Schroth and Scapular Muscle Activation in Hyperkyphosis

This prospective, randomized controlled trial aims to investigate the effects of Schroth-based three-dimensional exercises on scapular muscle activation in children with postural thoracic hyperkyphosis. Thoracic hyperkyphosis, commonly observed during childhood and adolescence, not only leads to spinal deformity but also negatively impacts scapular positioning, upper extremity function, and overall posture. Weakness and poor activation of scapular stabilizing muscles may contribute to the progression of kyphosis and functional limitations.

The Schroth method is a scoliosis-specific exercise approach designed to improve spinal alignment through three-dimensional postural correction, rotational breathing, and muscle stabilization techniques. Although widely used for spinal deformities such as scoliosis and kyphosis, its specific effects on scapular muscle activation remain insufficiently studied. This study will explore the potential of Schroth exercises to enhance scapular muscle function, which may contribute to improved posture, increased muscle strength and endurance, better scapular performance, reduced kyphotic appearance, and alleviation of pain.

The intervention group will participate in an 8-week supervised exercise program consisting of individualized Schroth exercises, focusing on postural awareness and scapular control during functional activities. By targeting scapular muscle activation, the study seeks to determine whether integrating Schroth exercises into physiotherapy practice can improve clinical outcomes and inform evidence-based approaches for managing postural thoracic hyperkyphosis in the pediatric population. Findings from this study may also contribute to developing preventive health strategies to protect musculoskeletal health in children and adolescents.

• Schroth (Other): The Schroth intervention consists of a structured, three-dimensional exercise program based on scoliosis-specific principles. It incorporates corrective postural alignment, rotational breathing techniques, and targeted activation of spinal and scapular stabilizing muscles. The exercises are designed to improve postural control, enhance muscle endurance, and promote neuromuscular re-education for better functional alignment during daily activities.

Primary outcomes

• Muscle Activation (sEMG) [8 weeks]: Surface electromyography (sEMG) will assess the activation of the upper, middle, lower trapezius, and serratus anterior muscles, following SENIAM protocols. Signals will be normalized to %MVC and analyzed for concentric, isometric, and eccentric phases using RMS methods with a 20 Hz high-pass filter.

Secondary outcomes

• Muscle Strength [8 weeks]: Scapular stabilizing muscle strength will be measured using a handheld dynamometer (Lafayette Instrument). Higher force values (in Newtons) indicate greater muscle strength and improved functional capacity of the scapular muscles. An increase in the score reflects muscle strength gains, while a decrease indicates weakness or functional decline.
• Scapular Muscle Endurance Test [8 weeks]: Scapular muscle endurance will be evaluated using the Scapular Muscle Endurance Test, which measures the duration (in seconds) that scapular muscles can sustain an isometric contraction. A higher score indicates better endurance capacity, while a lower score reflects fatigue or reduced muscle endurance.
• Kyphosis-Specific Spinal Appearance Questionnaire [8 weeks]: The Kyphosis-Specific Spinal Appearance Questionnaire is a 10-item, 5-point Likert scale (range: 1 to 5 per item, total score range: 10 to 50) designed to assess patients' perception of their spinal appearance related to thoracic hyperkyphosis. Higher scores indicate worse perceived deformity and greater concern about appearance.
• PostureScreen Mobile Application [8 weeks]: Provides objective measurements of postural deviations. Improvements are indicated by reductions in deviation angles or distances.
• Postural Habits and Awareness Scale [8 weeks]: The Postural Habits and Awareness Scale consists of 19 items, each scored on a 5-point Likert scale (total score range: 19 to 95). Higher scores indicate better postural habits and awareness.
• Numeric Rating Scale (NRS) [8 weeks]: Pain intensity will be measured using the Numeric Rating Scale (NRS) during rest, physical activity, and at night. The scale ranges from 0 (no pain) to 10 (worst possible pain). A decrease in NRS scores indicates pain relief, while an increase signifies worsening pain.
• Global Rating of Change (GROC) scale [8 weeks]: Participant satisfaction with the intervention will be assessed using the Global Rating of Change (GROC) scale. The GROC is an 7-point scale ranging from -3 (very much worse) to +3 (completely recovered), with 0 indicating no change. Positive scores indicate perceived improvement, zero represents no change, and negative scores indicate worsening of symptoms or dissatisfaction with the treatment.

Sex: All, ages: 7 Years to 18 Years

Inclusion Criteria:

* Thoracic kyphosis angle (Cobb) between ≥40° and <70° on lateral radiographs
* Aged 7-18 years
* Risser stage 0-5, indicating ongoing skeletal development

Exclusion Criteria:

* Congenital or rigid spinal deformities/anomalies
* Major musculoskeletal surgery or trauma, especially involving the spine
* Physiotherapeutic intervention for the spine in the last 6 months
* Current brace use
* BMI ≥ 30
* Regular upper extremity sports involvement (e.g., swimming, volleyball) at least twice a week for one year
* More than 60 minutes of moderate-to-high intensity physical activity per week
* Visual impairments or light sensitivity
* Positive vestibular (Unterberger) test
* Hearing impairments
* Cognitive difficulties affecting comprehension
* Systemic diseases (diabetes, hypothyroidism, infection, malignancy)
* Neurological disorders
* Active rheumatic diseases

• Ayşe Zengin Alpözgen, Assoc Prof., Principal investigator, Istanbul University - Cerrahpasa