title: Ultrasound of displaced ulnar collateral ligament tears of the thumb: the Stener lesion revisited.
abstract: OBJECTIVE
  To retrospectively characterize the ultrasound appearance of displaced ulnar collateral ligament (UCL) tears that are proven at surgery, and then determine the accuracy of the resulting ultrasound criteria in differentiating displaced from non-displaced UCL tears.
  
  
  METHODS
  After institutional review board approval, 26 patients were identified from the radiology information system over a 10-year period that had ultrasound evaluation of the thumb and surgically proven UCL tear. Retrospective review of the displaced full-thickness tears was carried out to characterize displaced tears and to establish ultrasound criteria for such tears. A repeat retrospective review 4 months later of all UCL tears applied the criteria to determine accuracy of ultrasound in the diagnosis of displaced full-thickness UCL tear.
  
  
  RESULTS
  The 26 subjects consisted of 17 displaced full-thickness UCL tears, seven non-displaced full-thickness tears, and two partial-thickness tears at surgery. Retrospective ultrasound review of displaced full-thickness tears identified two criteria present in all cases: non-visualization of the UCL ligament and presence of a heterogeneous mass-like area proximal to the first metacarpophalangeal joint. Applying these criteria at the second retrospective review resulted in 100 % sensitivity, specificity, positive predictive value, negative predictive value, and accuracy.
  
  
  CONCLUSIONS
  The ultrasound findings of absent UCL fibers and presence of a heterogeneous mass-like abnormality proximal to the first metacarpophalangeal joint achieved 100 % accuracy in differentiating displaced from non-displaced full-thickness UCL tear of the thumb. Displaced full-thickness UCL tears most commonly were located proximal to the adductor aponeurosis.
authors.affiliation: Department of Radiology, University of Michigan, Ann Arbor, MI 48109-0326, USA.
authors.forename: David
authors.initials: D
authors.lastname: Melville
authors.forename: Jon A
authors.initials: JA
authors.lastname: Jacobson
authors.forename: Steven
authors.initials: S
authors.lastname: Haase
authors.forename: Catherine
authors.initials: C
authors.lastname: Brandon
authors.forename: Monica Kalume
authors.initials: MK
authors.lastname: Brigido
authors.forename: David
authors.initials: D
authors.lastname: Fessell
mesh_terms: D000328:Adult; D000368:Aged; D017885:Collateral Ligaments / Q000000981:diagnostic imaging* / Q000293:injuries*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013933:Thumb / Q000293:injuries*; D014463:Ultrasonography; D055815:Young Adult