A bone anchoring device is provided comprising an anchoring element (1) a shank (2) to be anchored in a bone or a vertebra and a head (3), a receiving portion (5) comprising a first end (6) and a second end (7) opposite to the first end, a longitudinal axis (8) passing through the two ends, a bore (5) coaxial with the longitudinal axis, a first region (11) adjacent to the second end (7) for receiving said head and a recess (12) which is opened towards the first end (6) and which forms tWo free legs (15, 16) for receiving arod (14), a pressure element (20) which exerts a pressure on said head (3) to lock said head in the receiving portion (5), and a closure element (30;40, 45) cooperating with said legs (15, 16) to secure the rod in said recess (12), wherein said pressure element (17) has a first end (21) and a second end (22) opposite to the first end (21) and a recess (24) which is open towards the first end (21) to receive the rod, the depth of the recess (24) being larger than the diameter, of the rod and wherein in a pre-assembled state the bottom (27) of the recess (24) of the pressure element (17) projects over the bottom (13) of the recess (12) of the receiving ponion in a direction towards the first end (6) of the receiving portion (5).(Fig. 6)本案提供一種骨骼固定裝置,包括固定元件(1),有要固定於骨骼或脊椎的幹部(2),和頭部(3);以及接納部(5),包括第一端(6)和與第一端對立之第二端(7),通過二端之縱軸線(8),與縱軸線共軸之腔孔(9),鄰接第二端(7)之第一區(11),供接納該頭部,朝向第一端(6)開口之凹部(12)形成二自由股部(15,16),供接納桿(14),對該頭部(3)施壓之施壓元件(20),且把該頭部鎖定於接納部(5)內,和封閉元件(30;40,45)與該股部(15,16)合作,把桿穩固在該凹部(12)內,其中該施壓元件(17)具有第一端(21)和與第一端(21)對立之第二端(22),以及朝第一端(21)開口之凹部(24)以接納桿,凹部(24)的長度較桿的直徑大,且其中在預組裝狀態,施壓元件(17)的凹部(24)之底部(27),按朝向接納部(5)第一端(6)之方向,突出於接納部的凹部(12)之底部(13)上方。2...骨釘幹部5...接納部13...U形凹部之底部14...桿17...陰螺紋20...施壓元件24...U形凹部30...內螺釘32...第一圓筒形凸部33...第二圓筒形凸部40...螺帽43...末端開縫44...環形凸部45...固定螺釘
