A posterior spinal osteosynthesis device for providing a transverse connection between two vertebral rods extending along a spinal segment wherein the device includes pairs of hooks adapted to laterally engage the vertebra with each pair being connected by a pair of parallel rods which are elastically bent to form a transverse arc whose ends are engaged in bores within the hooks. The device comprises a wearable stimulator head and a wearable stimulator controller. The second intake cam is phase adjustable relative to the crankshaft independently of the phase of the first intake cam relative to the crankshaft. The result of the comparison can be used to determine whether a virus scan is currently required for a resource, on the basis that a resource which is unchanged since it was classified virus-free remains virus-free and a resource which is identical to a virus-scanned resource does not require duplication of the virus scan. The chain attachment fitting is arranged in the straightening of a chassis frame, which is bent in the vertical direction or is crooked, to secure a chain that is attached to the chassis frame.