A rare case of aneurymal bone cyst of cuboid bone in a 10-year-old girl.

Aneurysmal bone cysts (ABC) are rare and they represent 1- 1.4 % of all primary bone tumors. ABC of cuboid bone are extremely rare, especially in children. Very few cases have been reported in the literature since 1967. We present a case of pathological fracture of cuboid bone due to an aneurysmal cyst in a 10-year-old girl. Surgery was performed, which included open biopsy with aspiration and intralesional curettage . Bone defect was then filled in by fully synthetic cancellous bone graft substitute consisting of pure β-tricalcium phosphate. Aneurysmal cyst of cuboid bone with pathological fracture could be successfully treated with pure β-tricalcium phosphate as a bone graft substitute. This procedure is safe with excellent outcome.Follow up to nearly four years did not show any recurrence.