title: Ultrasonographic test for complete anterior cruciate ligament injury.
abstract: BACKGROUND
  Although ultrasound (US) has a wide range of applications in orthopedic diagnostics, sonographic evaluation of traumatic anterior cruciate ligament (ACL) insufficiency is still inadequate. There is a growing need for diagnostic tests that allow for simple and reliable assessment of ACL instability. This investigation aims to evaluate feasibility of sonographic technique for diagnosing complete ACL insufficiency.
  
  
  METHODS
  Eighty three consecutive patients suspected of ACL injury were examined with sonographic, dynamic test of anterior instability. The translation of the intercondylar eminence against the patellar tendon was measured in the injured and opposite (injured) knee. Subsequent magnetic resonance imaging was performed on all patients. Forty-seven of them underwent a further arthroscopy. Five patients have been examined for the 2(nd) time to evaluate interclass and intraclass agreement and bias.
  
  
  RESULTS
  Complete ACL insufficiency has been confirmed in 37 patients. In those individuals, the total anterior knee translation and the difference between two joints (side-to-side difference) were significantly increased (8.67 mm standard deviation [SD] 2.65 mm in the affected knee versus 2.88 mm SD 1.26 mm in uninjured joint; P < 0.001). Based on a threshold of 2.0 mm for the side-to-side difference and 5.0 mm for the absolute translation, the sonographic test was found to have a sensitivity and specificity of 91.9% and 95.6%, respectively.
  
  
  CONCLUSIONS
  The present technique supports the clinician with additional fast and noninvasive diagnostic procedure that can facilitate the evaluation of anterior knee instability.
authors.affiliation: Departments of Radiology Imaging Diagnostic and Orthopedics, Medical University of Lodz, Lodz, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Grzelak
authors.affiliation: Departments of Radiology Imaging Diagnostic and Orthopedics, Medical University of Lodz, Lodz, Poland.
authors.forename: Michał Tomasz
authors.initials: MT
authors.lastname: Podgórski
authors.affiliation: Departments of Radiology Imaging Diagnostic and Orthopedics, Medical University of Lodz, Lodz, Poland.
authors.forename: Ludomir
authors.initials: L
authors.lastname: Stefańczyk
authors.affiliation: Department of Orthopedics, Medical University of Lodz, Lodz, Poland.
authors.forename: Marcin
authors.initials: M
authors.lastname: Domżalski
keywords: Anterior cruciate ligament; Anterior cruciate ligament injury; anterior tibial translation; arthroscopy; ultrasonography