Interventional procedure consultation document

Selective dorsal rhizotomy for spasticity in cerebral palsy

 The aim of selective dorsal rhizotomy is to ease muscle rigidity and improve mobility in people with cerebral palsy. It involves cutting nerves in the lower spine that are responsible for muscle rigidity.

The National Institute for Health and Clinical Excellence (NICE) is examining selective dorsal rhizotomy for spasticity in cerebral palsy 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 selective dorsal rhizotomy for spasticity in cerebral palsy.

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• The Advisory Committee will then prepare draft guidance which will be the basis for NICE’s guidance on the use of the procedure in the NHS in England, Wales, Scotland and Northern Ireland.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. We also ask consultees to highlight any ways in which draft guidance fails to promote equality or tackle discrimination and give suggestions for how it might be improved. NICE reserves the right to summarise and edit comments received during consultations, or not to publish them at all, where in the reasonable opinion of NICE, the comments are voluminous, publication would be unlawful or publication would otherwise be inappropriate.

Closing date for comments: 27 July 2010

Target date for publication of guidance: December 2010

1   Provisional recommendations

1.1  Current evidence on selective dorsal rhizotomy for cerebral palsy shows a small incidence of complications that are serious but well‑recognised.  The evidence on efficacy is adequate. Therefore this procedure may be used provided that normal arrangements are in place for clinical governance and audit.

1.2  During the consent process parents or carers should be informed that selective dorsal rhizotomy for cerebral palsy is irreversible, and that a small proportion of patients may suffer permanent bladder dysfunction with urinary incontinence as a result of this procedure. 

1.3  Patient selection should be carried out by a multidisciplinary team with specialist expertise in the treatment of spasticity in patients with cerebral palsy. This team would normally include a physiotherapist, a paediatrician and a neurosurgeon.

2   The procedure

2.1  Indications and current treatments

2.1.1  Cerebral palsy describes a group of permanent brain disorders that originate during fetal development, birth or early childhood. It is associated with abnormalities of movement, balance and posture, and people with cerebral palsy may also have language and visual difficulties. Lower limb spasticity affects 80% of people with cerebral palsy. This can impair walking and sitting, and can cause discomfort, cramps, spasms and pressure ulcers.

2.1.2  Current treatments for lower limb spasticity include oral muscle relaxant medication, orthotic devices, physiotherapy, repeated intramuscular injections of botulinum toxin, corrective orthopaedic procedures such as tendonotomy, electrical stimulation of the muscles or dorsal cord, and continuous intrathecal baclofen infusion. Surgical procedures such as tendon lengthening and osteotomy can also be used.

2.2   Outline of the procedure

2.2.1  The aim of selective dorsal rhizotomy is to achieve a long-term reduction in sensory input to the sensory–motor reflex arcs responsible for increased muscle tone, by dividing some of the lumbar sensory nerve roots, while leaving the motor nerves affecting voluntary movements.

2.2.2  With the patient under general anaesthesia, a laminectomy of one or more vertebrae is performed to expose the dural sac, which is opened to display the cauda equina. Intra-operative neurophysiological assessment is performed to identify the sensory nerve rootlets judged to be most responsible for the excess motor tone. These rootlets are selectively divided, while preserving nerve roots responsible for voluntary movements. 

2.2.3  Physiotherapy may be needed for several months after the procedure. Patients who were previously able to walk may have to learn different walking skills.

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/IP318boverview

2.3   Efficacy

2.3.1  A non-randomised comparative study of 142 patients treated by the procedure (n = 71) or intrathecal baclofen pumps (ITBP) (n = 71) reported improved Modified Ashworth Scale scores (measures spasticity and improvement in muscle tone on a scale from 0 to 5; lower score indicates less increase in muscle tone) of −2.52 and −1.23 points respectively at 1-year follow-up (p < 0.0001).

2.3.2  A meta-analysis of 3 randomised controlled trials including a total of 90 patients treated by the procedure plus physiotherapy or by physiotherapy alone reported that Gross Motor Function Measure (GMFM) scores (evaluates change in gross motor function in children with cerebral palsy) improved by 8% and 4% respectively at 9-month follow-up (1 study) and 12-month follow-up (2 studies) (p = 0.008) (absolute figures not stated).

2.3.3  A non-randomised comparative study of 108 patients treated by the procedure and physiotherapy or by physiotherapy alone reported mean improvements in GMFM score (higher score indicates better gross motor functioning) from baseline of 87 to 92 and 89 to 91 respectively at 20-month follow-up (p < 0.05 for both groups from baseline).

2.3.4  The non-randomised comparative study of 142 patients treated by the procedure or ITBP reported that 94% and 96% of patients respectively were satisfied at 1-year follow-up (absolute figures not stated) (p = 0.71).

2.3.5  The Specialist Advisers listed key efficacy outcomes as reduction in lower limb spasticity, reduction in number of subsequent orthopaedic procedures, improved gross motor function, improved gait and walking, improved level of independence and quality of life. 

2.4   Safety

2.4.1  Urinary incontinence was reported in 5% (1/21) of patients treated by the procedure plus physiotherapy in the non-randomised comparative study of 42 patients (not otherwise described).

2.4.2  Radiologically observed scoliosis was reported in 9% (5/58) of patients who had laminectomy and 1% (2/150) of patients who had laminoplasty in the case series of 208 patients at a mean follow-up of 4.2 years. The percentage of patients with scoliosis pre-operatively was not stated.

2.4.3  A case series of 61 patients reported on 10 patients with lumbar hyperlordosis (accentuation of the lumbar curve) after the procedure (1 patient had this condition at baseline). An increase in the mean angle of hyperlordosis from 17.9° at baseline to 29.3° at a mean follow-up of 6.3 years was reported (p < 0.05). Four patients developed spondylolysis and grade-I spondylolisthesis between 3 and 5 years after the procedure and 1 patient developed lumbar kyphosis 7 years after the procedure.

2.4.4  Urinary retention due to decreased bladder tone and hyporeflexia was reported in 10% (20/208) of patients in the case series of 208 patients. This resolved spontaneously within 4 weeks in 18 patients but 2 patients had long-term urinary incontinence because of atonic bladder.

2.4.5  The Specialist Advisers considered theoretical adverse events to include death, worsening motor function and/or paraplegia, wound infection, meningitis, cerebrospinal fluid leakage, dislocation of the hip(s), back pain, constipation, weakness, chronic pain, and late arachnoiditis and/or syringomyelia.

3   Further information

3.1  This guidance is a review of ‘Selective dorsal rhizotomy for spasticity in cerebral palsy’ NICE interventional procedures guidance 195 (2006).

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

Bruce Campbell

Chairman, Interventional Procedures Advisory Committee
July 2010

_{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.}