Patent ID: 6471705
Filing Date: 2002-10-29
Classification: A61B

Abstract:
A bone screw comprising:a screw part having a head and a threaded portion; a head-side cylindrical reception part for receiving a rod to be connected with the screw part; said reception part comprising an open bore hole and a U-shaped cross section having two free legs provided with an exterior thread; and an exterior nut which can be screwed onto the exterior thread, wherein the exterior nut comprises an inside sleeve-shaped element having a predetermined inner dimension and an outer diameter which is almost equal to or slightly less than the diameter of the bore, and a pressure element arranged therein, said pressure element comprising an end facing the bottom of said bore and a first section at said end, the outer dimension of said first section being greater than said predetermined inner dimension and said first section causing said sleeve-shaped element to be expanded when pressure is exerted on the rod to be received.