An implantable spinous process fixation device includes a k-shaped component comprising an elongated plate and top and bottom deformable plates extending at first and second angles from a first surface of the elongated plate, respectively, thereby defining first and second spaces between the elongated plate and the top and bottom deformable plates and a compression element configured to compress and move the first and second deformable plates toward the elongated plate and to change the first and the second angles, respectively. The first and second spaces are configured to receive first and second spinous processes, respectively. Compressing and moving the first and second deformable plates toward the elongated plate results in engaging the first surface of the elongated plate and first surfaces of the top and bottom deformable plates with lateral surfaces of the first and second spinous processes, respectively.