Intervertebral cage for spinal implant

An intervertebral cage for spinal implants, the intervertebral cage comprising:

• a front side;
• a right lateral side;
• a left lateral side;
• a rear side;
• a top side;
• and
• a bottom side,
• wherein the intervertebral cage is substantially cuboid with trapezoidal cross-section, the front side being thicker than the rear side, the right lateral side being thicker than the left lateral side, a thickness of the intervertebral cage decreasing along an anterior-posterior axis with a vertical dimension of the front side being a largest and a vertical dimension of the rear side being a smallest,
• wherein cross-sections of the intervertebral cage perpendicular to the anterior-posterior axis comprise a slanting portion and a flat portion of a predetermined length in the to side and the bottom side,
• wherein at least one of the top side and the bottom side has a slippage preventing structure formed thereon,
• wherein the slippage preventing structure includes a hooked structure, and
• wherein the hooked structure comprises a fixing portion and a movable hook, the movable hook being configured to self-rotate in accordance with an orientation of insertion of the intervertebral cage between vertebrae.