Abstract
Osteoma is a slowly growing, asymptomatic, benign osteogenic tumor. An extremely rare case of clavicular parosteal osteoma (PO) is reported. A 46-year-old female patient was treated with marginal resection after an open biopsy for a large, firm symptomatic mass originating from the middle part of the left clavicle, which recurred 25 years after surgery. In the fifth year postoperatively, the patient was followed up with a full range of motion of the left shoulder without any problem in her daily life. In this case report, the clinical course, imaging findings, diagnosis, and long-term results of a rare case of parosteal osteoma recurrence of the clavicle are described for the first time in the literature.