Sections reveal an extensive inflammatory process within both soft tissue and bone. The soft tissue demonstrates florid granulation tissue, dense reactive fibrosis, hemorrhage, and vascular congestion, accompanied by a prominent mixed acute and chronic inflammatory infiltrate (lymphocytes, plasma cells, histiocytes, and scattered neutrophils). Multinucleated giant cells and osteoclasts are present as a secondary reactive process. The bone fragment shows reactive woven bone rimmed by active osteoblasts within a fibrotic, inflamed marrow space. Focal areas of devitalized bone (sequestrum) with empty osteocytic lacunae and surrounding inflammatory exudate are noted. No evidence of specific granulomas. There is no evidence of malignancy.
Left septic knee and chronic osteomyelitis of the left femur.
Soft tissue pieces measuring 6 x 5 x 1.2 cm in aggregate. Additionally, there is one separate bone fragment measuring 2 x 1.5 cm. All were totally embedded.
Left knee / Left femur lesion, debridement: