Anorectal physiology and pathophysiology in the elderly.

Anorectal medical disorders facing the elderly include fecal incontinence, fecal impaction with overflow fecal incontinence, chronic constipation, dyssynergic defecation, hemorrhoids, anal fissure, and pelvic floor disorders. This article discusses the latest advances in age-related changes in morphology and function of anal sphincter, changes in cellular and molecular biology, alterations in neurotransmitters and reflexes, and their impact on functional changes of the anorectum in the elderly. These biophysiologic changes have implications for the pathophysiology of anorectal disorders. A clear understanding and working knowledge of the functional anatomy and pathophysiology will enable appropriate diagnosis and treatment of these disorders.