US Patent 7905897 Trocar device

A surgical device is described. The surgical device may comprise a rotatable cutter configured to cut tissue for insertion of a cannula, and a first driver configured to be driven by a motor arrangement and to rotate the cutter. The surgical device may further include, for example, the cannula, at least one of the rotatable cutter and the first driver being disposed in a bore of the cannula. In one embodiment, the rotatable cutter may include an auger having a cutting thread. In another embodiment, the rotatable cutter may include a disk-shaped blade.