Etiology and management of fecal incontinence

Abstract

Fecal incontinence is a challenging condition of diverse etiology and devastating psychosocial impact. Multiple mechanisms may be involved in its pathophysiology, such as altered stool consistency and delivery of contents to the rectum, abnormal rectal capacity or compliance, decreased anorectal sensation, and pelvic floor or anal sphincter dysfunction. A detailed clinical history and physical examination are essential. Anorectal manometry, pudendal nerve latency studies, and electromyography are part of the standard primary evaluation. The evaluation of idiopathic fecal incontinence may require tests such as cinedefecography, spinal latencies, and anal mucosal electrosensitivity. These tests permit both objective assessment and focused therapy. Appropriate treatment options include biofeedback and sphincteroplasty. Biofeedback has resulted in 90 percent reduction in episodes of incontinence in over 60 percent of patients. Overlapping anterior sphincteroplasty has been associated with good to excellent results in 70 to 90 percent of patients. The common denominator between the medical and surgical treatment groups is the necessity of pretreatment physiologic assessment. It is the results of these tests that permit optimal therapeutic assignment. For example, pudendal nerve terminal motor latencies (PNTML) are the most important predictor factor of functional outcome. However, even the most experienced examiner's digit cannot assess PNTML. In the absence of pudendal neuropathy, sphincteroplasty is an excellent option. If neuropathy exists, however, then postanal or total pelvic floor repair remain viable surgical options for the treatment of idiopathic fecal incontinence. In the absence of an adequate sphincter muscle, encirclement procedures using synthetic materials or muscle transfer techniques might be considered. Implantation of a stimulating electrode into the gracilis neosphincter and artificial sphincter implantation are other valid alternatives. The final therapeutic option is fecal diversion. This article reviews the current status of the etiology and incidence of incontinence as well as the evaluation and treatment of this disabling condition.