Patent ID: 6398785
Filing Date: 2002-06-04
Classification: A61B,A61F

Abstract:
Apparatus for retention of tissue grafts and bone plates to a bone site comprising an elongated bone screw body member having a generally cylindrical shaft having a longitudinal axis and a selected diameter and first and second opposite end portions, a sharply pointed, piercing and cutting tip formed at the first end portion aligned with the longitudinal axis, helical drill flutes formed on the shaft along a first axial length of the shaft having an outer diameter generally equal to the selected diameter, the helical drill flutes being separated from one another by generally line contact along the first axial length, self-tapping bone screw threads formed on the shaft along a second axial length of the shaft, the bone screw threads having an inner diameter generally equal to the selected diameter and being contiguous with the first axial length, the self-tapping bone screw threads having a second outer diameter greater than the selected diameter, the helical drill flutes aligned with and forming a continuation of the self-tapping bone screw threads along a first portion of the second axial length forming cutting flutes and a driving head formed at the second end portion of the shaft, the driving head extending radially outwardly beyond the shaft forming an outer most periphery and being formed with a frusto-conical surface extending from the outer most periphery to the shaft, the diameter of the frusto-conical surface increasing in a direction going from the first end portion to the second end portion, and a female driving spline formed at the second end portion of the member aligned with the longitudinal axis of the body member, the female driving spline comprises a polygonal central recess and a radially extending slot communicating with the central recess, and a circular bore extending along the longitudinal axis, the circular bore being in communication with, and extending beyond, the central recess.