The anatomy of the distal urinary tract

 

W. Dorschner, J.-U. Stolzenburg, J. Mondry

 

The storing and voiding of urine is a cycle which is repeated many thousands of times - from the first wet nappy of a baby to the cessation of all vital functions – only drawing attention to itself when a fateful development disturbs the harmony of structure and function. An exact knowledge of the anatomy and the physiology of the lower urinary tract is essential for the treatment of the subsequent urological dysfunction.

 

„He who is most amazed at the fact that the much discussed question has become again object of the anatomic inquiry is asked to read the specialist literature on anatomy and physiology of the urinary bladder; in that case he will be surprised, and rightly so.“ (Heiss, 1928)

 

The proposed three-dimensional model of the anatomy of the distal urinary tract is based exclusively on our own histomorphological studies. For the first time the organs of the lower urinary tract of both genders and all age groups were analysed. In this way, anatomic findings have been obtained from 30,000 histomorphological serial autopsies.

 

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At present it is generally agreed that a fundamental condition for urinary continence is the extent to which the maximum bladder capacity is limited by the elastic potential of the detrusor. In general the musculus sphincter urethrae is considered to be the main factor for the urinary continence. This, however, raises the question how a supposedly striated and therefore voluntarily innervated muscle is able to ensure a continuos continence.