Provided is a dynamic bone anchor comprisingan anchor member (1, 1′, 1″) having a tubular body defining an anchor axis (C), the anchor member comprising a plurality of barb elements (13),wherein each barb element (13) is moveable between a first position adjacent to a surface of the tubular body and a second position farther from the surface of the tubular body than the first position andwherein at least a portion of a free cutting edge (13c) of the barb elements is inclined at an angle corresponding to a helical angle that extends for at least one full turn around the anchor axis (C), andwherein the anchor member is made at least partially of a first material that comprises a Ni—Ti based shape memory alloy； anda longitudinal core member being at least partially provided in the tubular body and having a first portion (23, 23′, 23″； 3, 3″) that is not connected to the anchor member such that the anchor member is movable relative thereto and a second portion (25, 22a) that is connected to the anchor member.
