title: Principle of relative positioning of structures in the human body.
abstract: The arrangement of various biological structures should generally ensure the safety of crucial structures and increase their working efficiency; however, other principles governing the relative positions of structures in humans have not been reported. The present study therefore investigated other principles using nerves and their companion vessels in the human body as an example. Nerves and blood vessels usually travel together and in the most direct way towards their targets. Human embryology, histology, and gross anatomy suggest that there are many possible positions for these structures during development. However, for mechanical reasons, tougher or stronger structures should take priority. Nerves are tougher than most other structures, followed by arteries, veins, and lymphatic vessels. Nerves should therefore follow the most direct route, and be followed by the arteries, veins, and lymphatic vessels. This general principle should be applicable to all living things.
authors.affiliation: Department of Human Anatomy Histology and Embryology, Kunming Medical University, Kunming 650500, Yunnan Province, China.
authors.forename: Buliang
authors.initials: B
authors.lastname: Meng
authors.affiliation: Department of Neurology, First Affiliated Hospital of Kunming Medical University, Kunming 650032, Yunnan Province, China.
authors.forename: Ailan
authors.initials: A
authors.lastname: Pang
authors.affiliation: Department of Human Anatomy Histology and Embryology, Kunming Medical University, Kunming 650500, Yunnan Province, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Li
keywords: anatomy; histology; human embryology; neural regeneration; neuroregeneration; position; principle; reviews