Patent ID: 7094237

Claim:
Device for treatment of the spine, comprising: anchor members ( 1 , 2 ) adapted to be anchored in vertebrae, each having a cylindrical screwthreaded portion ( 5 ) onto which is screwed a clamping nut ( 8 ), and an anchor portion connected to the cylindrical screwthreaded portion ( 5 ) by an intermediate stop flange ( 7 ), at least one circular section securing rod ( 3 ) having a smooth exterior surface, sliding connecting members ( 4 ) for connecting the anchor members ( 1 , 2 ) to the securing rod ( 3 ), the sliding connecting members ( 4 ) including a first hole ( 16 ) conformed to have the cylindrical screwthreaded portion ( 5 ) of an anchor member passed through it to fasten it to an anchor member, the sliding connecting members having a top transverse groove ( 17 ) conformed to receive a section of the securing rod ( 3 ), with clamping means for selectively clamping and unclamping the securing rod ( 3 ) in said transverse groove ( 17 ), wherein the clamping means comprise: a clamping screw ( 21 ), having a screwthreaded shank and a head, a clamping hole ( 20 ) in the bottom of the transverse groove of the sliding member, separate from the first hole ( 16 ) and offset laterally relative to the first hole ( 16 ), a cylindrical bearing surface ( 18 ) constituting a first edge of the transverse groove ( 17 ) and conformed to receive a section of the securing rod ( 3 ), an oblique bearing surface ( 19 ) constituting an opposite edge of the transverse groove ( 17 ) and inclined relative to the axis of the clamping hole, a clamping member ( 22 ) in the corner of the transverse groove ( 17 ) between the oblique bearing surface ( 19 ) and the securing rod ( 3 ) and adapted to be pushed toward the bottom of the transverse groove ( 17 ) by the clamping screw ( 21 ) in a first direction, the clamping member having a bearing face ( 22 b ) bearing and sliding on the oblique bearing surface ( 19 ) in a second direction, and having an opposite thrust face ( 22 c ) bearing on the securing rod ( 3 ) in a third direction, to immobilize it in the transverse groove ( 17 ), wherein both the second and third directions are non-parallel to said first direction.