Effects of Therapeutic Exercise With and Without Nerve Stimulation on Dysphonia in Post Thyroidectomy Patients

Overview

This clinical trial evaluates rehabilitation strategies for post-thyroidectomy dysphonia. Voice impairment is a frequent complication following thyroid surgery. It often occurs even without direct laryngeal nerve transection. Surgical trauma, tissue edema, and mechanical stretching of the laryngeal nerves or surrounding musculature can cause persistent voice changes. These changes significantly lower a patient's quality of life.This study compares two distinct interventions against standard care:Therapeutic Voice and Neck Exercise AloneTherapeutic Voice and Neck Exercise Combined with Transcutaneous Electrical Nerve Stimulation (TENS)The objective is to determine if adding non-invasive nerve stimulation to standard therapeutic exercises accelerates neuromuscular recovery, improves vocal fold mobility, and enhances overall voice quality more effectively than exercise alone. Background and Rationale Thyroidectomies are common surgical procedures worldwide. Dysphonia post-surgery stems from multiple factors. These include temporary or permanent recurrent laryngeal nerve (RLN) neuropraxia, external branch of the superior laryngeal nerve (EBSLN) injury, laryngotracheal fixation, and peri laryngeal scarring. Patients frequently report hoarseness, vocal fatigue, reduced pitch range, and breathiness. Standard management typically includes watchful waiting or traditional voice therapy. Therapeutic exercises aim to stretch scarred tissues, strengthen paretic intrinsic laryngeal muscles, and optimize respiratory support. Transcutaneous Electrical Nerve Stimulation (TENS) uses low-voltage electrical currents to stimulate peripheral nerves. TENS is hypothesized to reduce local pain, increase regional blood flow, decrease muscle tension, and facilitate neural regeneration when applied to the anterior neck. By combining these therapies, this trial investigates whether sensory and motor electrical stimulation acts synergistically with active physical and vocal exercises. The goal is to provide a superior, faster recovery pathway for patients suffering from post-operative voice disorders.

Background and Clinical Problem Thyroid surgery (thyroidectomy) is a very common operation, but it often causes voice problems (dysphonia). Up to 80% of patients experience a change in their voice right after surgery, and 10% to 15% suffer from long-term hoarseness or vocal fatigue. These problems happen because the nerves that control the voice box get stretched or bruised during the operation. Furthermore, healing creates thick scar tissue that restricts the normal movement of the larynx, and the anesthesia breathing tube irritates the vocal folds. Right now, there is no standard therapy plan to help these patients recover.2. How the Combined Treatment Works This study tests a new treatment plan that combines physical voice exercises with gentle electrical nerve stimulation (TENS):Voice and Neck Exercises: These include manual throat massage to break up stiff scar tissue, neck stretches to reduce muscle guarding, and straw-blowing tasks (SOVT exercises) that use air back-pressure to protect the vocal folds from straining. TENS Therapy: Sticky electrode pads are placed on the neck. High-frequency pulses block pain signals naturally, while low-frequency pulses create tiny muscle twitches. This movement pumps away post-surgery swelling, boosts fresh blood flow, and helps bruised nerves heal. Study Setup and Methods This is a 6-week, single-blind, randomized controlled trial tracking 90 adult patients. Participants are randomly split into three equal groups : Group A (Real TENS + Exercise): Receives 20 minutes of active electrical nerve stimulation followed by 30 minutes of voice and neck exercises. Group B (Fake TENS + Exercise): Receives the exact same exercises but uses a fake TENS machine that shuts off after 30 seconds to control for the placebo effect. 4. Tracking Progress (Measurements)Patients are tested before the study, at 3 weeks, at 6 weeks, and 3 months later using three main methods: Patient Survey (VHI-30): A form where patients rate how much their voice issues disrupt their daily life.Computer Voice Analysis: A program that measures audio recordings for pitch shaking (Jitter), volume stability (Shimmer), and air leakage (Noise-to-Harmonic Ratio).Breath and Quality Tests: Clinicians measure the maximum seconds a patient can hold a vowel sound (Maximum Phonation Time) and rate voice harshness using the GRBAS scale. Data Analysis PlanThe study uses a statistical formula called a Two-Way Repeated Measures ANOVA. This math compares the scores across the three groups over the four different timelines. The main goal is to see if Group A (Real TENS + Exercise) demonstrates a significantly faster and more complete vocal recovery than the other two groups.