What is faecal incontinence?
Faecal incontinence is defined as the involuntary loss of solid or liquid stool that causes a social or hygienic problem. It is a distressing condition that people can be reluctant to seek medical attention for. It is thought that at least ½ million UK adults suffer persistent faecal incontinence of varying degrees of severity, ranging from uncontrolled release of gas to complete loss of control. Faecal incontinence is significantly more common in women; the reasons for this include the fact that females have a shorter anal canal then males and the sphincter mechanism is commonly altered by obstetric trauma.
What causes faecal incontinence?
There are a number of different causes of faecal incontinence; often the cause is multi-factorial. Factors include a loose stool consistency, either due to dietary factors or bowel pathology (e.g. inflammatory bowel disease), neurological problems affecting normal anal sphincter control, sphincter weakness or damage, interfering factors in the normal continence mechanisms (e.g. haemorrhoids, rectal prolapse, tumours), or severe constipation resulting in faecal impaction.
Assessment of faecal incontinence
A good history and a careful clinical examination remain the cornerstone of the assessment of faecal incontinence; however, your surgeon may wish to use one or all of the following investigations in order to optimise assessment and treatment planning:
- Endoanal ultrasound – an ultrasound probe is used to determine the anatomy of the anal sphincter complex.
- Anorectal physiology – a different probe allows measurement of the pressure changes within the anal canal, giving a functional assessment of the sphincter muscles.
- Flexible sigmoidoscopy or colonoscopy – to directly visualize the bowel lining to rule out bowel pathology.
Treatment is often focused around simple measures to either thicken the stool consistency (e.g. dietary modification, use of bulking agents) or strengthen the anal sphincter muscles (pelvic floor exercises). Sometimes, surgery is indicated; this is usually only after extensive investigation and might include:
- Sacral nerve stimulation – a small wire is inserted into the back, adjacent to the sacral nerves that control the anal sphincter muscles, causing them to be more effective. The wire is connected to a small battery pack that is placed surgically under the tissues of the buttock.
- Sphincter repair – rarely, surgical repair of a defective anal sphincter muscle is appropriate.