US Patent 6918916 Target apparatus

The target apparatus for positioning a drilling tool with respect to a drilling channel to be created in a bone consists of a target hook and a guide arm which is releasably connected to this and on which there is arranged a receiver for the drilling tool, and a guide path in the form of a laterally through-going open groove for the guide arm. The guide arm may be displaced and fixed in the guide path. A simple assembly and disassembly of the apparatus is achieved in that the guide arm on the side of the apparatus is applied into the guide path through the groove opening and reversely, by lifting away out of the groove, may be separated from the target hook.