Eosinophilic granuloma or Histiocytosis X occurs anywhere in the body, but commonly in the skull. Very often, it involves multiple systems and organs of the body.

Fibrous Dysplasia commonly involves the skull, ribs and long bones and has a typical "ground glass" appearance on X-rays. It can cause pain if large, and needs curettage and bone grafting.

Chondroblastoma typically affects the epiphysis of the growing skeleton (the growing part), which makes treatment more complicated than most. Fortunately it is very rare.

Enchondroma is a cartilage tumor that occurs within the long bones of the limbs and fingers, Sometimes it occurs in multiple sites, and is called Ollier's disease.

Chondromyxoid Fibroma is a bening tumor that occurs in the shaft of the long bone. It frequently causes pain and swelling. Treatment is by curettage and bone grafting. Local recurrence after surgery can occur.

Osteoid Osteoma is a small painful lesion, typically causing pain at night relieved by Aspirin. It can occur anywhere in the body, but commonly in the long bones and the spine. Diagnosis is by its typical appearance of a small dense lesion on X-rays. CT scan may be needed to delineate the lesion. Treatment is usually excision.

Osteoblastoma is a small painful lesion, usually affecting the spine. Treatment is by excison and bone grafting.

Ewing's Sarcoma can occur anywhere in the body, and is very aggressive in its spread to the rest of the body. Treatment is by chemotherapy.

Osteosarcoma occurs typically around the knee. It usually causes pain, and may be associated with a pathological fracture. Treatment consists of chemotherapy and surgery. Recent advances have improved 5-year survival to 70%. Limb sparing operations are also increasingly successful with more potent chemical agents.

Leukemia can present as bone pain, although blood tests will confirm the diagnosis.