{HEAD ~ Joints} between the fourchette and {TAIL ~ the anterior and posterior portions} maintain an opening formed by the cuff in an open position 
between
{ HEAD ~ Joints } between the fourchette and { TAIL ~ the anterior and posterior portions } maintain an opening formed by the cuff in an open position
HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH