Medical Terminology Daily (MTD) is a blog sponsored by Clinical Anatomy Associates, Inc. as a service to the medical community, medical students, and the medical industry. We will post a workweek daily medical or surgical term, its meaning and usage, as well as biographical notes on anatomists, surgeons, and researchers through the ages. Be warned that some of the images used depict human anatomical specimens.

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A Moment in History

Antoine Louis

French surgeon, anatomist, and physiologist. Following his medical studies and a long career as a physiologist, Antoine Louis was named Permanent Secretary of the Royal French Academy of Surgery. His other titles were those of Professor of the Royal Academy, Consultant Surgeon of the Armies of the King, member of the Royal Society of Sciences of Montpellier, Inspector of the Royal Military Hospitals, and Doctor in Law of the University of Paris. As a member of these academies Louis was instrumental in the design and construction of the guillotine. Initially called the "Louisette", this device was later named after another French physician in the same committee, Dr. Joseph-Ignace Guillotin.

Antoine Louis' name is better know to history as the eponymic origin of the "sternal angle" also know as the "Angle of Louis" and synonymously (probably by misspelling or translation) the "angle of Lewis", and "angle of Ludwig". This anatomical landmark is extremely important as it serves as a superficial landmark for important anatomical occurrences (click here).

As a point of controversy, there are some that contest the history of this eponym adjudicating it to Pierre Charles Alexander Louis (1787-1872), another French physician dedicated to the study of tuberculosis.

1. Srickland, N; Strickland A Angle of Louis, More Than Meets the Eye. MedTalks:
2. Ramana, R. K., Sanagala, T. and Lichtenberg, R. (2006), A New Angle on the Angle of Louis. Congestive Heart Failure, 12: 197–199
. "The origin of Medical Terms" Skinner, HA; 1970

 "Clinical Anatomy Associates, Inc., and the contributors of "Medical Terminology Daily" wish to thank all individuals who donate their bodies and tissues for the advancement of education and research”.

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The  word [cathedra] is Greek, from [καθέδρα] meaning "a high chair",  a "teacher's chair" or a "throne". The term was later accepted into Latin with the same meaning.

In the early pre-Vesalian days of anatomy, the teachers would seat in a high-chair or cathedra from where they would read the anatomy from a book while a prosector or demonstrator would dissect, expose and point to the structures. The professor would not consider coming down from the cathedra to discuss the anatomy shown. This was changed by Andreas Vesalius who did the dissections and demonstrations himself, using the books as reference or to prove a point.

The term cathedra has been brought to our times, where we refer to the position at the head of a group as the "Chair": Chair of the Science Department, Chair of Surgery, etc.

The word cathedra was used to refer to a Bishop's chair in a church, so that large churches (which had a bishop) are now known as [cathedrals]. It is also said that someone of authority speaking in uncontestable terms is speaking ex-cathedra (from the chair)

Title page of Anathomia Corporis Humanis by Mondino de Luzzi. Image courtesy of the National Library of Medicine
Title page of Anathomia Corporis Humanis by Mondino de Luzzi
In other languages the term "cathedratic" means a teacher in a high position, while in English the term refers to a Bishop speaking from the chair.

The image in this article is a close up of the title page of Mondino de Luzzi’sAnothomia Corporis Humani” published in 1478. The person on the image could be Alessandra Giliani (1307 - 1326) who is at the foot of the cathedra following the directions of Mondino de Luzzi. Click on the image for a complete depiction of the title page.

Original image courtesy of NLM