What is Rectal incontinence is due to involvement of :a) External anal sphincterb) Internal anal sphincterc) Ischiococcygeusd) Pubococcygeus and explain in detail?
Rectal continence depends solely on the anorectal ring and any damage to this ring results in rectal incontinence.
The anorectal ring is a muscular ring present at the anorectal junction, and formed by the fusion of -

Puborectalis (a part of pubococcygeus which in turn is a part of levator ani)
Deep external anal sphincter
Internal anal sphincter

The puborectalis muscle appears to be the most important muscle for maintaining fecal continence.