This creation provide one kind can stepless regulation expansion height expansion pedicle screw comprising: follow closely outside a hollow form, an interior nail, a polyaxial rotation thread head, a block and a set screw. The ball portion that the male end of the interior nail derives from nail outside the hollow form penetrates and matches with the end internal screw thread of nail outside the hollow form, the tooling hole of the interior nail is combined by instrument and is rotated, make the expansion leaves Jing of nail outside the hollow form to propping up outward, the propping up of expansion leaves can highly rotate interior follow closely by instrument and make stepless regulation. One fixed link must be across the screw thread in U-shaped body that the U-shaped body of polyaxial rotation thread head, a set screw must be screwed into the polyaxial rotation thread head and the fixed link is fixed in abutting, and gearing fixed link pushes against follow closely and fixed angle outside block and hollow form downwards.本創作提供一種可無段式調控膨脹高度之膨脹椎弓根螺釘，其包括：一中空狀外釘、一內釘、一多軸向轉動螺紋頭、一擋塊與一止付螺絲。該內釘之外螺紋端得自該中空狀外釘之圓球部穿入並與該中空狀外釘之末端處內螺紋相配合，藉由器械結合該內釘之工具孔並旋轉，使該中空狀外釘之膨脹葉片逕向向外撐起，膨脹葉片之撐起高度可藉由器械旋轉該內釘作無段式調控。一固定桿得穿過多軸向轉動螺紋頭之U形體，一止付螺絲得螺入該多軸向轉動螺紋頭之U形體內之螺紋並抵緊固定該固定桿，連動固定桿向下抵緊擋塊及中空狀外釘而固定角度。
