| 摘要 |
<p>A bone anchoring device is provided, comprising
an anchoring element comprising a shank (14) to be anchored in a bone or a vertebra and a head (15), the head having an exterior surface with a spherical segment-shaped portion (16), wherein said shank (14) and said head (15) are separate parts;
a receiving portion (1) comprising a first end (2), a second end (3) opposite to the first end, a longitudinal axis (4) passing through the two ends, a bore (5) coaxial with the longitudinal axis, a first region (7) adjacent to the second end (3) for receiving a spherical segment-shaped section (16) of said head; and
an element (17; 20; 21) which exerts pressure on said head (15) to lock said head in the receiving portion;
wherein said head has hollow inner portion (25) to receive a free end portion (22) of said shank and wherein said head and said end portion are formed such that the end portion is elastically clamped by said head while said head is not locked.</p> |
