Abstract: A surgical screw has a head being, at least in a portion, hemispherical. A smooth continuous join exists between the head and a shank of the screw, the head being of the same, or larger, diameter as the shank. To drive the screw a drive socket is provided concentrically within the head, and a cannulation is provided concentrically of the shank and it opens into the socket so as to allow the screw to be threaded along a guide wire or similar. The shank has a smooth or soft thread so as to provide an interlocking fixation of a bone end of a tendon graft within a prepared hole of a bone, but without damaging either bone structures. The hemispherical portion provides a smooth continuous curved surface over which a graft may flex and move without fatigue or suffering stress concentrations.