title: Injuries to the distal gastrocnemius muscle: MR findings.
abstract: OBJECTIVE
  The purpose of this work was to demonstrate the MR findings of injuries to the distal gastrocnemius muscle.
  
  
  METHODS
  Twenty patients with clinically confirmed injuries to the distal gastrocnemius muscle underwent MRI. The injuries were evaluated with regard to abnormal morphology or signal abnormality, site, and degree of tearing.
  
  
  RESULTS
  Twenty-three injuries to the distal gastrocnemius occurred in 20 patients, with involvement of the myotendinous junction in 22 of 23 (96%) injuries. An interstitial tear of the proximal Achilles tendon was present in one instance. Myotendinous strains were the most common injuries (10/23; 43%); partial tears (7/23; 30%) and complete tears (5/23; 22%) of the myotendinous junction or proximal Achilles tendon were less frequent. When an injury to the gastrocnemius myotendinous junction was present, involvement of the medial head (19/22; 86%) was more frequent than involvement of the lateral head (3/22; 14%).
  
  
  CONCLUSIONS
  MRI allows accurate imaging of distal gastrocnemius muscle injuries. When occurring, distal gastrocnemius muscle injuries most frequently involve the myotendinous junction of the medial gastrocnemius head and occasionally the lateral gastrocnemius head or the proximal Achilles tendon.
authors.affiliation: Institute of Diagnostic Radiology, University Hospital, Zurich, Switzerland. dominik.weishaupt@dmr.usz.ch
authors.forename: D
authors.initials: D
authors.lastname: Weishaupt
authors.forename: M E
authors.initials: ME
authors.lastname: Schweitzer
authors.forename: W B
authors.initials: WB
authors.lastname: Morrison
mesh_terms: D000125:Achilles Tendon / Q000293:injuries*; D000293:Adolescent; D000328:Adult; D000368:Aged; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007866:Leg / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000293:injuries* / Q000473:pathology; D012720:Severity of Illness Index