Locking trocar sleeve

An improved method for inserting a trocar assembly through the abdominal wall into the abdominal cavity, comprising the steps of:

• inserting a trocar through a passage in a trocar sleeve so that a cutting end of the trocar extends from a first end of the trocar sleeve;
• forming an incision through the abdominal wall with the trocar and inserting the first end of the trocar sleeve into the abdominal cavity;
• and
• expanding a portion of the first end within the abdominal cavity so that the expanded portion is of a dimension substantially greater than the dimension of the incision to abut the inner surface of the abdominal wall about the incision to resist withdrawal of the trocar sleeve from the abdominal cavity;
• and
• removing the trocar and thereby automatically retracting the portion of the first end.

A method for inserting a laparoscopic instrument into a trocar assembly and into the abdominal cavity, comprising the steps of:

• (a) introducing into the abdominal cavity a laparoscopic trocar assembly, said assembly comprising:
• a trocar sleeve having a through passage, and a first end extending into the abdominal cavity through a laparoscopic incision in the abdominal wall, the first end having a first external dimension for passage through the incision;
• and
• means for expanding a portion of the first end within the abdominal cavity so that the external dimension of the first end within the cavity is expanded to a larger, second external dimension, the first end abutting the inner abdominal wall about the incision when expanded to the second external dimension to resist withdrawal of the trocar sleeve from the abdominal cavity;
• (b) expanding a portion of the first end within the abdominal cavity to place the external dimension of the first end within the cavity to an expanded larger, second external dimension;
• (c) introducing through said expanded portion a laparoscopic instrument into said assembly and through said abdominal cavity;
• and
• (d) withdrawing the laparoscopic instrument from within the abdominal wall out of said assembly, and retracting said portion of the first end within the abdominal cavity so that the external dimension of the first end is retracted to the first external dimension prior to withdrawal of the assembly from the abdominal cavity.