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