Surgical devices having a plurality of outwardly-biased flexible fins capable of both inward convergence and outward flexion, provide for fluid retention and soft tissue retraction during surgical procedures. The outwardly-biased flexible fins also provide for soft tissue compression, decreasing the length of the lumen or passageway through which instruments pass, allowing for a wider range of movement of instruments and better access to the surgical site, especially in patients with greater amounts of fat tissue that would otherwise require longer lumen lengths in prior art endoscopic cannulas. An obturator assembly including a cannulated handle member with a cannulated shaft attached to said handle member, said shaft extending distally and terminating at a cannulated obturator tip. A hood structure found on such obturator tip may be used to secure one or more flexible fins prior to deployment.
