The umbilicus and signs and symptoms of associated pathology
 The umbilicus and signs and symptoms of associated pathology:  The umbilicus represents the location of 4 fetal structures,   the  umbilical vein,   2 umbilical arteries, and   the urachus which is a tube extending  from the superior aspect of the bladder towards the umbilicus (it represents the  obliterated vesicourethral canal).  The urachus may remain open at various points leading to the  following abnormalities   Completely patent urachus: communicates with the bladder and leaks  urine through the umbilicus. Usually doesn't present until adulthood (strong  contractions of bladder of a child closes the mouth of the fistula).   Vesicourachal diverticulum:  a diverticulum in the dome of the  bladder. Usually symptomless.   Umbilical cyst or sinus:  can become infected, forming an abscess or  may chronically discharge infected material from the umbilicus. A cyst can  present as an immobile, midline swelling between the umbilicus and bladder, deep  to the rectu...