[Osteoid osteoma].

Osteoid osteoma is the third most common benign bone tumor. It usually affects the diaphysis of long bones, especially the femur or the tibia. This paper presents the case of a 22-year-old male patient, with pain in the left knee. The x-ray and ultrasound of the knee were normal. The three phase bone scintigraphy revealed a focal uptake in the mid shaft of the left femur, strongly suggestive of osteoid osteoma. This case shows the significant role of bone scintigraphy in the diagnosis of an osteoma osteoid with atipical presentation.