Functional Electrical Stimulation During Walking in Cerebral Palsy

Functional Electrical Stimulation of the Ankle Dorsiflexors During Walking in Children With Unilateral Spastic Cerebral Palsy: a Randomized Crossover Intervention Study

Children with spastic cerebral palsy (CP) often walk with insufficient ankle dorsiflexion in the swing phase. A pathological gait, known as drop-foot gait, can be the result and this has 2 major complications: foot-slap during loading response and toe-drag during swing. This is partly caused by weakness of the anterior tibial muscle and partly due to co-contraction of both the fibular- and anterior tibial muscle. For classification of gait, the Winters scale can be used, where unilateral CP with dropfoot is classified as type I.

In daily life these problems cause limited walking distance and frequent falls, leading to restrictions in participating in daily life. The current guideline for spastic cerebral palsy describes the following therapies: 1) conservative therapy (physiotherapy, orthopaedic shoes and orthoses) 2) drugs suppressing spasticity 3) surgical interventions.

Functional electrical stimulation (FES) may be an effective alternative treatment for children with spastic CP and a drop foot. By stimulating the fibular nerve or the anterior tibial muscle directly during the swing phase, dorsiflexion of the foot is stimulated. In contrast to bracing, FES does not restrict motion, but does produce muscle contraction, and thus has the potential to increase strength and motor control through repetitive neural stimulation over time.

In a systematic review the investigators found that FES immediately improves ankle dorsal flexion and reduces falls and these effects also sustain. However, it should be noted that the level of evidence is limited. Until now, the use of FES in CP is limited and no data exist about the effects on walking distance (activity level) and participation level.

The overall objective of this study is to conduct a randomised cross-over intervention trial in children with unilateral spastic CP with 12 weeks of FES (for every participant) and 18 weeks of conventional therapy. The effectiveness of FES will be examined at participation leven, using individual goal attainment. Next to that the effect at gait will be measured. An additional goal is to investigate the cost effectiveness of FES, which, in case of a positive effect, may support allowance by insurance companies.

Study Overview

• Status: Completed
• Conditions: Cerebral Palsy; Foot Drop; Spastic
• Intervention / Treatment: Device: FES

Detailed Description

Children with spastic cerebral palsy often walk with insufficient ankle dorsiflexion in the swing phase or with eversion of the foot. A pathological gait, known as drop-foot gait, can be the result and this has 2 major complications: foot-slap during loading response and toe-drag during swing. This is partly caused by weakness of the anterior tibial muscle and partly due to co-contraction of both the fibular- and anterior tibial muscle. In time, the disorder appears to be progressive due to atrophy and contractures of the muscle and increasing bodyweight. For classification of gait, the Winters scale can be used, where unilateral CP with dropfoot is classified as type I.

In daily life these problems cause limited walking distance and frequent falls. This can lead to restrictions in participating in daily activities at school and in leisure. The current guideline for spastic cerebral palsy describes the following therapies: 1) conservative therapy, which includes physiotherapy, orthopaedic shoes and orthoses. 2) systemically and locally applied drugs suppressing spasticity. 3) surgical interventions, e.g. tenotomy, transposition and osteotomy. In each intervention, there is the risk of side effects, such as sedation with oral medications, pressure sores and atrophy in a static orthosis, temporary effect in a Botulinum toxin A treatment and surgical complications due to a result of the surgery, and on the other hand as a result of the execution.

Functional electrical stimulation (FES) may be an effective alternative treatment for children with spastic CP and a drop foot. By stimulating the fibular nerve or the anterior tibial muscle directly during the swing phase, dorsiflexion of the foot is stimulated. In contrast to bracing, FES does not restrict motion, but does produce muscle contraction, and thus has the potential to increase strength and motor control through repetitive neural stimulation over time.

In a systematic review the investigators found that FES immediately improves ankle dorsal flexion and falls. In addition, longer sustained effects of FES on ankle dorsal flexion and falls are found. However, it should be noted only two study studies (4 articles) were of level II class evidence (small RCT) and all other studies used a single subject design. Until now, the use of FES in CP is limited and no data exist about the effects on walking distance (activity level) and participation level.

The overall objective of this study is to conduct a randomised cross-over intervention trial in children with unilateral spastic CP with 12 weeks of FES for every participant and 18 weeks of conventional therapy. The effectiveness of FES will be examined at participation leven, using individual goal attainment. With every individual a goal at walking distance will be set, next to possible other goals. Next to that, results will be measured at the activity and functional level: the effect at gait kinematics (such as ankle dorsiflexion and balance), walking distance, falls, spasticity and muscle force. The type of brain damage of the patients is also taken in to account. An addition al goal is to investigate the cost effectiveness of FES, which, in case of a positive effect, may support allowance by insurance companies.

• Study Type: Interventional
• Enrollment (Actual): 25
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Netherlands
  • Limburg
    • Maastricht, Limburg, Netherlands, 6229 HX
      • Maastricht University Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 4 years to 18 years (Child, Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Unilateral foot drop of central origin, particularly the absence of initial heel contact
• Participants are currently treated with ankle-foot orthoses or (adapted) shoes to wear on a daily basis
• Participants ambulate independently, and thus classified as Gross Motor Function Classification System (GMFCS) levels I or II and have a gait type 1 according to Winters et al (4).
• Participants are able to walk for at least 15 minutes
• Confirmed cerebral abnormality with MRI (showing medial infarction, maldevelopment of the brain, or porencephaly).
• Participants are aged 4-18 years at time of inclusion

Exclusion Criteria:

• Plantarflexion ankle contracture of more than 5 degrees plantarflexion with the knee extended
• Botulinum toxin A injection to the plantar or dorsiflexor muscle groups within the 6 months before the study
• Orthopaedic surgery to the legs in the previous year
• Uncontrolled epilepsy with daily seizures

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: FES start; Start: 4 weeks 'adaptation phase' and 8 weeks 'FES phase'. Adaption phase: the stimulus (in Volt) will gradually be increased up to an effective level and the wear time has to be increased from 30 minutes to 6 hours a day. FES phase: the participants have to wear the FES device for minimal 6 hours a day during walking. Usual physiotherapy can be continued during the FES phase. Second: after the FES phase, this group will enter the 'wash-out' period of 6 weeks for fading of the therapeutic effects, in which they return to their conventional therapy. Afterwards, 12 weeks of conventional therapy (orthoses/shoes and usual physiotherapy) with measurements at start and end will follow.	Device: FES; Functional electrical stimulation of the ankle dorsiflexors during walking, using a (superficial) neurostimulator with tilt sensor.
Other: Conventional start; Start: wearing usual orthoses/shoes on a daily basis for the first 12 weeks of the study. Usual physiotherapy can be continued. Second: after 12 weeks this group will enter a 6 week watch out phase, and next be switched to FES treatment for 12 weeks, consisting of: 4 weeks 'adaptation phase' with gradual increase of the treatment and 8 weeks 'FES phase'.	Device: FES; Functional electrical stimulation of the ankle dorsiflexors during walking, using a (superficial) neurostimulator with tilt sensor.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in goal attainment scale (GAS)	Goal attainment scale: definition of an individual goal at start, followed by a 6- point numeric scale indicating to what extent the goal is (score 0 till +2) or is not (-3 indicating detoriation till -1) reached.	Setting of goal(s) at start, assessment at every end of a phase: week 12, 18 and 30.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in participation	as measured in the Cerebral Palsy Quality of Life Questionnaire (see reference).	assessment at start and every end of a phase: week 12, 18 and 30.
Change in walking distance	Measured by the 6 minute walking test and the functional mobility scale (3 items, 6-point rating scale).	assessment at start and every end of a phase: week 12, 18 and 30.
Change in physical activity	measured by activity monitor	assessment at start and end of a phase (except for the wash-out phase): week 12 and 30.
Change in frequency of falling	measured by a questionnaire	assessment at every end of a phase: week 12, 18 and 30.
Change in stability during walking	measured by variation of center of mass and margins of stability assessed during 3D gait analysis	assessment at start and every end of a phase: week 12, 18 and 30.
Change in ankle dorsiflexion angle	measured in degrees during gait analysis during 3D gait analysis	assessment at start and every end of a phase: week 12, 18 and 30.
Change in calf muscle activation	Assessed by spasticity measurement and electromyography (EMG) during 3D gait analysis	assessment at start and every end of a phase: week 12, 18 and 30.
Change in ankle plantarflexion strength during walking	Calculated by net push off moments during 3D gait analysis	assessment at start and every end of a phase: week 12, 18 and 30.
Change in ankle dorsiflexion and plantarflexion strength	measured in Newton by handheld dynamometer	assessment at start and every end of a phase: week 12, 18 and 30.
Change in feelings about donning and doffing	measured by a questionnaire	assessment at start and every end of a phase: week 12, 18 and 30.
Change in patient satisfaction	measured by a visual analogue scale with smileys (0 = unsatisfied, 6 = perfectly satisfied).	assessment at start and every end of a phase: week 12, 18 and 30.
The compliance and acceptability of FES	derived from delivered stimulations and hours of wear time in the log file	the FES devices measures this automatically during wearing; so this will happen during the 12 weeks of FES therapy
Type of brain lesion in relation to FES success	Derived from available brain imaging	Assessment and analysis of available imaging will be done after completion of the study by the patient, so after week 30, up to week 50 to collect a batch of finished patients. No imaging will be performed because of the study.
Cost-effectiveness of FES	compared to conventional therapy	analysis after study completion, week 30, using the EQ-5D-Y results.
Change in health	EQ-5D-Y Questionnaire, youth version	assessment at every end of a phase: week 12, 18 and 30.

Collaborators and Investigators

• Sponsor: Maastricht University Medical Center
• Investigators: Principal Investigator: R.J. Vermeulen, prof M.D., Maastricht University Medical Center

Publications and helpful links

General Publications

• Moll I, Vles JSH, Soudant DLHM, Witlox AMA, Staal HM, Speth LAWM, Janssen-Potten YJM, Coenen M, Koudijs SM, Vermeulen RJ. Functional electrical stimulation of the ankle dorsiflexors during walking in spastic cerebral palsy: a systematic review. Dev Med Child Neurol. 2017 Dec;59(12):1230-1236. doi: 10.1111/dmcn.13501. Epub 2017 Aug 17.
• Waters E, Davis E, Mackinnon A, Boyd R, Graham HK, Kai Lo S, Wolfe R, Stevenson R, Bjornson K, Blair E, Hoare P, Ravens-Sieberer U, Reddihough D. Psychometric properties of the quality of life questionnaire for children with CP. Dev Med Child Neurol. 2007 Jan;49(1):49-55. doi: 10.1017/s0012162207000126.x.
• Moll I, Marcellis RGJ, Coenen MLP, Fleuren SM, Willems PJB, Speth LAWM, Witlox MA, Meijer K, Vermeulen RJ. A randomized crossover study of functional electrical stimulation during walking in spastic cerebral palsy: the FES on participation (FESPa) trial. BMC Pediatr. 2022 Jan 13;22(1):37. doi: 10.1186/s12887-021-03037-9.

Helpful Links

• Pubmed link to the review

Study record dates

Study Major Dates

• Study Start (Actual): August 1, 2018
• Primary Completion (Actual): September 10, 2021
• Study Completion (Actual): September 30, 2021

Study Registration Dates

• First Submitted: November 20, 2017
• First Submitted That Met QC Criteria: February 19, 2018
• First Posted (Actual): February 22, 2018

Study Record Updates

• Last Update Posted (Actual): October 4, 2021
• Last Update Submitted That Met QC Criteria: October 1, 2021
• Last Verified: September 1, 2021

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Neurologic Manifestations; Brain Damage, Chronic; Musculoskeletal Diseases; Muscular Diseases; Neuromuscular Diseases; Mononeuropathies; Peripheral Nervous System Diseases; Neuromuscular Manifestations; Muscle Hypertonia; Cerebral Palsy; Muscle Spasticity; Peroneal Neuropathies
• Other Study ID Numbers: NL63250.068.17

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: With publishing our results, an additional data file will be available containing the original individual data (anonymized) in order to make meta-analysis possible.
• IPD Sharing Time Frame: In the years 2020 and 2021.
• IPD Sharing Access Criteria: not yet known.
• IPD Sharing Supporting Information Type: CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: Yes