Local Vibration for Drooling in Children With Cerebral Palsy

This randomized-controlled trial aims to evaluate the effects of local vibration therapy on drooling severity and perioral and submandibular muscle biomechanics in children with cerebral palsy. Participants will be allocated to either an experimental group receiving local vibration in addition to conventional physiotherapy or a control group receiving sham vibration with conventional physiotherapy. Local vibration will be applied to the perioral and submandibular regions for 5 minutes each over three consecutive days. Assessments will be conducted at baseline, immediately after the third intervention session, and at 1-week follow-up.

• Local Vibration Therapy (Other): Local vibration therapy will be applied to the perioral and submandibular regions using a vibration device for 5 minutes each (total 10 minutes per session), once daily for three consecutive days.
• Sham Vibration (Other): Sham vibration will be administered using the same device without contact with the skin. The intervention will be delivered for 10 minutes per session, once daily for three consecutive days.

Primary outcomes

• Muscle Tone [Baseline, immediately after the third intervention session, and 1-week follow-up]: Muscle tone of the perioral and submandibular muscles (orbicularis oris and anterior digastric muscles) will be evaluated using a portable hand-held myotonometer (MyotonPRO). The MyotonPRO applies a short mechanical impulse to the skin overlying the muscle or fascia. The tissue response generates a signal that is recorded, and the internal software produces an acceleration graph.
• Muscle Stiffness [Baseline, immediately after the third intervention session, and 1-week follow-up]: Muscle stiffness of the perioral and submandibular muscles (orbicularis oris and anterior digastric muscles) will be evaluated using a portable hand-held myotonometer (MyotonPRO). The MyotonPRO applies a short mechanical impulse to the skin overlying the muscle or fascia. The tissue response generates a signal that is recorded, and the internal software produces an acceleration graph.
• Muscle Elasticity (logarithmic decrement) [Baseline, immediately after the third intervention session, and 1-week follow-up]: Muscle elasticity of the perioral and submandibular muscles (orbicularis oris and anterior digastric muscles) will be evaluated using a portable hand-held myotonometer (MyotonPRO). The MyotonPRO applies a short mechanical impulse to the skin overlying the muscle or fascia. The tissue response generates a signal that is recorded, and the internal software produces an acceleration graph.

Secondary outcomes

• Change in drooling severity and frequency [Baseline, immediately after the third intervention session, and 1-week follow-up]: Drooling severity and frequency will be assessed using a standardized drooling scale, with severity scored from 1 (no drooling) to 5 (severe drooling) and frequency scored from 1 (no drooling) to 4 (constant drooling)
• Global Rating of Change Scale [Immediately after the third intervention session and 1-week follow-up]: Parent-reported global rating of change using the Global Rating of Change Scale. Scores range from -7 (very much worse) to +7 (very much improved), with higher scores indicating greater perceived improvement.
• Caregiver-reported drooling burden [Baseline, immediately after the third intervention session, and 1-week follow-up]: Caregivers will report the frequency of clothing changes and use of tissues related to drooling.

Sex: All, ages: 2 Years to 18 Years

Inclusion Criteria:

* Diagnosis of cerebral palsy
* Age between 2 and 18 years
* Presence of anterior drooling
* Drooling severity and frequency score ≥ 3 on a standardized drooling scale

Exclusion Criteria:

* History of surgical intervention for drooling management
* History of botulinum toxin injection for drooling management
* Use of medications affecting salivary control
* Presence of progressive neurological disease
* Presence of salivary gland pathology or active upper respiratory tract infection
* History or symptoms of aspiration pneumonia within the last 6 months
* Indication for surgical treatment of drooling (e.g., more than four clothing changes per day and presence of chin or neck dermatitis)
* Uncontrolled seizures
* Presence of oral or perioral lesions
* Presence of gastrostomy tube
* Treatment adherence below 85%

• Merve Tunçdemir, Asst. Prof., Principal investigator, Bitlis Eren University
• Ömer Dursun, Assoc. Prof., Principal investigator, Bitlis Eren University