title: Posterior periosteal disruption in Salter-Harris Type II fractures of the distal femur: evidence for a hyperextension mechanism.
abstract: OBJECTIVE
  Patterns of periosteal disruption are important factors in assessing the mechanism of injury of radiologically evident Salter-Harris (SH) fractures. The purpose of this study is to assess the frequency of posterior periosteal disruption on MRI in radiographically occult or subtle SH type II fractures of the distal femur and to evaluate associated soft-tissue findings that support a hyperextension mechanism of injury.
  
  
  CONCLUSIONS
  We found that all children in our experience with occult or subtle SH type II fractures of the distal femur have posterior periosteal disruption and other MRI findings to indicate a hyperextension mechanism of injury. Direct indicators of fracture may be inconspicuous, and the presence of posterior periosteal disruption is a clue that should prompt a search for other features of this serious pediatric injury, which may be followed by limb shortening or angular deformity.
authors.affiliation: Department of Radiology, Section of Musculoskeletal Imaging, Children's Hospital Boston and Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Supika
authors.initials: S
authors.lastname: Kritsaneepaiboon
authors.forename: Rajvee
authors.initials: R
authors.lastname: Shah
authors.forename: Martha M
authors.initials: MM
authors.lastname: Murray
authors.forename: Paul K
authors.initials: PK
authors.lastname: Kleinman
mesh_terms: D000293:Adolescent; D002648:Child; D005264:Femoral Fractures / Q000473:pathology*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D007718:Knee Injuries / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D010521:Periosteum / Q000293:injuries*; D012189:Retrospective Studies; D012307:Risk Factors