Expansion type vertebra distraction device and assembly

The invention provides a deployable vertebra distraction device and assembly. The expanding type vertebra distraction device comprises a middle shaft body, a middle shaft body and a connecting piece, the middle shaft body is provided with a barrel-shaped structure and a distraction ring which are connected with each other, the side, away from the distraction ring, of the barrel-shaped structure is provided with an external thread, and the maximum outer diameter of the distraction ring is larger than the outer diameter of the barrel-shaped structure; the unfolding part sequentially comprises a lantern ring, a connecting part and a plurality of blades, the cylindrical structure is sleeved with the unfolding part, the connecting part is connected between the lantern ring and the blades, and the thicknesses of the blades are gradually increased from the tail ends away from the connecting part to the direction close to the connecting part; and when the opening ring moves towards the lantern ring, the blades are op