05697913 is referenced by 75 patents and cites 15 patents.

A trocar including a cannula with a tubular sleeve having a stepped region thereon is disclosed. The stepped region has a plurality of discrete steps. Each step has a step floor and a step support base tapering radially inwardly from the step floor to an adjacent step floor. When the trocar is inserted through the body wall, and the stepped region of the sleeve of the cannula contacts the body wall, the force required to inadvertently pull the cannula out of the body wall when surgical instruments are withdrawn from the cannula increases. Thus, the tubular sleeve of the cannula increases the retention force of the cannula during surgery. The retention force is increased without appreciably affecting the force required to insert the trocar through the body wall. Additionally, these benefits are achieved without using helical threads or externally mounted stability devices, which add cost, complexity and increased risk of causing unwanted tissue trauma.

Title
Trocar including cannula with stepped region
Application Number
8/694980
Publication Number
5697913
Application Date
August 9, 1996
Publication Date
December 16, 1997
Inventor
Richard C Smith
Loveland
OH, US
Charles S Black
Cincinnati
OH, US
Jorge N Gutierrez
Cincinnati
OH, US
Thomas J Sierocuk
West Chester
OH, US
Agent
Matthew S Goodwin
Assignee
Ethicon Endo Surgery
OH, US
IPC
A61M 5/178
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