A dynamic bone anchor is provided comprising a longitudinal core member (2, 2, 2", 2) having a first end (21) and a second end (22) and a longitudinal axis (L) extending through the first end and the second end at least one tubular segment (3, 3, 3") provided on the core member, the tubular segment having an outer bone engagement structure (31) wherein in a first configuration the at least one tubular segment is movable on the core member along the longitudinal axis and wherein in an optional second configuration, the at least one tubular segment is fixed relative to the core member. Two or more tubular segments may be provided.本案提供一種動態骨骼固定器,包括:縱長芯部構件(2,2,2",2),具有第一端(21)和第二端(22),以及延伸貫穿第一端和第二端之縱軸線(L);至少一管狀段(3,3,3"),設在芯部構件上,管狀段具有外部骨骼結合結構(31);其中在第一組態時,至少一管狀段可在芯部構件上沿縱軸線運動;又其中在視情況之第二組態時,至少一管狀段係相對於芯部構件固定不動。可設二或以上之管狀段。1‧‧‧動態骨骼固定器2‧‧‧芯部構件3,3,3"‧‧‧管狀段4‧‧‧尖端構件5‧‧‧頭部21‧‧‧芯部構件第一端22‧‧‧芯部構件第二端25,26‧‧‧連接部27‧‧‧圓筒部31‧‧‧骨骼螺紋33‧‧‧圓筒部34‧‧‧管狀段內側L‧‧‧芯部構件縱軸線
