A Rare Bone Erosion due to Fibroma of the Tendon Sheath.

Introduction:Fibroma of the tendon sheath (FTS) is a soft-tissue tumor strongly attaches to the tendon sheath. The most common tumor which causes bone erosion is giant cell tumor of the tendon sheath while the erosion is quite rarely caused by FTS. Case Report:A 50-year-old housewife presented a swelling around the A1 pulley of the right third finger as well as bone erosion and a trigger finger. Against our preoperative suspect as GTTS, the pathological findings showed FTS. The snapping disappeared after the surgery. At 2.5 years postoperatively, we found no recurrence. Conclusion:FTS can be added to one of the differential diagnoses for tumor presenting bone erosion in fingers though our case is rare.