特発性側弯症の青少年のためのフィードバックベースバランストレーニング

Participants in this arm receive 40 minutes of clinic-based, physiotherapist-supervised individualized conservative scoliosis exercises followed by 30 minutes of HUBER® 360-based feedback balance training in the clinic. Sessions are delivered three times per week for 4 weeks (12 sessions in total) by a physiotherapist on a one-to-one basis.

Participants complete 30-minute balance training sessions on the HUBER® 360 Evolution multi-axial neuromuscular training platform (LPG Systems, Valence, France). The platform delivers real-time visual biofeedback on weight distribution and applied force through force sensors in the handles and an integrated screen. The protocol focuses on stretching the posterior chain, opening and increasing the concavity, and reinforcing the convexity. Sessions are supervised by a physiotherapist on a one-to-one basis.

Participants perform 40-minute supervised exercise sessions tailored to each patient's curve pattern, apex location, and clinical findings. The program includes posture exercises, pelvic tilt, symmetric extension, scapular adduction with pectoral stretching, asymmetric lateral stretching, Cotrel exercise, flexibility and strengthening exercises, and active three-dimensional postural correction. All sessions are delivered one-to-one by a physiotherapist experienced in scoliosis rehabilitation.

Participants in this arm receive 40 minutes of clinic-based, physiotherapist-supervised individualized conservative scoliosis exercises three times per week for 4 weeks (12 clinic sessions in total). In addition, participants perform a 30-minute structured home-based balance exercise program three times per week for the same 4-week period. The home-based balance program is taught in detail by a physiotherapist prior to the intervention period and performed independently by the participant at home.

Participants perform 40-minute supervised exercise sessions tailored to each patient's curve pattern, apex location, and clinical findings. The program includes posture exercises, pelvic tilt, symmetric extension, scapular adduction with pectoral stretching, asymmetric lateral stretching, Cotrel exercise, flexibility and strengthening exercises, and active three-dimensional postural correction. All sessions are delivered one-to-one by a physiotherapist experienced in scoliosis rehabilitation.

Participants complete a 30-minute structured home-based balance exercise program three times per week for 4 weeks. The program is taught in detail by a physiotherapist prior to the intervention period and performed independently by the participant at home. It includes bilateral and unilateral stance exercises, balance tasks with eyes open and closed, exercises on different surfaces, and controlled weight-shifting tasks, organized according to a progressive difficulty principle. No device-based or real-time biofeedback is used.

The primary outcome is the change in the Stability Index measured by the TecnoBody ProKin PK252 stabilometric platform (TecnoBody S.r.l., Dalmine, Italy). The Stability Index reflects overall postural control during a multi-axial dynamic balance task on the TecnoBody platform, where lower values indicate better postural stability. This parameter is conceptually comparable to the Overall Stability Index (OSI) reported by the Biodex Balance System, which was used as the reference source for the a priori sample size calculation.

Mediolateral postural sway variability is assessed during quiet standing on the TecnoBody ProKin PK252 stabilometric platform. The standard deviation of the medio-lateral component of the CoP trajectory is computed in millimeters, with lower values indicating reduced lateral postural sway.

Visual contribution to postural balance is quantified using the Romberg area ratio, calculated as the ratio of the eyes-closed CoP sway area to the eyes-open CoP sway area, both measured by the TecnoBody ProKin PK252 stabilometric platform. Higher ratios indicate greater visual dependence for postural control.

Functional dynamic balance is assessed using the Limits of Stability (LOS) test on the TecnoBody ProKin PK252 stabilometric platform. Participants perform controlled weight shifts toward eight directional targets, and the test result is expressed as the percentage of successfully reached targets within a fixed time. Higher LOS values indicate greater dynamic balance capacity.

Postural asymmetry and three-dimensional spinal alignment are assessed using the DIERS Formetric 4D system (DIERS International GmbH, Wiesbaden, Germany), a validated, radiation-free rasterstereographic surface topography method that reconstructs the three-dimensional shape of the back from projected light patterns. Pre-specified parameters include scoliosis angle, coronal and sagittal trunk imbalance, pelvic obliquity, pelvic torsion, kyphotic and lordotic angles, vertebral surface rotation, and lateral deviation. For all parameters, values closer to zero indicate greater postural symmetry

Static balance will be assessed using the Unipodal Balance Test. The duration (in seconds) that the participant is able to maintain balance on the right and left leg separately will be recorded.

Health-related quality of life is assessed using the Scoliosis Research Society-22 Patient Questionnaire (SRS-22), a validated patient-reported outcome measure for adolescent idiopathic scoliosis. Four domains (function/activity, pain, self-image/appearance, mental health) and a total score derived from these four domains are analyzed. The original instrument's fifth domain (satisfaction with management) is excluded because it cannot be administered at baseline. Each item is rated on a 5-point Likert scale, and a mean score is calculated for each domain and as a total. Possible scores range from a minimum of 1 to a maximum of 5, with higher scores indicating better health-related quality of life.

Demographic data including age, sex, height, weight, and body mass index (BMI) will be collected to describe the study population and to explore potential correlations with balance outcomes.