May Be Caused by

 Common

Avascular necrosis

Bone cyst

Bone infarct

Bone island

Brown tumor of hyperparathyroidism

Callus

Chondroid lesion

Chronic or healed osteomyelitis

Enchondroma

Eosinophilic granuloma

Fibrous cortical defect

Garré sclerosing osteomyelitis

Granuloma

Hyperostosis frontalis interna

Idiopathic sclerosis

Irradiation

Langerhans cell histiocytosis

Mycetoma

Nonossifying fibroma

Osteoblastic metastasis

Osteochondritis dissecans

Osteochondroma

Osteoid osteoma

Osteoma

Paget disease of bone

Stress fracture

Tropical ulcer

Tuberculosis

 Uncommon

Chondrosarcoma

Condensing osteitis of clavicle

Ewing sarcoma

Fibrous dysplasia

Leukemia

Lymphoma

Mastocytosis

Melorheostosis

Meningioma

Ossifying fibroma

Osteitis condensans ilii

Osteoblastoma

Osteosarcoma

Parosteal sarcoma

Plasma cell granuloma

Removal of an intramedullary rod

Sternocostoclavicular hyperostosis

Syphilis

Treated lytic bone metastasis

Yaws