title: Surface-based chondroblastoma of the tibia: a unique presentation.
abstract: BACKGROUND
  Chondroblastoma is a benign tumor classically located within the epiphysis of the long bones. The tumor is believed to arise from immature cells of the epiphyseal plate. Purely metaphyseal or diaphyseal chondroblastoma is exceedingly uncommon, occurring in approximately 2% of chondroblastoma cases. In all of these non-epiphyseal-based cases, the tumor has been intramedullary.
  
  
  METHODS
  We describe the histologic and imaging features of the first detailed description of a surface-based chondroblastoma.
  
  
  RESULTS
  The tumor was located in the anteromedial midshaft of the tibia in a 47-year-old male.
  
  
  CONCLUSIONS
  We discuss the diagnostic considerations and possible etiology of chondroblastoma given this unusual location.
authors: Mallinckrodt Institute of Radiology, Washington University School of Medicine, 510 South Kingshighway Boulevard, Campus Box 8131, St. Louis, MO, 63110, USA, demertzisj@mir.wustl.edu.
authors: Jennifer L
authors: JL
authors: Demertzis
authors: Michael
authors: M
authors: Kyriakos
authors: Sarah
authors: S
authors: Connolly
authors: Douglas J
authors: DJ
authors: McDonald
mesh_terms: D001859:Bone Neoplasms / Q000175:diagnosis*; D002804:Chondroblastoma / Q000175:diagnosis*; D003937:Diagnosis, Differential; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D013977:Tibia / Q000000981:diagnostic imaging* / Q000473:pathology*; D014057:Tomography, X-Ray Computed / Q000379:methods