Abstract: An adapter unit for a mechanical tissue cutting implement such as a shaver, morcellator or the like includes a mounting block from which an electrically insulating sheath extends. The sheath fits over the cannula or shaft of the cutting implement, and is secured in alignment and attached so that the cutting tip, for example, the tool and its window in the cannula tip, are exposed through the sheath. A conductor, which may be a conductive layer, extends along the length of the sheath and is exposed to form a distal electrode at the tip in close proximity to the opening, constituting one electrode of a bipolar electrode arrangement at the exposed tool. The other electrode is provided by electrical connection to the implement itself, so that a high current density path is formed through tissue in the cutting region.

Abstract: An electrosurgical instrument has a handle and a body which position and close a jaw about a tissue site for simultaneously cutting and sealing relatively large tissue structures. The jaw includes an electrosurgical cutting member, which may be a blade or wire, against which tissue is biased along a cut line, and a clamping assembly that clamps a region adjacent to or surrounding the cut line. The clamping assembly includes sealing electrodes for heating the region and welding tissue along the side of the cut as the cutter parts the tissue. The clamping assembly preferably has first and second clamping jaws extending in parallel to grip the tissue as tension is released by the cut, allowing dependable and complete sealing of the cut ends over an extended time while the tissue is immobilized.