Osteoid Osteoma

Osteoid osteoma is a small, benign bone tumor that most commonly affects the long bones of the body, such as the femur and tibia. It primarily involves the skeletal system and causes localized bone pain that often worsens at night. This pain is typically relieved by nonsteroidal anti-inflammatory drugs (NSAIDs), which is a distinctive feature. The tumor is usually less than 2 cm in size and consists of a central core called a nidus surrounded by reactive bone. Although it is not cancerous, the pain and discomfort can significantly impact daily activities and quality of life. The condition most often occurs in children and young adults. Diagnosis and treatment focus on confirming the lesion and managing symptoms.

Osteoid osteoma is a benign osteoblastic bone tumor characterized by a small, well-demarcated nidus of osteoid and woven bone surrounded by reactive sclerotic bone. It arises due to abnormal proliferation of osteoblasts producing immature bone matrix. The lesion typically measures less than 2 cm and is most common in the cortex of long bones, especially the femur and tibia. The hallmark clinical feature is nocturnal bone pain that responds dramatically to NSAIDs due to high levels of prostaglandin production within the nidus. Radiographically, it presents as a radiolucent nidus with surrounding sclerosis. The tumor is significant because it causes intense pain disproportionate to its size and can mimic other bone pathologies. It primarily affects adolescents and young adults and rarely undergoes malignant transformation.