title: Radial collateral ligament of the elbow: sonographic characterization with cadaveric dissection correlation and magnetic resonance arthrography.
abstract: OBJECTIVE
  An abnormality of the radial collateral ligament (RCL) in the setting of lateral epicondylitis can indicate a poor clinical outcome; therefore, accurate assessment is important. The purpose of this study was to characterize the proximal RCL attachment, or footprint, as seen on sonography using cadaveric dissection correlation and magnetic resonance arthrography.
  
  
  METHODS
  For the first part of this study, 4 cadaveric elbow specimens were imaged with sonography before and after dissection to characterize the RCL. After Institutional Review Board approval with consent waived, 26 consecutive magnetic resonance (MR) arthrograms of the elbow were identified. The sonograms and MR arthrograms were retrospectively reviewed to measure the length of the RCL footprint and its percentage of the combined RCL and common extensor tendon (CET) humeral footprints.
  
  
  RESULTS
  The mean RCL footprint length and percentage of the combined RCL and CET footprints were 8.4 mm (range, 7.4-10.0 mm) and 54% as measured from the elbow specimen sonograms and 9.1 mm (range, 6.4-12.5 mm) and 54% as measured from the MR arthrograms. The mean RCL footprint length combining data from specimens and MR arthrograms was 8.9 mm (range, 6.4-12.5 mm), covering 54% of the combined RCL and CET footprints.
  
  
  CONCLUSIONS
  The RCL can be differentiated from the CET on sonography with knowledge of the RCL humeral footprint extent, which measured 8.9 mm in length and comprised 54% of the combined RCL and CET footprints.
authors.affiliation: Departments of Radiology (J.A.J., B.D., C.M.Y.) and Orthopedic Surgery (J.M.L., J.L.), University of Michigan, Ann Arbor, Michigan USA; and Department of Diagnostic Imaging, McMaster University, Hamilton General Hospital, Hamilton, Ontario, Canada. jjacobsn@umich.edu.
authors.forename: Jon A
authors.initials: JA
authors.lastname: Jacobson
authors.affiliation: Departments of Radiology (J.A.J., B.D., C.M.Y.) and Orthopedic Surgery (J.M.L., J.L.), University of Michigan, Ann Arbor, Michigan USA; and Department of Diagnostic Imaging, McMaster University, Hamilton General Hospital, Hamilton, Ontario, Canada.
authors.forename: Mary M
authors.initials: MM
authors.lastname: Chiavaras
authors.affiliation: Departments of Radiology (J.A.J., B.D., C.M.Y.) and Orthopedic Surgery (J.M.L., J.L.), University of Michigan, Ann Arbor, Michigan USA; and Department of Diagnostic Imaging, McMaster University, Hamilton General Hospital, Hamilton, Ontario, Canada.
authors.forename: Jason Michael
authors.initials: JM
authors.lastname: Lawton
authors.affiliation: Departments of Radiology (J.A.J., B.D., C.M.Y.) and Orthopedic Surgery (J.M.L., J.L.), University of Michigan, Ann Arbor, Michigan USA; and Department of Diagnostic Imaging, McMaster University, Hamilton General Hospital, Hamilton, Ontario, Canada.
authors.forename: Brian
authors.initials: B
authors.lastname: Downie
authors.affiliation: Departments of Radiology (J.A.J., B.D., C.M.Y.) and Orthopedic Surgery (J.M.L., J.L.), University of Michigan, Ann Arbor, Michigan USA; and Department of Diagnostic Imaging, McMaster University, Hamilton General Hospital, Hamilton, Ontario, Canada.
authors.forename: Corrie M
authors.initials: CM
authors.lastname: Yablon
authors.affiliation: Departments of Radiology (J.A.J., B.D., C.M.Y.) and Orthopedic Surgery (J.M.L., J.L.), University of Michigan, Ann Arbor, Michigan USA; and Department of Diagnostic Imaging, McMaster University, Hamilton General Hospital, Hamilton, Ontario, Canada.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Lawton
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001175:Arthrography / Q000379:methods; D002102:Cadaver; D004210:Dissection; D004551:Elbow Joint / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D006811:Humerus / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D008023:Ligaments, Articular / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011884:Radius / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014463:Ultrasonography / Q000379:methods*
keywords: common extensor tendon; elbow; magnetic resonance arthrography; magnetic resonance imaging; musculoskeletal ultrasound; radial collateral ligament; sonography