Patent ID: 8622969

Claim:
A trocar comprising: a retention cannula comprising: a proximal end, a distal end, and a longitudinal axis; a cannula body between the proximal end of the cannula and the distal end, the cannula body having an outer diameter, and the cannula body comprising a cannula wall defining a lumen extending between the proximal end and the distal end; and an inverted, tissue retention pattern extending into the cannula wall, the tissue retention pattern comprising a continuous inverted pattern defined by a plurality of flat cuts extending generally perpendicular to the longitudinal axis of the retention cannula, and a plurality of diagonal cuts extending generally transverse to the longitudinal axis of the retention cannula and positioned such that each of the plurality of flat cuts is connected to an adjacent one of the plurality of flat cuts by a diagonal cut; and wherein an outer diameter of the inverted pattern is not greater than the outer diameter of the cannula body.