Bone and Soft Tissue Tumors

Osteoid Osteoma

What is osteoid osteoma?

Osteoid osteoma is a benign bome tumour.  It is characterised with  a 1-1.5 cm in diameter nidus of fibrous and vascular tissue  surrounded by reactive bone formation. The incidence is 10% of all benign bone tumours. It is seen commonly between the ages of 5-20. The tumour is frequently observed in  proximal femur (the upper end of the thigh bone), the tibia (shin bone), the posterior elements of the spine and  humerus (arm bone).

What are the findings of osteoid osteoma?

The most common sign  is pain, experienced especially at night. The most important feature of this pain is being alleviated with the use of aspirin and other anti-inflammatory medicine. If the tumour is located in the epiphysis, joint pain, swelling may be seen additionally as a result of synovitis.

How is the diagnosis of osteoid osteoma made?

Clinical and radiological diagnosis is possible. The definitive diagnosis is made by pathological examination. A 1-1.5 cm radiolucent nidus and the surrounding extremely dense reactive bone tissue on plain radiographs is diagnostic. Sometimes nidus location can not be made directly on x-rays and Computed Tomography of the nidus is needed to determine the exact location.

What is the treatment?

The tumour does not  spread remotely to other parts of the body. Surgical removal of the nidus or percutaneous radiofrequency ablation therapy in suitable cases provides a complete cure. Post-operatively, pain is typically completely over. Patients are followed for the development of localized epiphyseal bone. No recurrence observed after treatment.

osteoid osteoma humerus

osteoid osteoma humerus radioraphy

osteoid osteoma computed tomography

osteoid osteoma CT


intra-cortical location of nidus


radio-frekans ablation

CT radio-frekans ablation techniques

About the author

Prof.Dr. Seref Aktas