A conical interspinous apparatus comprising: an insertion portion with a proximal end, a distal end, and conical screw-shaped grooves configured to distract two adjacent spinous processes; a shaft portion, coupled to the distal end of the insertion portion, and having a smaller cross-section than a cross-section at the distal end of the insertion portion, such that the two spinous processes rest on the shaft portion; and a clamp portion being movable and securable along the shaft, and being configured to secure the two spinous processes between the clamp portion and the distal end of the insertion portion.