Pathological Fracture of Humerus with Implant Failure in Multiple Myeloma Patient: A Rare Case Report

摘要

A 42-year-old male diagnosed with multiple myeloma had a history of traumatic oblique fracture mid-shaft of right humerus managed by open reduction and internal fixation with plating at another center. After uneventful period of 1 year, he presented with pain and restricted movement of right shoulder and arm for 4 months. Radiograph exhibits osteolytic lesion (moth-eaten) underneath the plate and pathological fracture of mid-shaft humerus with implant failure. After excluding surgical contraindications, wide excision of tumor and reconstruction with tumor prosthesis was done using deltopectoral approach. Proximal humerus (15 cm) was excised along with the tumor mass and plate, leaving 5 cm of the distal humerus. Components of tumor prosthesis wrapped with prolene mesh were inserted using antibiotic cement. Capsule, rotator cuff tendons was sutured around the prosthesis head using nonabsorbable sutures. Postoperatively, the patient was managed in shoulder immobilizer for 3 weeks, assisted mobilization for the next 3 weeks and active mobilization at 6 weeks. The patient responded to chemotherapy postoperatively. At 1-year follow-up, the patient was able to perform activities of daily, achieved shoulder flexion (0°-90°), abduction (0°-50°) with no evidence of recurrence. Development of tumor metastasis with extensive humeral involvement in traumatic fracture of mid-shaft humerus treated with rigid fixation with a plate is a rare entity.