| 摘要 |
The invention relates to a bone screw with a threaded part and a screw head, characterized in that a head plate (3) is provided between shank (5) and screw head (1) and on whose centre is located said screw head and that the transition zone (2) between the head plate and the screw head is constructed as a predetermined shearing zone, which shears at a torque corresponding to 0.2 to 0.4 times the pulling off force for separating head plate (3) and shank (5). |
