Research background Scoliosis is a common three-dimensional spinal deformity, especially in adolescents. In severe cases, it can lead to thoracic deformation and cardiopulmonary dysfunction. At present, clinical treatment is mainly based on Cobb angle to take observation, brace or surgical intervention, but there are problems such as poor compliance and large trauma. As a non-invasive massage therapy, leverage positioning manipulation has shown orthopedic effects in clinical practice, but its biomechanical mechanism has not been systematically quantified, which restricts its standardization and promotion.

Purpose of the study The purpose of this study is to quantify the mechanical and kinematic parameters of lever positioning manipulation in the treatment of scoliosis through biomechanical testing and finite element simulation technology, to construct an individualized finite element model, to analyze the stress and strain distribution of each structure of the spine under the intervention of manipulation, to reveal its biomechanical mechanism, and to provide scientific basis for the standardization of manipulation and the optimization of curative effect.

Research contents and methods The study is divided into two parts : In the first part, 30 patients with scoliosis were recruited. Through the integrated mechanical sensor and motion capture system, the mechanical parameters ( such as preload force, maximum pull force ) and kinematic parameters ( such as angle, angular velocity ) during the manipulation were recorded in real time. In the second part, based on the CT data of patients, the three-dimensional finite element model of T10-L2 segment was constructed by using Mimics, Geomagic, SolidWorks and ANSYS software to simulate the loading process of manipulation and analyze the stress and strain response of vertebral body, intervertebral disc and ligament complex under the action of manipulation.

Expected results and significance This study will systematically quantify the biomechanical characteristics of lever positioning manipulation for the first time, and clarify its mechanism of action in the treatment of thoracolumbar scoliosis. Through the finite element simulation, the stress distribution is visualized, which provides data support for the precision and individualization of manipulation, promotes the transformation of massage manipulation from ' experience dependence ' to ' quantitative science ', and lays a theoretical foundation for the development of intelligent orthopedic equipment in the future.

Ethics and quality control The study has passed the ethical review, and all participants will sign the informed consent. The manipulation was performed by the same experienced physician, and the data collection and analysis process was strictly controlled to ensure that the results were true and reliable.

Inclusion Criteria:

1. Age between 10 and 45 years, stable vital signs, no severe diseases in other systems;
2. Diagnosed with scoliosis via standard anterior-posterior and lateral spinal radiographs, with a Cobb angle of 10° < θ <= 45°, and no severe complications;
3. No history of spinal surgery;
4. Voluntarily willing to participate in this study as a subject to undergo LPM procedures, and signing the informed consent form by themselves or their guardian. Note: Only patients meeting all of the above four criteria can be included in this study.

Exclusion Criteria:

1. Individuals with severe osteoporosis, spinal fractures, tumors, infections, or lesions within the spinal canal;
2. Those with related complications, such as cardiopulmonary insufficiency (NYHA class >= II) or severe neurological disorders;
3. Those with compression fractures or spinal cord injuries;
4. Individuals with cognitive impairment or mental disorders who cannot cooperate with biomechanical testing;
5. Those with a history of spinal surgery;
6. Those with severe skin lesions or dermatological diseases at the operation site;
7. Women who are menstruating, pregnant, planning pregnancy, or in the postpartum period;
8. Those with other conditions that may reduce the likelihood of completing the procedure, such as a fear of manual therapy;
9. Individuals with unclear surface markers, affecting motion capture accuracy (e.g., BMI >= 35 kg/m^2).