| 摘要 |
A multi-axial screw assembly comprises a receiver, a base member, a crown and a bone screw. The base member includes an aperture extending through the base member and an opening on a bottom portion of the base member. The base member is rotatable relative to the receiver and has an inner wall extending partially around the aperture. The crown is received in the receiver and configured to mate to the base member. The crown has a projection configured to extend into the opening of the base member. The projection is configured to have an abutting surface. The bone screw is located between the base member and the crown, the bone screw is configured to be provisionally fixed within the receiver by a force between the abutting surface of the projection and the inner wall of the base member.
|
