The purpose of this study is to evaluate the acute effects of the self-elongation movement on the balance of patients (aged 8-16 years) suffering from adolescent idiopathic scoliosis,

Recruitment will be carried out by the physician during the scheduled follow-up. The participant and both parents, or the legal guardian, will receive information on the purpose and methods of this study. The informed consent of both parents, or the legal guardian, and of the minor will be requested.

Balance data (oscillations, sway area) will be collected by letting participants get on a stabilometric platform and placing their feet on the landmarks; position will not change for the duration of the assessments.

At the same time, the modification of the amplitude of the scoliotic curves will be evaluated with the use of the Spine 3D (medical class system) which uses micro-pulse laser technology to make a three-dimensional reconstruction of the spine.

Three 10-seconds assessments will be made. In the first the subject will reproduce the position hold for the scheduled radiography and an acquisition will be performed with the Spine3D. The obtained image will be compared with the radiographic one to improve the accuracy of the next evaluations. During the last two acquisitions, the stabilometric platform and the 3D Spine will be used simultaneously and the data for the study will be collected. The second acquisition will be performed in a physiological position and the third in self-lengthening, a position used in most of the rehabilitation methods for scoliosis. The full evaluation will take approximately 15 minutes.

Inclusion Criteria:

• diagnosis of idiopathic scoliosis, carried out by the Physician with the Adams test and the scoliometer;
• age between 8 and 16 years, both sexes;
• ability to perform the self-elongation movement;
• amplitude of the major scoliotic curve <40 degrees Cobb;
• scheduled annual follow-up which requires a radiograph.

Exclusion Criteria:

• secondary scoliosis;
• obesity;
• orthopedic pathologies that modify the plantar supports;
• pathologies that modify balance (neurological and / or vestibular);
• inability to understand and sign informed consent / assent.

Patients, of both sexes, affected by idiopathic scoliosis recruited at the Pediatric Orthopedics Outpatient Department of the University Hospital "Istituto di Cura Città di Pavia".

IPD sharing will take place upon direct request and after having defined a method that fully respects the privacy of the participants