title: Patterns of premature physeal arrest: MR imaging of 111 children.
abstract: OBJECTIVE
  The purpose of this study was to use MR imaging, especially fat-suppressed three-dimensional (3D) spoiled gradient-recalled echo sequences, to identify patterns of growth arrest after physeal insult in children.
  
  
  METHODS
  We evaluated 111 children with physeal bone bridges (median age, 11.4 years) using MR imaging to analyze bridge size, location in physis, signal intensity, growth recovery lines, avascular necrosis, and metaphyseal cartilage tongues. Fifty-eight patients underwent fat-suppressed 3D spoiled gradient-recalled echo imaging with physeal mapping. The cause, bone involved, radiographic appearance, and surgical interventions (60/111) were also correlated. Data were analyzed with the two-tailed Fisher's exact test.
  
  
  RESULTS
  Posttraumatic bridges, accounting for 70% (78/111) of patients, were most often distal, especially of the tibia (n = 43) and femur (n = 14), whereas those due to the other miscellaneous causes were more frequently proximal (p < 0.0001). The position of the bridge in the physis was related to the bone involved (p < 0.0001). Sixty-five percent of distal tibial bridges involved the anteromedial physis, whereas 60% of the distal femoral arrests were central. Larger bridges had higher T1 signal intensity (p < 0.008). Oblique growth recovery lines were seen exclusively with bridges involving the peripheral physis (p = 0.002) and smaller, more potentially resectable bridges. Metaphyseal cartilaginous tongues were seen with all causes, but avascular necrosis was exclusively posttraumatic (p = 0.03). Signal characteristics and bridge size did not vary with the cause.
  
  
  CONCLUSIONS
  Premature physeal bony bridging in children is most often posttraumatic and disproportionately involves the distal tibia and femur where bridges tend to develop at the sites of earliest physiologic closure, namely anteromedially and centrally, respectively. MR imaging, especially with the use of fat-suppressed 3D spoiled gradient-recalled echo imaging, exquisitely shows the growth disturbance and associated abnormalities that may follow physeal injury and guides surgical management.
authors.affiliation: Department of Radiology, Children's Hospital, Harvard Medical School, 300 Longwood Ave., Boston, MA 02115, USA.
authors.forename: Kirsten
authors.initials: K
authors.lastname: Ecklund
authors.forename: Diego
authors.initials: D
authors.lastname: Jaramillo
mesh_terms: D000293:Adolescent; D001133:Bones of Upper Extremity / Q000000981:diagnostic imaging / Q000254:growth & development / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D004838:Epiphyses / Q000000981:diagnostic imaging / Q000293:injuries / Q000473:pathology*; D005260:Female; D006130:Growth Disorders / Q000209:etiology / Q000473:pathology*; D006801:Humans; D007867:Leg Bones / Q000000981:diagnostic imaging / Q000254:growth & development / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D011859:Radiography; D012189:Retrospective Studies