Osteosynthesis screw, especially for application by a translaminar vertebral screw

摘要

An osteosynthesis screw (1) used especially for application by a translaminar vertebral screw, comprises a shaft (3) at least partially provided with a thread (2) and a head (4) formed at one of its ends and having a notch (5) for a tool. Said shaft (3) has a section (A) with a thread (2) on the end section oriented towards the head (4). The remaining section (B) of the shaft (3) up to the free end is produced without a thread. The head (4) has a diameter (D1) corresponding at least approximately to the outer diameter (DA) of the thread (2) and is provided with the inner notch (5) for a tool. The section (A) of the shaft (3) with the thread (2) has a configuration of uniform thickness, e.g. a trilobular configuration. Thus, the invention provides an osteosynthesis screw (1) exhibiting a short section (A) with a thread (2) and a long section (B) without a thread, said screw having a pull-out head (4) which is secured both axially and rotationally.