A staged expansion vertebra retaining device comprises a main body (10) and a screw (20) inserted into the main body (10). The distal end of the screw (20) is provided with a push block (21). One end of the main body (10) has at least two movable support units (14). Each movable support unit (14) is split by a U-shaped groove (13) to form at least two movable support surfaces (141, 142) which are spaced and arranged in the form of inner and outer layers. The movable support surface (141) is first expanded by the push block (21), and then the other movable support surface (142) is continuously expanded at an appropriate angle. Thus, the applied force of the graft operation can be dispersed effectively. The present invention is adjustable for the height of the vertebra, which can be adapted for most people. The present invention is labor-saving, precise, and quick for a graft operation.本發明係提供一種階段式撐張之椎體固定件，其包含一本體及一穿入本體而末端設有迫推塊的螺桿；其特徵在於：該本體一端具有二個或二個以上的活動支撐張單元，各活動支撐張單元包含以U形剖溝剖設成二個或二個以上的活動支撐面，該各活動支撐面形成內、外層間隔排列，據使迫推塊可先撐張一活動支撐面外擴，在依序連續撐張其他活動支撐面外擴成適當角度支撐兩椎體間定位；藉此組成具階段式撐張結構，可有效分散植入施力，以避免滑脫重新調整不便，及具高度調整功能，以達手術植入更具省力、快速精準。
