Interventional procedure consultation document

Percutaneous tibial nerve stimulation for faecal incontinence

Treating faecal incontinence by stimulating a nerve near the ankle

Faecal incontinence occurs when a person loses (often only partially) voluntary control of their bowel movements, resulting in leakage of faeces. The condition may relate to inadequate formation of the anus from birth. It can also relate to diseases of the nervous system (such as spina bifida, spinal cord injury, multiple sclerosis), pelvic organ prolapse, or previous pelvic surgery or radiotherapy. In women, another cause is injury to the anal canal during childbirth.

This procedure involves inserting a fine needle into a nerve just above the ankle and passing a mild electric current through the needle to the nerves that control bowel function.

The National Institute for Health and Clinical Excellence (NICE) is examining percutaneous tibial nerve stimulation for faecal incontinence and will publish guidance on its safety and efficacy to the NHS in England, Wales, Scotland and Northern Ireland. NICE’s Interventional Procedures Advisory Committee has considered the available evidence and the views of Specialist Advisers, who are consultants with knowledge of the procedure. The Advisory Committee has made provisional recommendations about percutaneous tibial nerve stimulation for faecal incontinence.

This document summarises the procedure and sets out the provisional recommendations made by the Advisory Committee. It has been prepared for public consultation. The Advisory Committee particularly welcomes:

• comments on the provisional recommendations
• the identification of factual inaccuracies
• additional relevant evidence, with bibliographic references where possible.

Note that this document is not NICE’s formal guidance on this procedure. The recommendations are provisional and may change after consultation.

The process that NICE will follow after the consultation period ends is as follows.

• The Advisory Committee will meet again to consider the original evidence and its provisional recommendations in the light of the comments received during consultation.
• The Advisory Committee will then prepare draft guidance which will be the basis for NICE’s guidance on the use of the procedure in the NHS in England, Wales, Scotland and Northern Ireland.

For further details, see the Interventional Procedures Programme manual, which is available from the NICE website (www.nice.org.uk/ipprogrammemanual).

NICE is committed to promoting through its guidance race and disability equality and equality between men and women, and to eliminating all forms of discrimination. One of the ways we do this is by trying to involve as wide a range of people and interest groups as possible in the development of our guidance on interventional procedures. In particular, we aim to encourage people and organisations from groups in the population who might not normally comment on our guidance to do so.

In order to help us promote equality through our guidance we would be grateful if you could consider the following question:

Are there any issues that require special attention in light of NICE’s duties to have due regard to the need to eliminate unlawful discrimination and promote equality and foster good relations between people with a characteristic protected by the equalities legislation and others?

Closing date for comments: 21 February 2011

Target date for publication of guidance: May 2011

1   Provisional recommendations

1.1  The evidence on percutaneous tibial nerve stimulation (PTNS) for faecal incontinence raises no major safety concerns. There is evidence of efficacy in the short term in a limited number of patients. Therefore, this procedure should only be used with special arrangements for clinical governance, consent and audit or research.

1.2  Clinicians wishing to undertake PTNS for faecal incontinence should take the following actions.

• Inform the clinical governance leads in their Trusts.
• Ensure that patients and their carers understand the uncertainty about the procedure’s efficacy and provide them with clear written information. In addition, the use of NICE’s information for patients (‘Understanding NICE guidance’) is recommended (available from www.nice.org.uk/IPGXXXpublicinfo). [[details to be completed at publication]]
• Audit and review clinical outcomes of all patients having PTNS for faecal incontinence (see section 3.1).

1.3  This procedure should be carried out only in units specialising in the assessment and treatment of faecal incontinence, as one of a range of treatment options.

1.4  The Committee was advised that further research is in progress. Future research should clearly define the patient groups being treated and should explicitly address treatment schedules. Studies should report long-term outcomes and requirements for retreatment. NICE may review this guidance on publication of further evidence.

2   The procedure

2.1  Indications and current treatments

2.1.1  Faecal incontinence occurs when a person loses the ability to control their anal sphincter and bowel movements, resulting in leakage of faeces. Causes include inadequate formation of the anus from birth, neurological disease, and perineal injury during vaginal delivery (a relatively common cause in women).

2.1.2  First-line treatment is conservative, with measures such as dietary management or antidiarrhoeal medication. If these are not successful, pelvic floor muscle or anal sphincter training (sometimes including biofeedback therapy) may be used.

2.1.3  In patients refractory to conservative treatment, surgical options include sphincter repair, sacral nerve stimulation, stimulated graciloplasty (creation of a new sphincter from other suitable muscles), anorectal or transabdominal implantation of an artificial anal sphincter, or permanent colostomy.

2.2   Outline of the procedure

2.2.1  The aim of PTNS is to achieve a neuromodulatory effect similar to that of sacral nerve stimulation through a less invasive route, but its exact mechanism of action is unclear.

2.2.2  A fine gauge needle is inserted percutaneously, just above and medial to the ankle, next to the posterior tibial nerve, and a surface electrode is placed near the arch of the foot. The needle and electrode are connected to a low-voltage stimulator. Stimulation of the posterior tibial nerve produces a motor (plantar flexion or fanning of the toes) and sensory (tingling in the ankle, foot or toes) response. Initial treatment usually consists of 12 outpatient sessions lasting 30 minutes each, typically a week apart.

Sections 2.3 and 2.4 describe efficacy and safety outcomes from the published literature that the Committee considered as part of the evidence about this procedure. For more detailed information on the evidence, see the overview, available at www.nice.org.uk/guidance/IP/877/overview

2.3   Efficacy

2.3.1  A non-randomised comparative study of 52 patients treated by PTNS or sham reported that 53% (17/32) had ‘good’ results, 31% (10/32) had ‘fair’ results and 16% (5/32) had ‘poor’ results after treatment with PTNS. No clinical improvement was reported in the 20 patients treated with sham. Clinical improvement was measured using a score ranging from 0 to 20, with 0 being perfect continence. Patients in the ‘good’ group had a reduction in mean score from 17.4 to 1.7 (p < 0.001), the ‘fair’ group had a reduction from mean 18.2 to 8.5 (p < 0.05) and the ‘poor’ group had a reduction from mean 18.6 to 14.8 (no significance reported).

2.3.2  The case series of 22 patients reported significant improvements in the emotional and vitality domains of the Short Form-36 questionnaire at 6 weeks and in all domains except vitality at 1 year (mean score increased from 64 to 83 for physical functioning and from 59 to 75 for social functioning; p < 0.05 for each).

2.3.3  The non-randomised comparative study of 52 patients reported that of those patients with any improvement in scores after PTNS, 30% (8/27) had a recurrence of symptoms during a mean follow-up of 22.3 months (3 and 5 patients were originally considered to have ‘good’ and ‘fair’ results respectively). Six patients had further treatment but 2 refused treatment.

2.3.4  The Specialist Advisers listed key efficacy outcomes as sustained improvement in continence (including where top-up therapy is required) measured as a reduction in weekly faecal incontinence episodes and quality of life.

2.4   Safety

2.4.1  The case series of 22 patients reported gastrodynia (stomach ache) 2–3 hours after treatment sessions which lasted for several hours in 2 patients, and leg numbness lasting 2 hours in 1 patient in the first treatment session only (none required medical intervention).

2.4.2  Transient discomfort or throbbing pain at the insertion site, redness or inflammation at or around the needle insertion site, and transient toe numbness were all reported in a case series of 30 patients (number of cases not reported).

2.4.3  A case series of 13 patients reported that 1 patient stopped treatment after 7 weeks because of a swollen and painful leg (no further details).

2.4.4  The Specialist Advisers listed anecdotal adverse events as haematoma and nerve injury.

2.5   Other comments

2.5.1  The Committee considered that PTNS might offer a simple and relatively non-invasive procedure for relieving faecal incontinence which could have a significant impact on quality of life, if further research supports its efficacy and helps to define the patients for whom it is most likely to be effective.

2.5.2  The Committee noted that the published studies included patients with a variety of different conditions and that not all patients had serious disability as a result of their symptoms. It also noted, however, that current research is addressing these issues. 

3   Further information

3.1  This guidance requires that clinicians undertaking the procedure make special arrangements for audit. NICE has identified relevant audit criteria and is developing an audit tool (which is for use at local discretion), which will be available when the guidance is published.

3.2  For related NICE guidance see www.nice.org.uk

Bruce Campbell

Chairman, Interventional Procedures Advisory Committee

January 2011

_{Personal data will not be posted on the NICE website. In accordance with the Data Protection Act names will be anonymised, other than in circumstances where explicit permission has been given.}

 _{It is the responsibility of consultees to accurately cite academic work in order that they can be validated.}