title: Imaging findings in symptomatic patients with femoral diaphyseal stress injuries.
abstract: OBJECTIVE
  To assess the imaging findings seen in symptomatic patients with stress injuries of the femoral diaphysis.
  
  
  METHODS
  Seven patients (5 F, 2 M, age range 16 to 56 years, mean 38 years) underwent imaging evaluation of the symptomatic lower extremity due to an insidious onset of thigh or groin pain unrelated to trauma. Imaging studies included radiography and magnetic resonance imaging (MRI) in seven patients, bone scintigraphy in five, and computed tomography (CT) in three.
  
  
  RESULTS
  Radiographs depicted three frank fractures in two patients, and revealed findings of stress injury in six patients. Available scintigraphic and CT findings were abnormal. On MR images, a solitary fracture was seen in two patients; two patients presented with bilateral stress fractures of the femoral diaphysis; and all seven patients had the imaging features of stress injury. Femoral diaphyseal stress fractures (n = 6) appeared as linear regions of T1- and T2-weighted low signal intensity, surrounded by diffuse bone marrow edema. Three of the six frank fractures, with an evident fracture line, were longitudinal and parallel to the cortical surface.
  
  
  CONCLUSIONS
  Femoral diaphyseal stress fractures are often inconspicuous with conventional radiography. MRI depicts the changes of stress injury in the femoral diaphysis, and is particularly useful in documenting the presence, morphology, and extent of fracture(s), information valuable for definitive diagnosis and appropriate management.
authors.affiliation: Department of Radiology, School of Medicine, University of California, San Diego Medical Center, San Diego, Calif, USA. rjtheodorou@hotmail.com
authors.forename: S J
authors.initials: SJ
authors.lastname: Theodorou
authors.forename: D J
authors.initials: DJ
authors.lastname: Theodorou
authors.forename: D
authors.initials: D
authors.lastname: Resnick
mesh_terms: D000293:Adolescent; D000328:Adult; D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D005264:Femoral Fractures / Q000175:diagnosis* / Q000188:drug therapy; D005269:Femur / Q000000981:diagnostic imaging / Q000473:pathology; D005500:Follow-Up Studies; D015775:Fractures, Stress / Q000175:diagnosis* / Q000188:drug therapy; D019786:Gadolinium DTPA; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D010146:Pain / Q000209:etiology; D011877:Radionuclide Imaging; D035583:Rare Diseases; D014057:Tomography, X-Ray Computed / Q000379:methods
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA