Epiphyseal lytic lesion

Chondroblastoma is a rare, benign, locally aggressive bone tumor that typically affects the epiphyses or apophyses of long bones. It is thought to arise from an outgrowth of immature cartilage cells (chondroblasts) from secondary ossification centers, originating from the epiphyseal plate or some remnant of it.Chondroblastoma is very uncommon, accounting for only 1-2% of all bone tumors. [Source: Wikipedia ]