title: Irregularity of the apophysis of the ischial tuberosity evaluated by magnetic resonance imaging.
abstract: OBJECTIVE
  To report the findings of magnetic resonance imaging (MRI) in two cases of apophyseal irregularity of the ischial tuberosity.
  
  
  METHODS
  The authors describe the MRI findings for two males who presented with pain of sudden onset in the buttock. Both patients were examined by radiography, MRI and computed tomography, and one underwent bone scanning.
  
  
  RESULTS
  On T1-weighted images, signal intensity was decreased in both the apophysis and the body adjacent to it; however, the signal intensity on T2-weighted images was increased. These findings are consistent with avulsion fracture of the apophysis.
  
  
  CONCLUSIONS
  The MRI findings in these cases may support the previously suggested hypothesis that apophyseal irregularity with characteristic radiographic changes over time is caused by avulsion fracture of the apophyseal line. The relation between the characteristic radiographic features and the structural changes associated with fracture in this condition is discussed.
authors.affiliation: Department of Orthopedic Surgery, Gunma University School of Medicine, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Watanabe
authors.forename: T
authors.initials: T
authors.lastname: Shinozaki
authors.forename: S
authors.initials: S
authors.lastname: Arita
authors.forename: M
authors.initials: M
authors.lastname: Chigira
mesh_terms: D000293:Adolescent; D002648:Child; D005500:Follow-Up Studies; D050723:Fractures, Bone / Q000175:diagnosis* / Q000000981:diagnostic imaging; D006801:Humans; D007512:Ischium; D008279:Magnetic Resonance Imaging; D008297:Male; D013177:Sports; D013997:Time Factors; D014057:Tomography, X-Ray Computed