The bone screw, the screw thread the shaft which (2) is attached (3), the front end (4) and the rear end it is something which (5) is included, the aforementioned shaft (3) the central limits (L4) major diameter the d or aforementioned screw thread (2) root diameter k, faces to the aforementioned front end (4) following, it keeps decreasing to size d1 of size d2 of large texture and the k2 empty small awakening and k1, d1 or k1 are not zero here. The aforementioned shaft (3) was arranged in the same axis, the open-ended sleeve (10) it has for radial, the sleeve the aforementioned shaft (3) small awakening major diameter has been located to the part which possesses d1 or k1.< Selective figure > Figure 1骨ねじは、ねじ山(2)を付けたシャフト(3)、前端(4)および後端(5)を含むものであり、前記シャフト(3)の中央域(L4)の外径「d」または前記ねじ山(2)の谷径「k」が、前記前端(4)に向かうに従って、大きめの寸法「d2」および「k2」から小さめの寸法「d1」および「k1」に減少して行き、ここで「d1」および「k1」はゼロではない。前記シャフト(3)は同軸に配置された、半径方向に拡張可能なスリーブ(10)を備えてあり、スリーブは前記シャフト(3)の小さめ外径「d1」または「k1」を有する部分に位置している。【選択図】 図1
