A surgical instrument includes a first member that has an opening in its distal region for admitting tissue and that is rotatable with respect to a base from which {HEAD ~ the first member} extends to allow {TAIL ~ the rotational orientation} of the opening to be selectively changed with respect to the axis of the instrument 
extends to allow
A surgical instrument includes a first member that has an opening in its distal region for admitting tissue and that is rotatable with respect to a base from which { HEAD ~ the first member } extends to allow { TAIL ~ the rotational orientation } of the opening to be selectively changed with respect to the axis of the instrument
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH