Skeletal Radiology

, Volume 39, Issue 6, pp 559–564 | Cite as

Computed tomography of normal distal tibiofibular syndesmosis

  • Hossein ElgafyEmail author
  • Hassan B. Semaan
  • Brian Blessinger
  • Andrew Wassef
  • Nabil A. Ebraheim
Scientific Article



The purpose of this study was to determine the shape and measurements of the normal distal tibiofibular syndesmosis on computed tomographic scans and to identify features that could aid in the diagnosis of syndesmotic diastasis using computed tomography (CT).

Materials and methods

CT scans of 100 patients with normal distal tibiofibular syndesmoses were reviewed retrospectively. In 67% the incisura fibularis was deep, giving the syndesmosis a crescent shape. In 33% the incisura fibularis was shallow, giving the syndesmosis a rectangular shape. The measurements of both types were taken using the same reference points.


The mean age of the patients was 40 years, and there were 53 men and 47 women. The mean width of the distal tibiofibular syndesmosis anteriorly between the tip of the anterior tibial tubercle and the nearest point of the fibula was 2 mm. The mean width of the distal tibiofibular syndesmosis posteriorly between the medial border of the fibula and the nearest point of the lateral border of the posterior tibial tubercle was 4 mm. In men the mean width of the distal tibiofibular syndesmosis, anterior and posterior, was 2 mm and 5 mm, respectively, and in women it was 2 mm and 4 mm, respectively.


This study provides measurements of the normal tibiofibular syndesmosis to aid in the diagnosis of occult diastasis.


Ankle Syndesmosis Syndesmotic Injury Tibia Fibula Diastasis Syndesmotic injury 


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Copyright information

© ISS 2009

Authors and Affiliations

  • Hossein Elgafy
    • 1
    Email author
  • Hassan B. Semaan
    • 1
  • Brian Blessinger
    • 1
  • Andrew Wassef
    • 1
  • Nabil A. Ebraheim
    • 1
  1. 1.Departments of Orthopaedic Surgery and RadiologyUniversity of Toledo Medical CenterToledoUSA

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