat superior surface ( 6 ) and the essentially flat inferior surface ( 6 ′) of the cage body ( 3 ) are most spaced apart. 
     
     
         13 . The intersomatic cage ( 1 ) according to  claim 12 , comprising two grooves ( 16 ,  16 ′) which are intersected by a plane which is perpendicular to the anterior face ( 7 ) of the cage body ( 3 ). 
     
     
         14 . The intersomatic cage ( 1 ) according to  claim 13 , wherein said plane is perpendicular also to at least one of the essentially flat superior surface ( 6 ) or the essentially flat inferior surface ( 6 ′) of the cage body ( 3 ). 
     
     
         15 . The intersomatic cage ( 1 ) according to  claim 14 , wherein the at least one groove ( 16 ) has a curved portion along its longitudinal length. 
     
     
         16 . The intersomatic cage ( 1 ) according to  claim 12 , wherein said at least one groove ( 16 ) has a trapezoidal, round, oval or oblong cross-section.