Modular signal interface system and powered trocar

A modular signal interface system for providing electrical communication with a surgical instrument when the surgical instrument is inserted into a cannula of a trocar, the system comprising:

• (a) a signal interface adapter provided on, or adapted to be mounted on the trocar, the signal interface adapter having a central aperture extending therethrough and a proximal face having a plurality of conductive contacts;
• and
• (b) an instrument connector provided on, or adapted to be mounted on a shaft of the surgical instrument, the instrument connector having a central aperture extending therethrough and a distal face having a plurality of conductive contacts, the instrument connector adapted for providing electrical communication between one or more of said contacts of the instrument connector and the surgical instrument on which the instrument connector is provided or mounted;
• wherein the signal interface adapter and the instrument connector are adapted for mating engagement such that, when matingly engaged, said central apertures are axially aligned and predetermined ones of the plurality of contacts of the signal interface adapter are in conductive contact with predetermined ones of the plurality of contacts of the instrument connector.