Medical Terminology Daily (MTD) is a blog sponsored by Clinical Anatomy Associates, Inc. as a service to the medical community. We post anatomical, medical or surgical terms, their 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.

You are welcome to submit questions and suggestions using our "Contact Us" form. The information on this blog follows the terms on our "Privacy and Security Statement" and cannot be construed as medical guidance or instructions for treatment.


We have 132 guests online


A Moment in History

Andreas Vesalius Bruxellensis (1514- 1564)

A Flemish anatomist and surgeon, Andreas Vesalius was born on December 31, 1514 in Brussels, Belgium. He is considered to be the father of the science of Anatomy. Up until his studies and publications human anatomy studies consisted only on the confirmation of the old doctrines of Galen of Pergamon (129AD - 200AD). Anatomy professors would read to the students from Galen's work and a demonstrator would point in a body to the area being described, if a body was used at all. The reasoning was that there was no need to dissect since all that was needed to know was already written in Galen's books. Vesalius, Fallopius, and others started the change by describing what they actually saw in a dissection as opposed to what was supposed to be there. 

Vesalius had a notorious career, both as an anatomist and as a surgeon. His revolutionary book "De Humani Corporis Fabrica: Libri Septem" was published in May 26, 1543. One of the most famous anatomical images is his plate 22 of the book, called sometimes "The Hamlet". You can see this image if you hover over Vesalius' only known portrait which accompanies this article. Sir William Osler said of this book "... it is the greatest book ever printed, from which modern medicine dates" 

After the original 1543 printing, the Fabrica was reprinted in 1555. It was re-reprinted and translated in many languages, although many of these printings were low-quality copies with no respect for copyright or authorship.

The story of the wood blocks with the carved images used for the original printing extends into the 20th century. In 1934 these original wood blocks were used to print 617 copies of the book "Iconaes Anatomica". This book is rare and no more can be printed because, sadly, during a 1943 WWII bombing raid over Munich all the wood blocks were burnt.

One interesting aspect of the book was the landscape panorama in some of his most famous woodcuts which was only "discovered" until 1903.

Vesalius was controversial in life and he still is in death. We know that he died on his way back from a pilgrimage to Jerusalem, but how he died, and exactly where he died is lost in controversy. We do know he was alive when he set foot on the port of Zakynthos in the island of the same name in Greece. He is said to have suddenly collapsed and die at the gates of the city, presumably as a consequence of scurvy. Records show that he was interred in the cemetery of the Church of Santa Maria delle Grazie, but the city and the church were destroyed by an earthquake and Vesalius' grave lost to history. Modern researchers are looking into finding the lost grave and have identified the location of the cemetery. This story has not ended yet.

For a detailed biography of Andreas Vesalius CLICK HERE.

Personal note: To commemorate Andrea Vesalius' 500th birthday in 2014, there were many scientific meetings throughout the world, one of them was the "Vesalius Continuum" anatomical meeting on the island of Zakynthos, Greece on September 4-8, 2014. This is the island where Vesalius died in 1564. I had the opportunity to attend and there are several articles in this website on the presence of Andreas Vesalius on Zakynthos island. During 2015 I also attended a symposium on "Vesalius and the Invention of the Modern Body" at the St. Louis University. At this symposium I had the honor of meeting of Drs. Garrison and Hast, authors of the "New Fabrica". Dr. Miranda


 "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”.

Click here for more information


 

Rare & Collectible Books at AbeBooks.com 

bookplateink.com

Rectum

Anterior view of the rectum
Click for a larger image


The rectum is the most distal segment of the large intestine, along with the anal canal.

The word [rectum] arises from the Latin [rectus] and means "straight", such as its use in the name "rectus abdominis" for the "straight muscle of the abdomen".

It seems a misnomer, as the rectum of the human species is actually "S" shaped, as seen in the accompanying image. The reason for this discrepancy is that the rectum was named by Galen of Pergamon (129AD - 200 AD) who himself studied this structure in animals such as sheep and goats. In these animals the rectum is indeed straight, and since contradicting Galen was not acceptable (see Michael Servetus), the name has survived until this day. Even Andreas Vesalius has in his 1953 "Fabrica" a depiction of a straight rectum in the human! Click on second image to see a larger depiction of Vesalius' idea of the rectum. Although Vesalius stated that he wanted to show human anatomy as it is, and not as Galen said it should be, here is a demonstration that in 1543 he was still a lukewarm Galenist.

There is an area between the sigmoid and the rectum called the sigmoidorectal junction, although most anatomists call it (wrongly) the rectosigmoid junction (RSJ). This is an anatomically diffuse area with no clear anatomical transition between the sigmoid and the rectum or the RSJ from the rectum.

Rectum (Vesalius, 1543)
Click for a larger image

As the proximal end of the  "S" shaped rectum is not clearly discernible from the sigmoidorectal region, there is no clear agreement on the length of the rectum. Authors state that it measures approximately six to seven inches in length (15 - 17 cm), while others measure it as between 8-10 inches. The rectum  ends distally at the junction of the rectum with the  pelvic diaphragm. It is at this point that the anal canal begins.

The rectum is characterized by three transverse rectal folds, one on the right side, and two on the left side. These folds are know as the "rectal valves" or the "valves of Houston". The middle rectal fold is known to European anatomists as the "valve of  Kohlrausch" Their function in maintaining fecal material in place as well as their function in defecation is still under study. The rectal valves also have a high level of anatomical variation and may not be present at all.

Images:
1. "Tratado de Anatomia Humana" Testut et Latarjet 8 Ed. 1931 Salvat Editores, Spain
2. "De Humani Corporis Fabrica, Libri Septem" A. Vesalius 1543 Brussels 
Recommended reading: "Transverse Folds of Rectum: Anatomic Study and Clinical Implications" Shafik, A, et al. Clin Anat 14: 196-203 (2001).