| 摘要 |
The invention is related to a fastener and a bone fixation assembly for the internal fixation of vertebral bodies. The bone fastener includes a shank having a longitudinal axis, a head positioned adjacent the top end of the shank and having at least two portions separable in the axial direction. The head includes a bottom portion connected to the shank and a top portion connectable to the bottom portion. The bottom portion defines a socket situated coaxially to the longitudinal axis to accept a driver to rotate the fastener, and the top portion has an exterior with a convex design. |
