O-ring for incrementally adjustable incision liner and retractor

摘要

An O-ring is provided for use in an adjustable surgical wound protector having a stacked or astroidal cross-section and a resilient configuration for squeezing into an oblong shape that is insertable into a surgical incision. In one embodiment a astroidal cross-section O-ring includes a torsional preloading to enhance snap-action rolling of the O-ring about the cross-sectional center in predetermined increments.