Osteoid osteoma is the primary benign bone tumor derived from osteoblasts. It represents approximately 10 to 12% of primary benign bone tumors.
In the area of the foot it is relatively rare, most often occurring in the neck of the talus. Osteoid osteoma is characterized by a small size (usually lesser than 1.5 cm).
The tumor consists of the central nidus (hyper-vascularised tissue), which is surrounded by dense cortical bone zone. Typical is the occurrence in men under 25 years of age, the most common symptom is night pain that is relieved after aspirin (or other NSAID).
Other symptoms (oedema, ankle congestion) can mimic arthritis of the ankle. For diagnostics, CT or MRI can be used.
Open and arthroscopic resection or CT-guided radio-frequency ablation are included in treatment. Complete resection or destruction of the nidus, is coupled with very low recurrence rate and excellent prognosis. 52-year-old patient with left-sided periosteal osteoid osteoma of the neck of the talus is described in this case report.