| 摘要 |
<p>An instrument for holding and inserting a bone anchor into the bone, in particular for use with a pedicle screw, is provided, wherein the bone anchor (100) comprises a shank (101) for anchoring in the bone and a head (102); the instrument comprising a holding member (2) for holding the head (102) of the bone anchor, the holding member (2) comprising at least two arms (25a, 25b) that are configured to at least partially encompass the head (102) of the bone anchor and wherein the at least two arms (25a, 25b) comprise an inner surface forming a seat (26) for the head; a drive shaft (1) for engaging the head (102) of the bone anchor, the drive shaft (1) defining a longitudinal axis (L) of the instrument; and a displacement member (3) that is configured to act onto the holding member (2) such that the holding member (2) can assume a first configuration in which it is configured to permit the head to enter the seat (26) and a second configuration in which it is configured to hold the head in the seat (26); characterized in that; the drive shaft (1) comprises an abutment surface (14a) for the head and that the seat (26) is provided at such an axial position of the holding member (2) relative to the drive shaft (1) that an inserted head (102) is pressed against the abutment surface (14a) in the second configuration.</p> |
