05295994 is referenced by 338 patents and cites 26 patents.

An active cannula or sleeve which does more than merely maintain a channel or passage is usable to enlarge a channel or passage, to position a scope or instrument, to move or locate tissue, etc. The cannula can vary in size or shape as needed, intraoperatively. Because a cannula of the present invention is expandable, the surgeon can make a small relatively small incision, stretch the tissue with the expandable cannula, contract the cannula and remove it, allowing the skin to come back to its unstretched condition. Thus, a smaller incision can be made to fit the same size instrument. This results in less trauma and scarring and an easier operation. The cannulas are or can assume such a non-circular shape, to fit into a natural skin opening and cause less trauma. The devices can be used to seal off a space; to expand an existing space or a potential space for working or visualization; to move tissue (for example, to stretch an incision) or to protect it.

Title
Active cannulas
Application Number
7/792730
Publication Number
5295994
Application Date
November 15, 1991
Publication Date
March 22, 1994
Inventor
Peter M Bonutti
1303 W. Evergreen Plz., Effingham, 62401
IL, US
Agent
Tarolli Sundheim & Covell
IPC
A61B 17/00
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