Computed tomography of normal distal tibiofibular syndesmosis.
OBJECTIVE
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).


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.


RESULTS
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.


CONCLUSIONS
This study provides measurements of the normal tibiofibular syndesmosis to aid in the diagnosis of occult diastasis.
Elgafy
Hossein
H
Department of Orthopaedic Surgery and Radiology, University of Toledo Medical Center, Dowling Hall 3065 University of Toledo Medical Center, Arlington Avenue, Toledo, OH 43614-5807, USA. helgafy@u.washington.edu
Semaan
Hassan B
HB
Blessinger
Brian
B
Wassef
Andrew
A
Ebraheim
Nabil A
NA
D000328:Adult; D000843:Ankle Joint / Q000000981:diagnostic imaging*; D005260:Female; D005360:Fibula / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D012016:Reference Values; D013977:Tibia / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods*