PURPOSE: Basic scientific facts, such as anatomical structures, are rarely subjected to critical reappraisal. Nevertheless, several clinical phenomena exist which are inconsistent with the description of the anatomy of the so-called external sphincter muscle and urogenital diaphragm. MATERIALS AND METHODS: We performed a global examination of the anatomy of the entire lower urinary tract in 50 male autopsy specimens. For comparison magnetic resonance imaging of the same regions was performed on 12 healthy patients. RESULTS: Direct comparison of the results of both methods revealed the exact same topography of the bladder neck. The external sphincter or musculus sphincter urethrae is an independent morphological unit separated from the surrounding pelvic floor muscles by connective tissue. CONCLUSIONS: The musculus transversus perinei profundus or deep transverse perineal muscle, which is believed to constitute the major element of the urogenital diaphragm, does not exist. There is histomorphological evidence that the external sphincter consists of a striated (musculus sphincter urethrae transversostriatus) and smooth muscle (musculus sphincter urethrae glaber) component.
PURPOSE: Basic scientific facts, such as anatomical structures, are rarely subjected to critical reappraisal. Nevertheless, several clinical phenomena exist which are inconsistent with the description of the anatomy of the so-called external sphincter muscle and urogenital diaphragm. MATERIALS AND METHODS: We performed a global examination of the anatomy of the entire lower urinary tract in 50 male autopsy specimens. For comparison magnetic resonance imaging of the same regions was performed on 12 healthy patients. RESULTS: Direct comparison of the results of both methods revealed the exact same topography of the bladder neck. The external sphincter or musculus sphincter urethrae is an independent morphological unit separated from the surrounding pelvic floor muscles by connective tissue. CONCLUSIONS: The musculus transversus perinei profundus or deep transverse perineal muscle, which is believed to constitute the major element of the urogenital diaphragm, does not exist. There is histomorphological evidence that the external sphincter consists of a striated (musculus sphincter urethrae transversostriatus) and smooth muscle (musculus sphincter urethrae glaber) component.
Authors: Miguel Ramírez-Backhaus; Robert Rabenalt; Sunjay Jain; Minh Do; Evangelos Liatsikos; Roman Ganzer; Lars-Christian Horn; Martin Burchardt; Fernando Jiménez-Cruz; Jens-Uwe Stolzenburg Journal: World J Urol Date: 2008-12-10 Impact factor: 4.226
Authors: Michael Kim; Shawna L Boyle; Alfonso Fernandez; Edward D Matsumoto; Kenneth T Pace; Maurice Anidjar; Gregory N Kozak; Sumit Davé; Blayne K Welk; Marjorie I Johnson; Stephen E Pautler Journal: Can Urol Assoc J Date: 2014-11 Impact factor: 1.862