Disorder from the Middle Ages

X was a social phenomenon that occurred primarily in mainland Europe between 14th and 17th centuries. It involved groups of people ____ erratically.

One of the first major outbreaks was in Aachen, Germany, in 1374, and it quickly spread throughout Europe; one particularly notable outbreak occurred in Strasbourg in 1518.

The term X was coined by Paracelsus, and the condition was initially considered a curse sent by a saint, usually St John the Baptist or St Vitus
What is X?

Is it really worth it?

The human X averages 9 cm in length but can range from 2 to 20 cm. The diameter of the X is usually between 7 and 8 mm. The base of the X is located 2 cm beneath the ileocecal valve that separates the large intestine from the small intestine. Its position within the abdomen corresponds to a point on the surface known as McBurney's point. The X, therefore, may act as a "safe house" for commensal ("good") bacteria. This reservoir of gut flora could then serve to repopulate the digestive system following a bout of dysentery or cholera.

Y a medical emergency occurs when the X becomes blocked, often by stool, a foreign body, or cancer. Blockage may also occur from infection, since the X swells in response to any infection in the body. Left untreated, an inflamed X will eventually burst, or perforate, spilling infectious materials into the abdominal cavity.
Extra Trivia:The longest X ever removed measured 26 cm from a patient in Zagreb, Croatia.