Effect of Masticatory Electrical Stimulation on Dysphagia in Spastic Cerebral Palsy

This study was conducted to evaluate the effectiveness of masticatory muscles electrical stimulation on oromotor skills, feeding level progress and child growth in children with dyaphagia. Forty children diagnosed as spastic cerebral palsy, from both genders, age ranging from 2 to 5 years were enrolled in the current study. They were randomly allocated in to study group (A) received oromotor exercises and neuromuscular electrical stimulation on masseter and digastric muscles and control group (B) received same exercises but placebo electrical stimulation. The result showed significant improvement in all variables in both groups. However, the study group showed significant different in feeding level in compare with control group.

Study design:

A randomized controlled clinical trial was conducted after interviews were done with the parents or care givers of all children, before starting the study to demonstrate the aim, procedures and potential benefits of the study. Children' parents provided written informed consent before the study was conducted.

Participants:

Forty spastic CP children (26 girls and 14 boys), age ranging from 2 to 5 years, participated in this study. They were selected based on the following criteria; having at least score (level 4) according to functional oral intake scale (FOIS), and they had good head control. Children were excluded if they had; oral hypersensitivity, acute or chronic dental problems, released primitive reflexes as asymmetrical tonic neck reflex or Seizures.

Participants who met the eligible criteria were assigned randomly to either study or control group of equal numbers. Each child in both groups received an oro-motor exercises program as home routine 3 times daily before each meal. Children in the study group received 20-minutes of neuromuscular electrical stimulation (NMES) (multi current SND 64227) which consisted of two-channels electrotherapy system designed for neuromuscular rehabilitation. The NMES was applied with 60 Hz of 230 milliseconds twice weekly for 8 weeks. While participants in the control group received placebo NMES.

Procedures:

Assessment:

1. weight and height Weight and height of each child were measured pre and post treatment by using weight and height measuring scale.
2. Feeding level Dysphagia feeding level was assessed by using functional oral intake scale (FOIS) , taking into consideration that tube dependent children at levels from 1-3 were excluded from the study).
3. Assessment of oromotor skills by oromotor assessment scale (OMAS).

Treatment:

Home routine exercises The exercises were demonstrated to the parents to warrant the uniformity of the training program. They were instructed to conduct the exercises three times daily before each meal. This home routine included passive movement, active movement and sensory stimulation.

1. Passive movement exercises:

   Passive movement included massage and passive range of motion (ROM) exercises. A-Massage: for gums, cheeks, lips and tongue for ten repetitions.
   * Gum massage: upper and lower gum massage started from middle of the gum to the end in the right and left side using regular brush.
   * Lip massage: started from side to side, it was applied for the upper then the lower lips.
   * Cheek massage: Applied intra oral in a circular way.
   * Tongue massage: Applied in the lateral side of the tongue from backward to forward direction in the right and left side using regular tooth brush.

   B-Passive range of motion was done for jaw, tongue and lips for ten repetitions.
   * Jaw movement: cupping lower jaw and move it up and down.
   * Tongue movement: Moving tongue laterally (right and left) and upward directions were done by tongue depressor and fingers.
   * Movement for lip closure: pushing the lips passively against each other like a kissing position.
2. Active movements:

   Active movement included active ROM for jaw, cheeks and lips and stretching for lips.

   A-Active ROM
   * Active jaw ROM: Jaw closure against resistance through biting on tongue depressor and holding for 6 seconds with ten times repetition.
   * Active cheek ROM: Cheek compress by drinking from straws with different diameters.

   B- lip stretching; Stretching upper and lower lips sustain twenty seconds for three sets.
3. Sensory stimulation; Sensory stimulation was done through Lollipop exercise by stimulation of lip closure, cheek and tongue movement through moving the lollipop in different directions.

Neuromuscular electrical stimulation The NMES was applied by the neo-faradic stimulation (Two channels system. The electrodes were applied bilaterally. The first channel was applied over the neck between the hyoid and jaw, (approximately on the belly of the digastric muscle). The second channel was applied on the side of the face, (approximately on the masseter muscle). The intensity level was determined by visible muscle contractions without pain sensation. For children in the study group, the intensity level was from 7 mA to 15 mA, the time of rise and fall was equal (50% raise and 50% fall) and the time on and off was fixed as; 3,1s:3,1s. While those in the control group received placebo NMES without any signals reached to the muscles.

All children received the treatment sessions 20 minutes, twice/weekly for 2 months in addition to home routine exercises.

Statistics:

Paired and unpaired t-test were conducted for comparison of the mean and slandered deviation for the demographic characteristics, weight gain and height variables. Mann-Whitney U test was conducted for comparison of median values of FOIS between both groups. Wilcoxon Signed Ranks Test was conducted for comparison between pre and post treatment median values of FOIS in each group.

The level of significance for all statistical tests was set at p \< 0.05. All statistical measures were performed through the statistical package for social studies (SPSS) version 22 for windows.

Results:

General characteristics of participants:

The pretreatment comparison between both groups showed insignificant difference regarding the mean values of age, weight and height (p\<0.05).

Regarding weight gain and height there was insignificant difference between both groups before and after treatment (p\>0.05). While pre and post treatment within group comparison revealed significant difference in both groups (p\<0.05).

Regarding the feeding level (FOIS) comparison of values between both groups considering the feeding level showed a statistically significant difference in each group after treatment. While between both groups, there was insignificant difference before treatment (p\>0.05). After treatment, there was significant difference between the study and the control groups in FOIS (p\<0.05).

Regarding to oromotor skills There was insignificant difference between both groups before and after treatment (p\>0.05), While a significant different was in each group after treatment when comparing it with its pretreatment value was recorded (p\<0.05)

Eligibility Criteria:
Inclusion Criteria:

* Diagnosis of spastic cerebral palsy.
* age ranged from 2 to 5 years.
* They had score level 4 or more according to functional oral intake scale (FOIS)
* They had head control

Exclusion Criteria:

* oral hypersensitivity.
* any acute or chronic dental problems
* released primitive reflexes as asymmetrical tonic neck reflex.
* seizures
* genetic syndrome