title: Articular muscle of the knee: a muscle seldom recognized on MR imaging.
abstract: OBJECTIVE
  We studied the MR imaging characteristics of the articular muscle of the knee, an important but seldom recognized structure of the distal thigh and knee.
  
  
  METHODS
  We used a 1.5-T system to prospectively evaluate the articular muscle of the knee in five healthy volunteers (10 knees); then we retrospectively studied the knee examinations of 24 patients (30 knees). One reader made duplicate readings to prospectively assess the sagittal proton density-weighted and axial T1-weighted images of the healthy volunteers. Three independent readers retrospectively evaluated the sagittal proton density-weighted images of the 24 patients.
  
  
  RESULTS
  The articular muscle of the knee was identified in 100% of prospective studies (10/10) and in 83% of retrospective studies (25/30). For the prospective study group, measurements (mean +/- SEM) were as follows: number of bundles, 2.4 +/- 0.68 (range, 1-4); length of uppermost bundle, 47.2 +/- 4.06 mm; width of origin, 8.6 +/- 0.79 mm; angle of origin, 11.4 degree +/- 1.29 degree; and cross-sectional bundle width, 19.8 +/- 2.05 mm2.
  
  
  CONCLUSIONS
  The articular muscle of the knee can usually be identified by MR imaging as an independent entity, separate from the great (vastus) muscle group.
authors.affiliation: Universitätsklinik für Radiodiagnostik, Vienna, Austria.
authors.forename: S
authors.initials: S
authors.lastname: Puig
authors.forename: D E
authors.initials: DE
authors.lastname: Dupuy
authors.forename: A
authors.initials: A
authors.lastname: Sarmiento
authors.forename: G W
authors.initials: GW
authors.lastname: Boland
authors.forename: P
authors.initials: P
authors.lastname: Grigoris
authors.forename: R
authors.initials: R
authors.lastname: Greene
mesh_terms: D000293:Adolescent; D000328:Adult; D000070598:Anterior Cruciate Ligament Injuries; D005260:Female; D006801:Humans; D007717:Knee / Q000033:anatomy & histology* / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000033:anatomy & histology* / Q000473:pathology; D011446:Prospective Studies; D012016:Reference Values; D012189:Retrospective Studies; D000070600:Tibial Meniscus Injuries