Tissue fragments show medullary bone replaced by dense fibrous tissue and a marked chronic inflammatory infiltrate of mature lymphocytes, plasma cells and few neutrophils. The stroma contains coarse, dark brown-to-black granular pigment predominantly engulfed by sheets and clusters of histiocytes. No cytologic atypia or malignancy.
The patient had a non-union of the right femur with a broken intramedullary nail (IMN).
The surgeon removed the distal part of the broken IMN and extracted tissue for a biopsy and histopathology.
One soft tissue fragment measured 1x0.8x0.7 cm, totally embedded.
Femur non union fracture, biopsy: