Anatomic spinal implant having anatomic bearing surfaces

An implant for insertion between a first vertebra and a second vertebra, the first vertebra having a generally vertically extending first peripheral wall and a first cortical bone endplate and the second vertebra having a generally vertically extending second peripheral wall and a second cortical bone endplate, wherein the implant comprises:

• a first terminal part defining a trailing face, a first bearing surface adapted to bear against a portion of the first cortical bone endplate proximate to the first peripheral wall, and an opposite second bearing surface adapted to bear against a portion of the second cortical bone endplate proximate to the second peripheral wall;
• a second terminal part opposite said first terminal part, said second terminal part including an anti-expulsion feature and having an insertion face extending from a third bearing surface to a fourth bearing surface, said implant having a longitudinal axis extending through said trailing face of said first terminal part and said insertion face of said second terminal part, and having a cross section in a first plane extending through said first bearing surface and said second bearing surface, and along the longitudinal axis, the first plane bisecting said first bearing surface in two halves;
• a first side and an opposite second side, said first side and said second side extending from said first terminal part to said second terminal part, portions of said first side and said second side being substantially flat, said substantially flat portions intersecting a second plane that is perpendicular to the first plane and extends through said insertion face and said trailing face, wherein said substantially flat portions of said first side and said second side are symmetrical about the first plane;
• and
• upper and lower bearing surfaces proximate each of said first and second sides, said upper and lower bearing surfaces proximate said first and second sides being intersected by a third plane that is perpendicular to the first and second planes, a maximum first distance between said upper and lower bearing services proximate said first side measured perpendicular to the second plane and in the third plane being greater than a maximum second distance between said first and second bearing surfaces measured in a direction parallel to the maximum first distance and a maximum third distance between said third and fourth bearing surfaces measured in a direction parallel to the maximum first distance.

An implant for insertion between a first vertebra and a second vertebra, the first vertebra having a generally vertically extending first peripheral wall and a first cortical bone endplate and the second vertebra having a generally vertically extending second peripheral wall and a second cortical bone endplate, wherein the implant comprises:

• a first terminal part defining a trailing face, a first bearing surface adapted to bear against a portion of the first cortical bone endplate proximate to the first peripheral wall, and an opposite second bearing surface adapted to bear against a portion of the second cortical bone endplate proximate to the second peripheral wall;
• a second terminal part opposite said first terminal part, said second terminal part including an anti-expulsion feature and having an insertion face extending from a third bearing surface to a fourth bearing surface, said implant having a longitudinal axis extending through said trailing face of said first terminal part and said insertion face of said second terminal part, and having a cross section in a first plane extending through said first bearing surface and said second bearing surface, and along the longitudinal axis, the first plane bisecting said first bearing surface in two halves;
• a first side and an opposite second side, said first side and said second side extending from said first terminal part to said second terminal part, said first and second sides intersecting a second plane that is perpendicular to the first plane and extends through said insertion face and said trailing face, wherein a cross section of said implant at the second plane is generally rectangular;
• and
• upper and lower bearing surfaces proximate each of said first and second sides, wherein said upper and lower bearing surfaces proximate said first and second sides are, at least in part, convex relative to the second plane.