The internal anal sphincter can not close the anal canal completely

✍ Scribed by B. Lestar; F. Penninckx; H. Rigauts; R. Kerremans

• Book ID: 104738738
• Publisher: Springer
• Year: 1992
• Tongue: English
• Weight: 401 KB
• Volume: 7
• Category: Article
• ISSN: 0179-1958
• DOI: 10.1007/bf00360358

✦ Synopsis

We determined the maximum closing capability of the internal anal sphincter muscle ring in vitro and in vivo. The internal sphincter, 4 to 6 mm thick, cannot close the anal canal hermetically, not even during maximal contraction. The blood-filled anal cushions have to fill up an intrasphincteric gap of at least 7 to 8 mm in diameter.