The word [torus] is of Latin origin and refers to “a rounded protuberance or swelling”. In science, it refers to a doughnut-shaped structure (see image). It also refers to the rounded, bulging, and circular base component of a pillar, found between the square plinth and the main body of the pillar. The torus can be seen in Egyptian, Greek, and Roman style pillars.

The term is used in anatomy and medicine to denote normal or abnormal circular or semicircular protuberances, as in the case of the “torus tubarius”, a normal semicircular elevation found at the ostium of the auditory tube (of Eustachius) in the lateral walls of the rhinopharynx. The torus tubarius elevation is due to the presence of lymphoid tissue which can get inflamed.

Click on the image for a larger view

In orthopedics it is used to denote a compression fracture where the cortex of a long bone close to one of its epiphyses buckles under longitudinal (axial) compression. The look of the fracture is similar to the location of the torus in a pillar. An example of this is the torus fracture (also known as buckle fractures) in children.

The term [torulus] is related to [torus], as it means a “small torus” and it refers to a small elevation, which is synonymous with the word “papilla”. An example of this is the term torulus tactiles palmaris, referring to small elevations on the palms of the hand. Another related term is [torulosis], referring to a large number of small elevations or pimples.

The following images are of a Greek pillar taken in 2014 in Athens showing the location of the torus. The next image shows a torus fracture. The image is from www.kidsfractures.com/forearm/ and we thank them for sharing the image with us. This is a great site for information on fractures in children.

Click on the image for a larger view

Click on the image for a larger view

Sources:
1. “Medical Meanings: A Glossary of Word Origins” Haubrich, WS. Am Coll Phys. Philadelphia 1997
2. “The Origin of Medical Terms” Skinner, HA 1970, New York. Hafner Publishing Company
3. “Taber’s Cyclopedic Medical Dictionary” 16th Ed. 1989. Philadelphia. FA Davis Company
4.  www.kidsfractures.com/forearm/

Torus image: By LucasVB [Public domain], via Wikimedia Commons

Thanks to Jackie Miranda-Klein for suggesting this post. Jackie is studying for the Physician Assistant Master's degree at Kettering College. Dr. Miranda.