| 摘要 |
An instrument used in spinal surgery - a so called spinal joint - comprises two blocks (1,11) which are pivotally connected to each other. One of said blocks (1) is provided with a bone screw by means of which it can be secured to a vertebra while the other one (11) has a guide (13) for a screw spindle for connecting the spinal joint with another spinal joint. In order to securely lock the two blocks relative to each other in various angular positions the pivotal connection between the blocks consists of a stud (19) which projects from one of the blocks (11) and which with a play fits in a hole (8) in the other block (1) and said stud is provided with serrations (19) which may be brought into engagement with corresponding serrations (9) in the hole (8) of said other block by means of a locking screw (36) acting upon said stud to displace it transversely. On each side of the serrations (9) of said hole there are recessed portions (10a,10b) to receive those serrations of stud (18) which are not in engagement with serrations of the hole (8). <IMAGE> |
