Speech Motor Treatment in Cerebral Palsy

Cerebral palsy (CP) is the most frequent cause of motor disability worldwide, with a prevalence of 2-2.5 per 1000 live births. Children with CP may experience a variety of difficulties with communication including speech. Communication impairment has been identified in at least 40% of children with CP, with 36-90% of CP children experiencing motor speech impairment.

The aims of the current project are to test the effectiveness of intensive PROMPT treatment in a group of preschool children with CP and motor speech disorders (dysarthria/apraxia of speech) and to evaluate differences to the intervention response according to CP type, brain lesion severity and white matter integrity of corticospinal tract. We hypothesize that children with CP and motor speech disorders will benefit from 3 weeks of daily administration of PROMPT treatment and show measurable improvement of speech intelligibility on clinical and kinematic assessments, with 3 months stability. Outcome measures will include a standardized speech motor assessment as well as improvement in kinematic speech measures detected by a computerized system. We also hypothesize that children with dyskynetic CP will show more improvement induced by the PROMPT treatment as compared to children with spastic CP. We finally hypothesize that corticospinal microstructural integrity positively impact on intelligibility recovery, with children with better integrity having bigger improvements.

Our study of PROMPT with children with varying types of CP meets current international priorities of testing and implementing effective, earlier interventions, therefore investing in the improvement infant's health based on evidence, as a future investment for individuals and the community.

1. Rationale and purpose of research Cerebral palsy (CP) is the most frequent cause of motor disability worldwide, with a prevalence of 2-2.5 per 1000 live births. Several comorbidities characterize the clinical picture of children with CP, such as communication impairment, feeding difficulties, intellectual disability, vision and hearing impairment and epilepsy. Children with CP may experience a variety of difficulties with communication including speech, the development of gesture and facial expression, or receptive and expressive language, including voice production and intelligibility. Communication impairment has been identified in at least 40% of children with CP, with 36-90% of CP children experiencing motor speech impairment. Also, it has also been suggested that some children who do not present explicit dysarthria may have underlying speech motor control deficits. Intelligibility due to motor speech impairments affects activity and participation within various environments, reduces quality of life and increases daily care needs. Dysarthria may also be associated with excessive drooling and swallowing difficulties. Several studies consider compromised speech abilities as an indicator of the need for augmentative and alternative communication to supplement or replace communication. Conversely, CP and early acquired brain injury remain two of the most common medical causes of referral to speech and language therapy. However, little effort has been made in systematically improving speech motor abilities of children with CP by using early, reproducible and targeted intervention strategies. Furthermore, a poor relationship between the motor command and perceptual consequence of the speech movement has been hypothesized as a possible mechanism of speech dysfunction in CP, suggesting a potential therapeutic value of enhancing tactile-kinesthetic input to motor speech abilities of CP children.
2. Review of literature There are few papers reporting trials on targeted standardized intervention for speech motor deficit in infants or children with CP, with little evidences on treatment effectiveness. In a small group of children aged 3-11 years, it has been suggested that the effect of a speech motor treatment was aligned with the core principles of dynamic systems theory such as PROMPT (Prompts for Restructuring Oral Muscular Phonetic Targets) in changing speech motor patterns of children with CP with proven benefits in intelligibility, documented by kinematic analyses. Several types of CP were included (dyskinetic, spastic unilateral and bilateral). In a group of 7 children with spastic quadriplegia, some outcome of a motor speech treatment originally developed for adults with Parkinson disease were validated, the Lee Silverman Voice Treatment (LSVT LOUD). They also showed changes in white matter integrity supporting behavioral changes.
3. Research questions/Hypothesis Aim 1: To test the effectiveness of intensive PROMPT treatment in a group of preschool children with CP and motor speech disorders (dysarthria/apraxia of speech).

   Aim 2: To evaluate differences to the intervention response according to CP type, brain lesion severity and white matter integrity of corticospinal tract.

   Primary Hypothesis: children with CP and motor speech disorders will benefit from 3 weeks of daily administration of PROMPT treatment and show measurable improvement of speech intelligibility on clinical and kinematic assessments, with 3 months stability.

   Secondary hypotheses: children with dyskynetic CP will show more improvement induced by the PROMPT treatment as compared to children with spastic CP. Investigators also hypothesize that children with less severe brain lesions will have a higher level of improvement compared to children with more severe brain lesions. Investigators finally hypothesize that corticospinal microstructural integrity positively impact on intelligibility recovery, with children with better integrity having bigger improvements.
4. Method Investigators plan a randomized trial of PROMPT in children with CP using a wait-list control group. Eligible children will be randomized into either immediate treatment or wait-list-control groups. This design allows every child meeting inclusion criteria to eventually receive the treatment and avoids issues of equipoise. For CP wait-listed controls, the study continues for 3 weeks longer and results into an additional assessment.

Because PROMPT has been shown to be beneficial in several older children with CP, investigators' rational for the design allows for achievement of the RCT data collection and analysis, as well as allow all identified and consented children to receive the intervention.

The participants will include children between 3 and 9 years of age, with a diagnosis of CP and speech motor disorders. Parents will be asked to consent for the children for the participation in the study. All study activities will be carried out in our clinical center setting with a PROMPT trained therapist with appropriate knowledge of clinical research process.

In investigators' studies of rehabilitation with the CP population consent to participate in studies approaches 90%. From investigators' experience and clinical demographics of the center, they were expected 30 patients diagnosed CP with speech difficulties in the requisite age group per year, making possible a design of staggered enrollment of intervention and wait-list-control groups in the RCT. Recruitment will be completed according to the standards of research consent, followed by group randomization, by a team member other than the treating therapist. The assessments will be completed by an experiences SLP, different from the treating therapist.

Eligibility Criteria:
Inclusion Criteria:

* child between 2 and 9 years with a diagnosis of CP, with normal to mild intellectual disability and adequate language comprehension skills
* motor speech deficit

Exclusion Criteria:

* utilization of AAC strategies as the only means of communication,
* medical fragility or anatomical malformations affecting speech production preventing the ability to participate in the intervention