This is chronic osteomyelitis. Note the fibrosis of the marrow space accompanied by chronic inflammatory cells. There ca这是一张慢性骨髓炎的切片，髓腔内有显著纤维化伴慢性炎性细胞浸润，还可见伴有骨重建的骨破损。骨髓炎是一种难治性疾病。