Sacral neuromodulation in the treatment of defecation disorders

A large number of patients present with fecal incontinence due to idiopathic pelvic neuropathy or lesions of pelvic nerves, iatrogenic or secondary to other pelvic diseases or dysfunctions, involving sacral nerves. On the other hand, in many patients, constipation could be related to a peripheral neuropathy impairing normal defecation. Sacral neuromodulation (SNM) has been demonstrated as an effective approach in neuropathic defecation disorders. Its application is usually safe and easy, with a limited rate of complications or adverse events. The surgical procedure is made under local anesthesia. SNM effectiveness can be reliably tested during a short term period (up to 30 days) before the decision for a permanent implant. Results in most series show significant clinical improvement, with reduction in the number of incontinence episodes, decrease of incontinence score and improvement in patients' quality of life. A few reports suggest a potential and interesting application of SNM in constipation. Findings from anorectal manometry and other physiology examinations are not conclusive in order to define SNM mechanisms of actions and suggest that a multifactorial effect "modulates" the deficient neuromuscular system causing the defecation disorders.