| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a polyaxial bone anchoring device that provides safe anchoring, and simultaneously, has an enlarged pivoting angle. <P>SOLUTION: The polyaxial bone anchoring device includes: a bone anchoring element (1); a receiving part (4); and an insert piece (6). The insert piece (6) has a boundary edge having a seat for a head (3) of the bone anchoring element (1) and an opening (17). The opening (17) is smaller than the head (3) so as to prevent the head (3) from passing therethrough. The boundary edge is configured to allow the bone anchoring element (1) to pivot with respect to the central axis (C) at a first location of the boundary edge at a larger angle than the angle at another location of the boundary edge. The insert piece (6) is rotatable with respect to the receiving part (4). The receiving part (4) has a first flat surface portion that is for supporting the insert piece (6) and substantially vertical to the central axis (C). The insert piece (6) has a corresponding second flat surface portion facing the first flat surface portion. <P>COPYRIGHT: (C)2013,JPO&INPIT |
