Internal anal sphincter is composed more of smooth muscle and is under parasympathetic/sympathetic control, while external anal sphincter is skeletal muscle and controlled by pudendal nerve. All of the other muscles listed are skeletal muscle of the pelvic floor and are more likely to be involved in Kegel exercises.
charcot_bouchardWhen i faced this ques i did some Kegel. Felt something in my pee pee but not in my b*e. I exclude all option because they are bigger muscle of pelvic floor except EUS & IAS. And also remeber Kegel can be used as a treatment of prem. ejaculation not premature defication.+18
paperbackwriter@charcot_bouchard Actually Kegels are used in the treatment of fecal incontinence as well because of effect on EXTERNAL anal sphincter and surrounding muscles which are under voluntary control (you can most definitely feel it if you do a kegel lol). The answer is internal anal sphincter because internal is not under voluntary control (tonically contracted via symp. --> parasymp. relaxes it --> gotta go feeling --> no incontinence because of external sphincter's voluntary contraction). +12
am4140@paperbackwriter - Honestly, this depends on how you do the kegel. It is entirely possible to not involve your external anal sphincter at all once you figure out how to isolate your vaginal area. So the internal anal sphincter is under involuntary control so that was especially right, but I was prepared to pick anything with โanalโ in it at all.
So kegels work for fecal incontinence only if youโre choosing to involve your external anal sphincter, or you donโt know how or are too inexperienced to isolate the muscles around your vagina. I donโt think NBME or USMLE would get this tricky because the external anal sphincter will not always be involved in kegels. +1
thesmexynevusI wonder how many kegels you did while reading this.+1
submitted by โneonem(629)
Internal anal sphincter is composed more of smooth muscle and is under parasympathetic/sympathetic control, while external anal sphincter is skeletal muscle and controlled by pudendal nerve. All of the other muscles listed are skeletal muscle of the pelvic floor and are more likely to be involved in Kegel exercises.