An obturator for use in penetrating tissue includes an elongate member defininga longitudinal axis, and having a proximal end and a distal end, and a penetratingmember adjacent the distal end of the elongate member. The penetrating memberhas a distal penetrating tip dimensioned to pass through tissue. The penetratingmember defines an external wall leading toward the penetrating tip. The externalwall includes a plurality of raised elements extending at least radially outwardlyrelative to the longitudinal axis and being in general longitudinal alignment.Adjacent raised elements are spaced along the longitudinal axis to thereby accommodatetissue displaced during passage of the penetrating member through tissue. Theraised elements are dimensioned to be generally atraumatic to tissue. The raisedelements may define an arcuate profile.
