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The Syndesmosis, Part I: Anatomy, Injury Mechanism, Classification, and Diagnosis
Lorena Bejarano-Pineda1, Daniel Guss1, Gregory Waryasz1
1Foot & Ankle Research and Innovation Laboratory - Harvard Medical School, Division of Foot and Ankle Surgery, Department of Orthopaedic Surgery, Massachusetts General Hospital - Newton-Wellesley Hospital, 40 2nd Avenue Building 52, Suite 1150, Waltham, MA 02451, USA; Foot & Ankle Service, Department of Orthopaedic Surgery, Massachusetts General Hospital, 40 2nd Avenue Building 52, Suite 1150, Waltham, MA 02451, USA.
Abstract:
Ankle fractures are common injuries to the lower extremity with approximately 20% sustaining a concomitant injury to the syndesmosis. Although the deltoid ligament is not formally included in the syndesmotic complex, it plays an important role in the mortise stability. Therefore, its integrity should be always evaluated when syndesmotic injury is suspected. Given the anatomic variability of the syndesmosis between individuals, bilateral ankle imaging is recommended, especially in cases of subtle instability. Diagnostic tests that allow dynamic assessment of the distal tibiofibular joint in the 3 planes are the most reliable in determining the presence of syndesmotic injury.
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