The aim of this study is to evaluate the short, medium and long-term efficacy and safety of vertebral body tethering, based on the results obtained at 3-5 months of follow-up, exploring not only the ability to correct scoliosis, but also the safety and ability to preserve the natural motility of the spine. To this end, the geometric and kinematic parameters of the spine through gait analysis, both during the execution of motor tasks such as walking at a flat level, and in static, upright posture and during the execution of elementary trunk movements will be analyzed, comparing patients undergoing vertebral body tethering and posterior spinal fusion.