en جراحی زانو Knee surgery Abstract: Locally destructive aneurysmal bone cysts are bloodfilled reactive lesions of bone and in spite of destructive nature, are not considered to be true neoplasms. The accepted treatment for this lesion is curettage and bone grafting. Endoscopic curettage without bone grafting has been reported recently in treatment of aneurysmal bone cysts without aneurysmal dilatation and for small lesions. We present good results with endoscopic curettage without bone grafting in two patients with large and expanded aneurysmal bone cysts of the proximal humerus. Aneurysmal bone cyst,Endoscopy,Treatment 0 0 http://jros.iums.ac.ir/browse.php?a_code=A-10-39-29&slc_lang=en&sid=1 Khodamorad Jamshidi 1003194753284600605 1003194753284600605 No Shafa Orthopedic Hospital, Iran University of Medical Sciences, Tehran, IR Iran Mahmood Jabalameli 1003194753284600606 1003194753284600606 No Shafa Orthopedic Hospital, Iran University of Medical Sciences, Tehran, IR Iran Davod Jafari 1003194753284600607 1003194753284600607 No Shafa Orthopedic Hospital, Iran University of Medical Sciences, Tehran, IR Iran Farid Najd Mazhar najdmazhar.f@iums.ac.ir 1003194753284600608 1003194753284600608 No Shafa Orthopedic Hospital, Iran University of Medical Sciences, Tehran, IR Iran Hazhir Gharati 1003194753284600609 1003194753284600609 No Shafa Orthopedic Hospital, Iran University of Medical Sciences, Tehran, IR Iran