Osteoid osteoma is a benign bone tumor with typical clinical features of night pain, relieved by salicylates. It is common in adolescent and young boys. Intracortical location is the most common type with intraarticular and subperiosteal being other types. Intraarticular lesions demonstrate no surrounding sclerosis. 

MRI and CT are complementary in the diagnosis with MRI helping in identification of associated bone marrow edema.