title: 3-T direct MR arthrography of the wrist: value of finger trap distraction to assess intrinsic ligament and triangular fibrocartilage complex tears.
abstract: OBJECTIVE
  To determine the value of applying finger trap distraction during direct MR arthrography of the wrist to assess intrinsic ligament and triangular fibrocartilage complex (TFCC) tears.
  
  
  METHODS
  Twenty consecutive patients were prospectively investigated by three-compartment wrist MR arthrography. Imaging was performed with 3-T scanners using a three-dimensional isotropic (0.4 mm) T1-weighted gradient-recalled echo sequence, with and without finger trap distraction (4 kg). In a blind and independent fashion, two musculoskeletal radiologists measured the width of the scapholunate (SL), lunotriquetral (LT) and ulna-TFC (UTFC) joint spaces. They evaluated the amount of contrast medium within these spaces using a four-point scale, and assessed SL, LT and TFCC tears, as well as the disruption of Gilula's carpal arcs.
  
  
  RESULTS
  With finger trap distraction, both readers found a significant increase in width of the SL space (mean Δ = +0.1mm, p ≤ 0.040), and noticed more contrast medium therein (p ≤ 0.035). In contrast, the differences in width of the LT (mean Δ = +0.1 mm, p ≥ 0.057) and UTFC (mean Δ = 0mm, p ≥ 0.728) spaces, as well as the amount of contrast material within these spaces were not statistically significant (p = 0.607 and ≥ 0.157, respectively). Both readers detected more SL (Δ = +1, p = 0.157) and LT (Δ = +2, p = 0.223) tears, although statistical significance was not reached, and Gilula's carpal arcs were more frequently disrupted during finger trap distraction (Δ = +5, p = 0.025).
  
  
  CONCLUSIONS
  The application of finger trap distraction during direct wrist MR arthrography may enhance both detection and characterisation of SL and LT ligament tears by widening the SL space and increasing the amount of contrast within the SL and LT joint spaces.
authors.affiliation: Department of Diagnostic and Interventional Radiology, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Rue du Bugnon 46, 1011 Lausanne, Switzerland.
authors.forename: Milena
authors.initials: M
authors.lastname: Cerny
authors.forename: Romain
authors.initials: R
authors.lastname: Marlois
authors.forename: Nicolas
authors.initials: N
authors.lastname: Theumann
authors.forename: Christof
authors.initials: C
authors.lastname: Bollmann
authors.forename: Laurent
authors.initials: L
authors.lastname: Wehrli
authors.forename: Delphine
authors.initials: D
authors.lastname: Richarme
authors.forename: Reto
authors.initials: R
authors.lastname: Meuli
authors.forename: Fabio
authors.initials: F
authors.lastname: Becce
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D005385:Fingers / Q000473:pathology; D050724:Fractures, Cartilage / Q000473:pathology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D056888:Patient Positioning / Q000379:methods*; D015203:Reproducibility of Results; D012421:Rupture / Q000473:pathology; D012680:Sensitivity and Specificity; D051478:Triangular Fibrocartilage / Q000293:injuries* / Q000473:pathology*; D014954:Wrist Injuries / Q000473:pathology*; D055815:Young Adult
keywords: Articular distraction; Intrinsic ligaments; Magnetic resonance arthrography; Triangular fibrocartilage complex; Wrist