Evaluation of the Safety and Efficacy of Artificial Bone Repair Materials for Repair of Long Bone Defects in the Extremities

Inclusion Criteria: 1. Age ≥ 18 years old and ≤ 60 years old, regardless of sex; 2. Cavitary bone defects in the limbs requiring bone grafting treatment; 3. Bone defect volume ≥ 1 cm³ and ≤ 8 cm³, with only one bone defect requiring intervention; 4. Subjects or their legal guardians can understand the study objectives, demonstrate sufficient compliance with the study protocol, and sign the informed consent form. Exclusion Criteria: 1. Open fractures with wound contamination; 2. Repair of infectious bone defects; 3. Structural bone grafting required at the defect site; 4. Osteofascial compartment syndrome in the affected limb scheduled for surgery; 5. Presence of systemic infection, uncontrolled local infection at the surgical site, malignant tumor (including metastatic tumors) at the defect site, osteonecrosis at the defect site, severe nerve/soft tissue/vascular injury at the defect site, confirmed severe malnutrition, or dysfunction/failure of other vital organs; 6. Calcium and phosphorus metabolic abnormalities (calcium/phosphorus levels \> 1.5 times the upper limit of normal values); 7. History of diabetes with fasting blood glucose ≥ 6.1 mmol/L; 8. Coagulation dysfunction (prothrombin time \[PT\] or activated partial thromboplastin time \[APTT\] \> 2 times the upper limit of normal values); 9. Use of chemotherapeutic agents or receipt of radiotherapy within 3 months prior to enrollment; 10. Cumulative use of corticosteroids or growth factors for ≥ 14 days within 1 month prior to enrollment; 11. Long-term use of sedative-hypnotic drugs (continuous use for \> 3 months) or non-steroidal anti-inflammatory drugs (NSAIDs, continuous use for \> 3 months); 12. Known allergy to bovine-derived materials or collagen products; 13. Pregnant or lactating females; 14. Participation in other interventional clinical trials for drugs or medical devices within 1 month prior to enrollment; 15. Any other conditions where investigators, in their professional judgment, deem the subject ineligible to participate in the trial for the subject's safety or benefit.