We aimed in this study:

1. To compare the ultrasonographic measurements of the abdominal muscles thickness symmetry in patients with adolescent idiopathic scoliosis (AIS) and adolescent healthy individuals
2. To investigate the effect of measured thickness and symmetry on pulmonary function test.

This cross-sectional,case-control clinical study included 40 patients diagnosed with AIS and 40 age and gender -matched healthy individuals. AIS group was evaluated for localization of curvature and degree of curvature. Ultrasonographic measurements and were performed of bilaterally abdominal muscle thickness in both groups. Spirometry evaluation was performed in both groups. Intragroup and intergroup data were compared.

Inclusion Criteria:

• Cobb angle over 10 degrees in radiological evaluation
• Between the ages of 10-18 and diagnosed with AIS by a specialist physiatrist

Exclusion Criteria:

• History of previous spinal surgery
• Patients using brace
• Those with any diagnosis of scoliosis other than AIS
• Those with a history of neuromuscular disease
• Previous spinal surgery
• Patients with neurological deficits on examination
• Patients with acute or chronic lung pathology
• Patients with abdominal surgery or injury
• Double curve or multiple curve
• Patients with concomitant chronic diseases
• The child's legal guardian does not allow it to take the tests

The control group:

• 10-18 volunteer adolescents without any health problems,
• In clinical evaluation: Healthy adolescents (without any asymmetric findings on three-way inspection, Adam's forward bend test and scoliometer) were included.

10-18 years old patient with AIS diagnosis 10-18 years old healthy adolescent volunteer