Surface Electromyographic Analysis of Scapular Stabilizer Muscle in Postural Hyperkyphosis

Postural hyperkyphosis is characterized by an excessive thoracic kyphotic curvature and may alter scapular positioning, muscular balance, and upper extremity biomechanics. Scapular stabilizer muscles play an important role in maintaining postural alignment and ensuring efficient force transmission throughout the kinetic chain. Exercise-based interventions, including conventional postural exercises and the Schroth method, are commonly used in the conservative management of postural hyperkyphosis. However, evidence directly comparing scapular stabilizer muscle activation during these exercise approaches remains limited. The Schroth method is a three-dimensional corrective exercise approach incorporating active spinal elongation, postural correction, rotational breathing, and isometric muscle activation, whereas conventional postural exercises primarily focus on muscle strengthening, stretching, spinal mobility, and postural alignment. The aim of this study is to compare the activation levels of scapular stabilizer muscles, including the serratus anterior, rhomboids, middle trapezius, and lower trapezius, during Schroth-based corrective exercises and conventional postural exercises in young adults with postural hyperkyphosis using surface electromyography. Isometric muscle strength of the same muscle groups will also be evaluated. The study will focus on immediate muscle activation patterns during exercise performance rather than long-term treatment outcomes. The findings are expected to provide objective evidence regarding muscle recruitment patterns during different corrective exercise approaches and contribute to the development of more individualized and targeted exercise programs for individuals with postural hyperkyphosis.

Inclusion Criteria: * Aged between 18 and 35 years. * Thoracic kyphosis angle between 45° and 60° on lateral radiographic assessment or a kyphosis index score of 13 or higher measured using the Flexicurve method. Exclusion Criteria: * Presence of congenital or rigid spinal deformities or structural abnormalities. * History of major musculoskeletal surgery or trauma, particularly involving the spine. * Receipt of physiotherapy interventions targeting the spinal region within the previous six months. * Body mass index (BMI) ≥ 30 kg/m². * Diagnosed hearing impairments. * Difficulty understanding or following verbal instructions. * Presence of systemic diseases, including diabetes mellitus, hypothyroidism, infections, or malignancies. * Presence of neurological disorders. * Presence of active rheumatic diseases.