Fig. 7

Postoperative computed tomography (CT) (sacrum). One-month postoperative CT (a transversal soft tissue window; b transversal bone window; c sagittal soft tissue window; d sagittal bone window) -abscess became smaller, and bone defect lesions show no changes. Three-month post-operative CT (e transversal soft tissue window; f transversal bone window; g sagittal soft tissue window; h sagittal bone window): no abscess, bone defect lesions became smaller. Six-month post-operative CT (i transversal soft tissue window; j transversal bone window; k sagittal soft tissue window; l sagittal bone window): new bone on edge of bone defect lesions (red arrows) and no relapse