Back pain is common and is a leading cause of disability and financial burden [1]. The prevalence and characteristics of low back pain (LBP) have been extensively researched in adults but are less elucidated in adolescents. Previous studies have shown that the point prevalence of back pain ranges from 12% to 33 % [[2], [3], [4], [5], [6]] and that the lifetime prevalence ranges from 28% to 51 % [2,4,[6], [7], [8], [9]]. Moreover, back pain significantly impacts disability by reducing physical activity, causing school absences, and limiting daily activities [[10], [11], [12]].

Adolescent idiopathic scoliosis (AIS) is a relatively common spinal condition in adolescents; its prevalence is approximately 1%–3% [13,14]. Since the evaluation methods and definitions of back pain and LBP differ among previous studies, the prevalence of back pain in patients with AIS varies from 28% to 68 %, which is higher than that in healthy adolescents [[15], [16], [17]]. Moreover, these studies had significant limitations, including a lack of comparative controls and detailed information about scoliotic deformity or pain location. Sato et al. reported that the AIS group showed higher point prevalence and lifetime prevalence of back pain, as well as significantly more back pain in the upper and middle right back compared with healthy controls; however, these data were based on a small sample of patients with mild scoliosis (n = 51) [15]. Moreover, relationships with curve type or scoliosis severity have not yet been clarified. Therefore, we conducted a large-scale, cross-sectional epidemiological survey to clarify the characteristics of back pain and the relationships between back pain and scoliosis curve types or curve severity in non-surgically treated patients with AIS, based on a questionnaire administered to all adolescents in the cohort.