Usefulness of Bridging External Fixation for Prevention a Collapse in the Case of Osteoid Osteoma in the Lunate

INTRODUCTION: We report a patient with osteoid osteoma that developed in the lunate. CASE REPORT: The patient was a healthy 28-year-old male who had the right wrist joint pain and osteosclerosis of the lunate was noted on plain radiography. Kienböck’s disease was considered at the first examination, but a nidus was observed on computed tomography, suggesting osteoid osteoma in the lunate. The resection of the bone lesion and bridging external fixation to prevent post-operative collapse of the lunate was performed. Histopathological diagnosis was also osteoid osteoma in the lunate. At 3 years after surgery, no recurrence of the lesion or progression of collapse of the lunate has occurred. CONCLUSION: As the development of osteoid osteoma in the lunate is a markedly rare pathology and there are many differential diseases, the time to diagnosis may be prolonged. Moreover, it may be useful to attach bridging external fixation to prevent a collapse of the lunate.