The development and structure of the mesentery

Kevin Gerard Byrnes ,J Calvin Coffey,Ian S O’Brien,Domhnall M Coffey,Rosa M Mirapeix ,Jill P J M Hikspoors ,Mary E Luther,Hugh D Brady ,Colin Peirce ,Wouter H Lamers ,Leon Walsh ,Martin J Shelly,Shaoxiang Zhang ,Xiaoqin Zhang ,Timothy Scanlon ,Dara Walsh,Colum P Dunne,Yi Wu,Peter Dockery,Kieran W Mcdermott,Muhammad Fahad Ullah ,P A J Brama

doi:10.1038/s42003-021-02496-1

Abstract

The position of abdominal organs, and mechanisms by which these are centrally connected, are currently described in peritoneal terms. As part of the peritoneal model of abdominal anatomy, there are multiple mesenteries. Recent findings point to an alternative model in which digestive organs are connected to a single mesentery. Given that direct evidence of this is currently lacking, we investigated the development and shape of the entire mesentery. Here we confirm that, within the abdomen, there is one mesentery in which all abdominal digestive organs develop and remain connected to. We show that all abdominopelvic organs are organised into two, discrete anatomical domains, the mesenteric and non-mesenteric domain. A similar organisation occurs across a range of animal species. The findings clarify the anatomical foundation of the abdomen; at the foundation level, the abdomen comprises a visceral (i.e. mesenteric) and somatic (i.e. musculoskeletal) frame. The organisation at that level is a fundamental order that explains the positional anatomy of all abdominopelvic organs, vasculature and peritoneum. Collectively, the findings provide a novel start point from which to systemically characterise the abdomen and its contents.

Highlights

The position of abdominal organs, and mechanisms by which these are centrally connected, are currently described in peritoneal terms
The findings indicate that the anatomical foundation in the human abdomen, applies to a range of animal species
It is the organ in which all abdominal digestive organs develop and remain connected to

Summary

Introduction

The position of abdominal organs, and mechanisms by which these are centrally connected, are currently described in peritoneal terms. Recent findings point to an alternative model in which digestive organs are connected to a single mesentery. Within the abdomen, there is one mesentery in which all abdominal digestive organs develop and remain connected to. The organisation at that level is a fundamental order that explains the positional anatomy of all abdominopelvic organs, vasculature and peritoneum. Whilst there are suggestions these properties apply above the duodenum, direct evidence is lacking[4] If they held, it could alter our understanding of the organisation of abdominal contents in general. The findings illuminate the composition of the anatomical foundation of the abdomen, and the order at that level They explain the positional anatomy of all abdominal digestive organs (including that of the vasculature associated with these) and the organisation of the peritoneum

Methods

Results

Conclusion