It is probably a format Hamartoma or cartilage cells, which develops within a long bone. Grows slowly and rarely undergoes sarcomatous transformation. Expands in the host bone, sometimes obvious deformities resulting from the outside. It is generally observed in juvenile or adult age although his development dates probably from the earliest years of life, without sex predilection. Is located in the bones of origin cartilage, and with great preference for the long bones of the hands and feet; We can also be found in other long bones and rarely in the basin and in the vertebrae. Rarely reach the surface of the bone, producing a look "in the bowl".
The symptoms, because of slow growth of the tumor, generally starts with evidence of a swelling. Can become sore due to thin cortical bone fracture that around him, as often occurs in particular in the bones of the hands and feet.