Adolescent idiopathic scoliosis (AIS) leads to three-dimensional spinal deformity during adolescence, causing deviations in the frontal, sagittal, and axial planes, impairing physical function, balance, and lumbopelvic rhythm. Individuals with AIS exhibit decreased trunk movement, muscle overactivation, increased energy expenditure, balance/gait disturbances, and abnormalities in proprioceptive/vestibular input; pressure center deviations increase in postural control. These changes negatively impact daily life, pain, and quality of life.

Although the literature has examined the relationships between AIS and muscle activation, range of motion, pelvic position, and gait/balance, the relationship between lumbopelvic rhythm changes and curve type/localization/severity, and its impact on postural control and quality of life, has not been investigated. This study aims to elucidate movement patterns by evaluating lumbopelvic rhythm in individuals with AIS and to guide clinical diagnosis/treatment.

Adolescent idiopathic scoliosis (AIS) is a condition that emerges during adolescence and causes a three-dimensional deformity of the spine. This deformity can cause deviations in frontal, sagittal, and axial flight, negatively impacting physical function and balance control mechanisms. Lumbopelvic rhythm ensures the coordination of spinal and pelvic movements and is a critical factor for postural stability. Scoliosis can disrupt lumbopelvic rhythm by affecting pelvic and lumbar region movements. Individuals with AIS have been observed to exhibit changes such as decreased trunk flexion-extension movements and pelvic and hip movements during gait, overactivity of muscles involved in the spine and pelvis, increased energy expenditure, and changes in balance and limb alignment. Abnormalities in vestibular and proprioceptive input have also been observed, leading to changes in balance control. Postural control requires the integration of sensory and motor systems to maintain body balance. In individuals with scoliosis, changes in postural control can reduce mobility. Assessments of postural control, when compared to healthy individuals, have shown that those with scoliosis exhibit higher deviations and acceleration rates in pressure points. This can lead to difficulties in daily living activities, increased pain levels, and decreased quality of life. While the literature examines muscle activation, spinal range of motion, pelvic position, gait, and balance in individuals with AIS, studies on the distribution of lumbopelvic rhythm and its relationship to curvature type, localization, and work, as well as the impact of lumbopelvic rhythm on postural control and quality of life, have not been found. Therefore, evaluating lumbopelvic rhythm in individuals with AIS can contribute to a comprehensive understanding of changes in scoliosis-related movement patterns, guiding clinical diagnosis and treatment.

Inclusion Criteria:

• Inclusion criteria for the AIS group:
• Individuals diagnosed with AIS,
• Aged between 10-18 years,
• Having a Cobb angle greater than 10°,
• Having a pain intensity < 3,
• Volunteer individuals.

Exclusion Criteria:

• Male gender,
• Body mass index ≥30,
• Presence of additional pathologies affecting the lumbopelvic region (disc herniation, spondylolisthesis, hip dysplasia, rheumatic diseases, etc.),
• Chronic pain lasting longer than 3 months,
• Lower extremity length discrepancy > 2 cm,
• Orthopedic or neurological problems affecting the lower or upper extremity,
• History of acute injury,
• History of spinal surgery,
• Individuals with vestibular pathology or severe balance disorders.

Only individuals who identify as female are eligible to participate in this study.

The study group will consist of individuals diagnosed with AIS who apply to the Faculty of Physical Therapy and Rehabilitation at Hacettepe University. Participants in the healthy group will be selected using a snowball method from among the relatives of patients who apply to the Faculty of Physical Therapy and Rehabilitation or from among the relatives of the researchers.