| 摘要 |
<p>The invention relates to a ceramic hip joint prosthesis head (5) for use with a trunnion (2), the trunnion (2) having a frustoconical end (4) comprising a first section having a diameter of about 12 mm which expands inward at a total angle of about 6 degrees to form a second section having a diameter of about 14 mm, wherein each head (5) comprises: a) a substantially spherical outer diamter of about 22.22 mm, b) a centerpoint (90), and c) a recess (92) which forms a taper wall (6) extending inward from the outer diameter of the head (5), wherein the taper wall (6) has a shape suitable for taper fitting upon the frustoconical end (4) of the trunnion (2) to produce contact between the taper wall (6) and the first section of the frustoconical end (4) of the trunnion (2), a perimeter being defined by the deepest contact (89) between the taper wall (6) and the first section of the frustoconical end (4) of the trunion (2), the perimeter having a centerpoint, and wherein each head (5) when taper fit upon the frustoconical end (4) of the trunnion (2), has a rupture load of at least 46 kN and is characterized by a distance (D) between a) the centerpoint (90) of the head (5) and b) the centerpoint of the perimeter defined by the deepest contact (89) between the taper wall (6) and the first section of the frustoconical end (4) of the trunnion (2) wherein (D) has an absolute value of less than 3 mm.</p> |
