A medical screw which can be withdrawn easily from a fracture site in which the medical screw is screwed in is provided. A reverse external thread portion 11h formed in a reverse direction to a direction of a thread of a screw thread portion 11b of a distal end portion 11a is provided on an outer periphery of a head portion 11e of a medical screw 11, and a reverse internal thread portion 14a provided at a front end portion of a rod-shaped member of a withdrawal operating jig 14 is engaged with the reverse external thread portion 11h by rotating in a reverse direction to a direction of a thread of the screw thread portion 11b, whereby the screw 11 and the withdrawal operating jig 14 are unified. Furthermore, the withdrawal operating jig 14 is rotated in a reverse direction to the direction of screwing in of the screw 11, so that the screw 11 is pulled out of the body by being loosened and withdrawn from a fracture site D.【課題】捩じ込んだ骨折部位から容易に抜去できる医療用スクリューを得る。【解決手段】医療用スクリュー11の頭部11eの外周に、先端部11aのスクリューねじ部11bと逆ねじ方向に刻設した逆外ねじ部11hを設け、この逆外ねじ部11hに抜去操作治具14の棒状体の前端部に設けた逆内ねじ部14aをスクリューねじ部11bのねじ方向と逆方向に回転して螺合させることにより、スクリュー11と抜去操作治具14とを一体化する。更に、抜去操作治具14をスクリュー11の捩じ込み方向と逆方向に回転させることで、スクリュー11を骨折部位Dから緩めて抜去し、体外に引き出す。【選択図】 図11
