title: Quantitative analysis of the plain radiographic appearance of aneurysmal bone cysts.
abstract: OBJECTIVE
  To quantitate radiographic features that distinguish the plain radiographic appearance of aneurysmal bone cyst (ABC) from other solitary lesions of bone.
  
  
  METHODS
  Seven hundred nine cases of focal bone lesions, including 32 ABCs were analyzed according to demographic, anatomic, and plain radiographic features. Vector analysis of groups of features was performed to determine those that are most sensitive and specific for the appearance of ABC in contrast with other lesions in the data base.
  
  
  RESULTS
  Aneurysmal bone cysts most consistently are medullary-based, either eccentric or centric (94%), show lysis (100%), cortical thinning (97%), enlargement of the host bone (100%), and geographic bone destruction (94%). They have well-defined edges (84%), no fallen fragment (100%), no evidence of periosteal reaction (75%), and no visible matrix (91%). Although they typically occur in the metadiaphysis of long bones, the anatomic location and demographic data did not significantly affect the sensitivity or specificity for detection of ABCs. The vector analysis-generated differential diagnoses include giant cell tumor, unicameral bone cyst, nonossifying fibroma, enchondroma, and fibrous dysplasia as the major lesions.
authors.affiliation: Mallinckrodt Institute of Radiology, Jewish Hospital, Musculoskeletal Section, St. Louis, Missouri 63110, USA.
authors.forename: J A
authors.initials: JA
authors.lastname: Freeby
authors.forename: W R
authors.initials: WR
authors.lastname: Reinus
authors.forename: A J
authors.initials: AJ
authors.lastname: Wilson
mesh_terms: D000293:Adolescent; D000328:Adult; D001845:Bone Cysts / Q000000981:diagnostic imaging; D017824:Bone Cysts, Aneurysmal / Q000000981:diagnostic imaging* / Q000473:pathology; D001848:Bone Diseases, Developmental / Q000000981:diagnostic imaging; D001853:Bone Marrow / Q000000981:diagnostic imaging / Q000473:pathology; D001857:Bone Matrix / Q000000981:diagnostic imaging / Q000473:pathology; D001859:Bone Neoplasms / Q000000981:diagnostic imaging; D002648:Child; D002675:Child, Preschool; D002812:Chondroma / Q000000981:diagnostic imaging; D003937:Diagnosis, Differential; D005260:Female; D005357:Fibrous Dysplasia of Bone / Q000000981:diagnostic imaging; D005870:Giant Cell Tumors / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D010014:Osteolysis / Q000000981:diagnostic imaging / Q000473:pathology; D010521:Periosteum / Q000000981:diagnostic imaging / Q000473:pathology; D011859:Radiography / Q000706:statistics & numerical data; D012680:Sensitivity and Specificity