title: Comparison of bone contusion seen by MRI in partial and complete tears of the anterior cruciate ligament.
abstract: OBJECTIVE
  Bone contusions are frequently found in association with complete tears of the anterior cruciate ligament (ACL) and can be a helpful secondary sign in diagnosis. We compare the frequency, location, and significance of bone contusions in complete and partial ACL tears.
  
  
  METHODS
  Twenty-nine patients with complete and 42 patients with incomplete tears of the ACL were examined by MRI for the presence of accompanying bone contusions within 1 month of injury.
  
  
  RESULTS
  Bone contusions were found in 72% of the complete ACL tears but in only 12% of the partial tears. Of the partial ACL tears with accompanying contusions, 80% were high grade injuries that eventually went on to complete rupture within 6 months. Only 16% of the partial ACL injuries without bone contusion progressed to complete rupture at 1-2 year follow-up. There was no difference between the bone contusions of partial and complete tears in terms of general appearance and location. They were predominantly in the lateral compartment (90%) and had a specific predilection for the mid portion of the lateral femoral condyle and the posterior portion of the lateral tibial plateau, often occurring in tandem.
  
  
  CONCLUSIONS
  Bone contusions occur with much less frequency in partial ACL tears than in complete tears but their presence in partial rupture favors a high grade tear that is likely to become complete.
authors.affiliation: Department of Radiology, Medical College of Ohio, Toledo 43699-0008, USA.
authors.forename: J
authors.initials: J
authors.lastname: Zeiss
authors.forename: K
authors.initials: K
authors.lastname: Paley
authors.forename: K
authors.initials: K
authors.lastname: Murray
authors.forename: S R
authors.initials: SR
authors.lastname: Saddemi
mesh_terms: D000293:Adolescent; D000328:Adult; D016118:Anterior Cruciate Ligament / Q000473:pathology; D000070598:Anterior Cruciate Ligament Injuries; D001182:Arthroscopy; D003288:Contusions / Q000175:diagnosis* / Q000473:pathology; D018450:Disease Progression; D005260:Female; D005269:Femur / Q000293:injuries / Q000473:pathology; D005500:Follow-Up Studies; D006801:Humans; D007718:Knee Injuries / Q000175:diagnosis* / Q000473:pathology; D007719:Knee Joint / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D012399:Rotation; D012421:Rupture; D013977:Tibia / Q000293:injuries / Q000473:pathology