The Intervention Effect of Exercise on Lumbar Multifidus Muscle Injuries

This is a single-center, prospective interventional study. The main purpose is to use ultrasound radiomics to analyze changes in multifidus muscle ultrasound imaging features before and after rehabilitation therapy in patients with low back pain related to lumbar multifidus injury, and explore whether these imaging features can be used to evaluate treatment response. Eligible participants are aged 18-80 years with chronic non-specific low back pain lasting more than 3 months, NRS/VAS pain score ≥1, and abnormal baseline ultrasound findings of the lumbar multifidus muscle. All participants will receive a 12-week home-based rehabilitation program, including prone multifidus activation exercises and core stability training, 3-5 times per week, 20-30 minutes each session. The primary outcome measures are changes in multifidus muscle area, ultrasound imaging features and pain scores after training. Safety will be monitored throughout the study. Training will be adjusted or paused if participants have increased pain, new radiating leg symptoms, dizziness, chest tightness, palpitations, or other adverse conditions.

Inclusion Criteria: 1. Aged 18-80 years old, no restriction on gender. 2. Diagnosed with non-specific low back pain with disease duration ≥ 3 months. 3. Numerical Rating Scale (NRS) / Visual Analog Scale (VAS) pain score ≥ 1 point. 4. Clinically suspected lumbar multifidus muscle injury or dysfunction, with at least one abnormal finding of lumbar multifidus muscle on baseline ultrasound examination, including reduced resting thickness, left-right asymmetry, decreased cross-sectional area or increased echogenicity. 5. Able to understand the research content and voluntarily sign the informed consent form. 6. Able to cooperate to complete rehabilitation training and follow-up assessments. Exclusion Criteria: 1. Presence of specific causes of low back pain, such as lumbar infection, tumor, fracture, inflammatory spondyloarthropathy, etc. 2. Obvious nerve root compression symptoms, cauda equina syndrome or progressive neurological deficits. 3. Previous history of lumbar spine surgery. 4. Severe lumbar spondylolisthesis, severe spinal stenosis, severe osteoporosis or other conditions unsuitable for rehabilitation training. 5. Complicated with severe cardiopulmonary disease, malignant tumor, systemic infection or other diseases intolerant to training. 6. Pregnant or lactating women. 7. Received systematic lumbar back rehabilitation training, local block/injection therapy or other interventions that may affect outcome assessment within the past 4 weeks. 8. Combined with severe mental disorders, cognitive impairment or poor compliance, unable to cooperate with the study. 9. Patients with long-term use of hormones or analgesic medications. 10. Other conditions judged by the investigator to be inappropriate for enrollment.