I. Definition of Adolescent Idiopathic Scoliosis (AIS)

Adolescent Idiopathic Scoliosis (AIS) is a spinal deformity characterized by an abnormal lateral curvature of the spine, typically diagnosed during adolescence. The term "idiopathic" denotes that the cause of the condition is unknown, and it manifests without any underlying congenital or neuromuscular abnormalities. AIS is the most common type of scoliosis, accounting for approximately 80% of all scoliosis cases.