title: MRI findings associated with distal tibiofibular syndesmosis injury.
abstract: OBJECTIVE
  Our objective was to describe the MRI findings associated with acute and chronic distal tibiofibular syndesmosis injury.
  
  
  METHODS
  Ninety-four 1.5-T MRIs of ankles of 90 individuals with histories of severe sprain were assessed by two musculoskeletal radiologists for syndesmosis injury (acute, edema of the syndesmosis; chronic, disruption or thickening of the syndesmosis without edema). We examined associated MRI findings, including anterior talofibular ligament injury (scar, chronic injury; edema, acute injury), bone bruise, osteochondral lesion, tibiofibular joint congruity, tibiofibular recess height, and osteoarthritis. The Fisher's exact test and analysis of variance test were used to evaluate the significance of the associations.
  
  
  RESULTS
  In 94 ankles, syndesmosis injury was seen in 63% (n = 59; 23 acute; 36 chronic). Anterior talofibular ligament injury (acute or chronic) was seen on MRIs in 74% (n = 70; 49 with syndesmosis injury; 21 without; p = 0.03). Bone bruises were present in 24% (n = 23; 18/23 acute; 4/36 chronic; 4/35 no injury; p < 0.0001). Of these, talar dome osteochondral lesions were present in 28% (n = 26; 11/23 acute; 14/36 chronic; 1/35 no injury; p = 0.0001; 13 medial; 13 lateral). The tibiofibular joint was incongruent in 33% (n = 31; 6/23 acute; 21/36 chronic; 4/35 no injury; p < 0.0001). The tibiofibular recess (mean +/- SD) was 1.2 +/- 0.92 cm in acute cases, 1.4 +/- 0.57 cm in chronic cases, and 0.54 +/- 0.68 cm in cases with no syndesmosis injury (p < 0.0001). Osteoarthritis was present in 10% (n = 9; 1/23 acute; 7/36 chronic; 1/35 no injury; p = 0.06).
  
  
  CONCLUSIONS
  Injury to the distal tibiofibular syndesmosis has a significant association with a number of secondary findings on MRI, including anterior talofibular ligament injury, bone bruises, osteochondral lesions, tibiofibular joint congruity, and height of the tibiofibular recess.
authors.affiliation: Department of Radiology, Thomas Jefferson University Hospital, 111 S 11th St., Ste. 3390, Gibbon Bldg., Philadelphia, PA 19107, USA.
authors.forename: Kevin W
authors.initials: KW
authors.lastname: Brown
authors.forename: William B
authors.initials: WB
authors.lastname: Morrison
authors.forename: Mark E
authors.initials: ME
authors.lastname: Schweitzer
authors.forename: J Antoni
authors.initials: JA
authors.lastname: Parellada
authors.forename: Henry
authors.initials: H
authors.lastname: Nothnagel
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D016512:Ankle Injuries / Q000150:complications / Q000473:pathology*; D002648:Child; D002908:Chronic Disease; D005260:Female; D006801:Humans; D008023:Ligaments, Articular / Q000293:injuries* / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013180:Sprains and Strains / Q000150:complications / Q000473:pathology*