Magnesium-Titanium Hybrid Intramedullary Nail System For Long Bone Fractures

Inclusion Criteria: 1. Aged ≥ 18 years and ≤ 80 years (inclusive), with skeletal maturity, regardless of gender; 2. Diagnosed with long bone fractures of the extremities (including femur, tibia, humerus) requiring surgical fixation with intramedullary nail; 3. Good treatment compliance, willing and able to complete follow-up and observation as required; 4. Voluntarily participate in this trial and sign the written informed consent form. Exclusion Criteria: 1. Pregnant or lactating women, or individuals with family planning during the study period; 2. Pathological fractures (e.g., bone tumor, bone metastasis, osteomalacia), or patients with too narrow or occluded medullary cavity; 3. Patients complicated with osteomyelitis, osteofascial compartment syndrome, systemic infection or local infection at the surgical site; 4. Patients with severe bone defects requiring artificial bone or autologous bone grafting; 5. Patients with severe soft tissue or vascular injury, or previous surgical treatment at the fracture site, where intramedullary nailing may not provide stable fixation; 6. Patients without sufficient soft tissue coverage at the proposed surgical site; 7. Patients diagnosed with severe osteoporosis by the investigator based on medical history and X-ray films of the fracture site; 8. Patients requiring simultaneous use of both intramedullary nail and screw-plate system at the planned surgical site; 9. Patients with hypermagnesemia (serum magnesium \> 1.25 mmol/L (3.0 mg/dL)); 10. Patients with uncontrolled diabetes mellitus (glycated hemoglobin HbA1c ≥ 8.0%); 11. Patients with severe cardiovascular, hepatic, renal, pulmonary, hematological diseases or metabolic disorders who cannot tolerate surgery; 12. Patients with previous or concurrent malignant tumors (excluding those cured and disease-free survival for more than 5 years, such as basal cell carcinoma of the skin, cervical carcinoma in situ, and papillary thyroid carcinoma); 13. Patients who have received radiotherapy, chemotherapy, growth factors, immunosuppressants, systemic corticosteroids, long-term (continuous use for more than 3 months) sedative-hypnotics, non-steroidal anti-inflammatory drugs, or bisphosphonates within 6 months prior to screening; 14. Patients with constitutions allergic to the implanted materials or known allergies; 15. Patients who have participated or are participating in any drug clinical trials within 3 months, or other medical device clinical trials within 30 days; 16. Other conditions where the investigator determines the patient is unsuitable for inclusion (e.g., metabolic bone disease, poliomyelitis sequelae, etc.).