Conclusion: The increase of oxidative stress, in PD patients' might be an additional reason for many secondary complications. Objective: Primary Aneurysmal Bone Cyst (ABC) is a histologically complex and mainly cystic lesion that accounts for 2 % of all primary bone tumors. Information regarding its clinical presentation and management in hands and feet remains sparse. Method: The medical records ABC in hands or feet in Hospital La Paz Pathology Department from 1966 to 2011 were retrospectively reviewed and compared with existing data. We also propose pathological criteria for differential diagnosis between ABC and giant cell reparative granuloma (GCRG).