From the Guidelines
Osteoid osteoma is a benign bone tumor characterized by a small growth called a nidus, which consists of osteoid tissue surrounded by dense bone, typically affecting young people and causing pain that worsens at night and is relieved by nonsteroidal anti-inflammatory drugs (NSAIDs). The diagnosis of osteoid osteoma is primarily based on clinical presentation and imaging findings, with CT scans being the optimal imaging modality, as they are extremely sensitive for detection and precise delineation of the nidus 1. Some key characteristics of osteoid osteoma include:
- A small (less than 2 cm) growth called a nidus
- Consists of osteoid tissue surrounded by dense bone
- Typically affects young people, especially males between 10-30 years of age
- Most distinctive symptom is pain that worsens at night and is dramatically relieved by NSAIDs
- Pain is caused by the tumor's production of prostaglandins
- Most commonly occur in the long bones, particularly the femur and tibia, but can develop in any bone
- Diagnosis typically involves X-rays showing a small lucent nidus surrounded by reactive bone sclerosis, with CT scans being the gold standard for confirmation 1. Treatment options include continued NSAID therapy for pain management, as some tumors may resolve spontaneously over years, or definitive treatment through minimally invasive procedures like radiofrequency ablation or surgical removal, with most patients experiencing complete pain relief following appropriate treatment. The use of CT without and with IV contrast is preferred because it allows differentiation of areas of contrast enhancement from areas of osseous matrix production, and CT perfusion can facilitate further characterization in the setting of suspected osteoid osteoma, showing that enhancement curve morphology of the osteoid osteomas was significantly different from its mimickers 1.
From the Research
Definition and Characteristics of Osteoid Osteoma
- Osteoid osteoma is a benign bone tumor, typically found in the cortex of long bones 2.
- It consists of a radiolucent nidus surrounded by reactive osteosclerosis 2.
- The tumor usually affects young males, with a male to female ratio of 3:1 3.
- Osteoid osteomas account for roughly 10% of all benign bone tumors 3.
Clinical Presentation
- The typical clinical presentation of osteoid osteoma is nocturnal pain that eases with salicylates or nonsteroidal anti-inflammatory drugs (NSAID) 2.
- Patients often experience dull aching pain, worse at night, which can be relieved with NSAIDS 3.
- The pain can be resistant to analgesic or anti-inflammatory medication 4.
Diagnosis and Treatment
- Plain radiography and computed tomography are usually sufficient for the diagnosis of osteoid osteoma 2.
- Initial treatment includes salicylates and NSAID, as the tumor often regresses spontaneously over 2-6 years 2.
- Surgical treatment is indicated in case of unresponsive pain to medical therapy, no tolerance of prolonged NSAID therapy due to side effects, and no willingness to activity limitations 2.
- Minimally invasive techniques, such as CT-guided percutaneous radiofrequency thermoablation, have replaced open surgery and are considered the gold standard of surgical treatment 5, 2.
- Administration of nonsteroidal anti-inflammatory drugs can accelerate spontaneous healing of osteoid osteoma 6.