A manually guided implement having a housing that accommodates an internal combustion engine for driving a tool. Each dipole element comprises a triangular patch and a V-shaped tentacle patch extending from the triangular patch. The road-name extracting means extracts the road and its road name which are to be displayed from the road data to display the road image in the display area determined by the display area determining means. Fusion cages adapted for insertion into an unreamed disc space are provided to enhance load distribution between adjacent vertebral bodies and lateral stability of the spinal column.