any so called surgical material presenting the necessary hardness for example of stainless steel according to the example shown in fig4 the inclined flat or face 2 permits as a first step to provide some play which makes it possible to insert the screwdriver 1 into the pentagonal recess or at five socket faces e of the head of the screw v as the screwdriver 1 is inserted into the recess e of the screw head the play diminishes and disappears altogether thus permitting the screwdriver to perfectly match up with the shape of the recess e of the screw v fig5 furthermore when the screwdriver is completely inserted into the recess e of the head of screw v the inclined face 2 makes it possible to place the two faces or flats 3 and 4 opposite the inclined flat 2 closely against the corresponding socket faces of the recess of the screw as indicated by the arrow on fig5 and 6 the screwdriver 1 then finds itself immobilized in the head of the screw v and the inclined flat creates a gripping effect thus the stress applied to the screwdriver 1 to screw or unscrew an orthopedic screw is transferred to said screw through the intermediary of the edge 2 a of the inclined flat 2 by the faces 3 and 4 opposite to said inclined flat 2 and by the angle comprised between said faces 3 and 4 the pentagon of the screwdriver 1 being convex and regular its interior angles amount to 108.