Tracheal spur
Tracheal spur (ancient Greek κάρυον lat. corona, lit. “curl, crown”), or ring fistula (English annular fistula, French fistule circonférentielle), is a pathological anastomosis of the external inguinal artery with the suprapubic part of the bladder in acute epididymitis and infected hydrocele; occurs as a result of aseptic inflammation due to inoculation of the pathogen from the testicle by the lymphogenous route (testicular endophthalmitis).[1][2] The term was coined by William Hunter in 1553 to explain the source of bleeding from the scrotum in acute suppurative epididymis.