This study is evaluating the safety of using bioactive glass-containing bone cement combined with ultrasound during surgery for patients with metastatic bone tumors. We aim to see if this treatment can be safely applied to stabilize the bone and reduce pain, without causing unexpected side effects. All participants will receive standard care plus the study treatment, and we will closely monitor them during and after the procedure to check for any safety concerns.

Inclusion Criteria:

• 1.Age between 18 and 80 years (inclusive), regardless of gender; 2. Patients with advanced cancer, presenting with intractable pain due to clinically, radiologically and pathologically confirmed pelvic metastases; 3. Osteolytic lesions primarily located in the periacetabular or non-periacetabular regions; 4. Expected survival of more than 1 year; 5. Voluntarily agree to participate in this clinical trial, and the subject and/or their legal guardian is willing and able to provide written informed consent; 6. Demonstrates good compliance, is willing to follow medical advice, and is able to attend all required follow-up visits as specified in the protocol.

Exclusion Criteria:

• 1. Relative surgical contraindications, such as pelvic discontinuity or fracture displacement > 5 mm; 2. Poor general health status with an estimated survival of less than 3 months; 3. Destruction of the inner iliac cortex associated with soft tissue masses affecting vital organs, nerves, or blood vessels; 4. Presence of active systemic infection; 5. Previous history of bone cement injection at the target lesion site; 6. Severe hepatic or renal dysfunction (Child-Pugh class C, eGFR < 30 mL/min); 7. Coagulopathy or bleeding diathesis; 8. Known hypersensitivity or allergy to bone cement components; 9. Poor adherence, unwilling or unable to comply with postoperative treatment and/or rehabilitation regimens; 10. Patients who are mentally incompetent or unable to understand the requirements of study participation; 11. Unable to attend follow-up visits at the study institution; 12. Participation in another clinical trial within 3 months prior to enrollment in this study; 13. Pregnant or breastfeeding women.