Patent ID: 8888692

Claim:
A cannula assembly comprising: a cannula having a proximal end, a distal end opposite the proximal end, and a lumen extending from the proximal end to the distal end along a longitudinal axis, the lumen configured to receive a surgical instrument therein, the cannula comprising: a generally tubular cannula body extending from adjacent the proximal end to the distal end of the cannula, the cannula body having an exterior surface and a first outer diameter; an annular groove formed in the exterior surface of the cannula body adjacent the distal end of the cannula, the annular groove transverse to the longitudinal axis, the annular groove having a second outer diameter smaller than the first outer diameter of the cannula body; and a sleeve having a proximal end and a distal end, the sleeve disposed around the cannula from adjacent the proximal end to the annular groove, the sleeve formed in a monolithic, unitary construction comprising: a coupler at the proximal end sized and configured to engage the cannula; an elongate tubular body extending distally from the coupler, the elongate tubular body having a first thickness; a balloon positioned distal the elongate tubular body, the balloon having a second thickness smaller than the first thickness; and an annular ring distal the balloon, the annular ring positioned in the annular groove of the cannula, the annular ring having a third thickness and a third inner diameter in an undisturbed state, the third thickness larger than the first thickness of the elongate tubular body, the third inner diameter of the annular ring in an undisturbed state smaller than the second outer diameter of the annular groove to define an interference fit between the sleeve and the cannula.