Background: Osteoid osteoma is small, painful benign tumor of bone that usualy occurs in the long bones of the lower extremities. Phalanx of finger are extremly rare involved. The pain increases from mild to severe with progression during the night. The male to female ratio is approximately three to one and peak incidence is in the second decade. Radiography is the imaging modality of the first choice. If further characterization is necessary computed tomography can be helpful in cases where conventional radiography are indistinct. If uncertainty remains, bone scanning may be helpful, but some lesions require biopsy. Case Report: We report a case of an osteoid osteoma of the 28th female patient of the middle phalanx of the left middle finger treated by resection, curettage, and autologous bone grafting. Previously we perform a X-ray an CT scan imaging. Radiologist suggests after X-ray and CT scan images the bone biopsy for definitively diagnosis. Laboratory tests were within normal ranges. Discussion: Osteoid osteoma is slow growing, benign tumor, incidentally discovered at an early age as a palpable bony nodule. It is usually smaller than 2 cm and described by an osteoid nidus in a highly loose, vascular connective tissue. The nidus may contain a variable amount of well-demarcated calcification. Normal bone and zone of sclerosis surround the nidus. CT scanning is recommended when the nidus is not visible on conventional radiographs Conclusion: Osteoid osteoma is a benign lesion. Diagnosis could be based on the case history and the non-aggressive X-ray behavior of the lesion and occasionaly CT scan. A definite diagnosis can be ended only after the en-bloc resection and pathohistological verification.
Key words: osteoid-osteoma, phalanx tumor