Related Experiment Video
Updated: Feb 14, 2026
Proximal Cadaveric Femur Preparation for Fracture Strength Testing and Quantitative CT-based Finite Element Analysis
Published on: March 11, 2017
Effect of Posterior Malleolus Fracture on Syndesmotic Reduction: A Cadaveric Study
Elizabeth Fitzpatrick1, Jessica E Goetz1, Tinnart Sittapairoj1
1University of Iowa Hospitals and Clinics, Iowa City, Iowa.
Background:
Syndesmotic malreduction and fractures of the posterior malleolus negatively influence outcomes of rotational ankle fractures. Recent data have shown that posterior malleolus fixation contributes to the stability of the syndesmosis. The purpose of this study was to analyze syndesmotic reduction within the context of different sizes of posterior malleolus fracture fragments and different qualities of reduction.
Methods:
A model of stage-IV supination-external rotation injury was created in 9 through-the-knee cadaveric specimens. The specimens were randomized to receive either a small (one-third of the incisura, n = 4) or a large (two-thirds of the incisura, n = 5) posterior malleolus fracture. High-resolution computed tomography (CT) scans were obtained of each intact specimen and then with clamp reduction of the syndesmosis along with a fracture fragment that was (1) unreduced, (2) anatomically reduced, or (3) fixed with a 4.8-mm-gap malreduction. Syndesmotic reduction in both the anterior-posterior and the medial-lateral direction was assessed relative to the intact specimen.
Results:
Clamp reduction of the syndesmosis increased medial translation of the distal part of the fibula in the specimens with an unfixed or an anatomically fixed posterior malleolus fracture fragment and caused lateral displacement of the distal part of the fibula in the specimens with gap malreduction of the posterior malleolus fracture. Clamp reduction of the syndesmosis caused a slight anterior shift of the fibula in the specimens with a small unfixed or anatomically fixed posterior malleolus fracture fragment and caused a posterior shift of the fibula in the specimens with gap malreduction of a large fragment.
Conclusions:
The overall anterior-posterior reduction of the syndesmosis was generally unaffected by a posterior malleolus fracture except when there was malreduction of a large fragment. Medial-lateral syndesmotic reduction was affected by the conditions of the posterior malleolus fixation, with malreduction of the posterior malleolus leading to syndesmotic malreduction.
Clinical Relevance:
When posterior malleolus fractures occur with syndesmotic injury, anatomic fracture reduction and fixation are paramount as they can affect syndesmotic reduction, especially with larger fragments.
More Related Videos
Related Concept Videos
03:11Oxidation-Reduction Reactions
01:27Fractures: Bone Repair
Minor fractures with no bone displacement are treated by immobilizing the fractured bone using a cast or splint. However, in the case of fractures with displaced bones, the broken bones are repositioned before immobilization to ensure successful healing without deformation and loss of function. The realignment of fractured bone ends is performed through a process called reduction. If the...
01:14Cranial Bones: Superior and Posterior View
The frontal bone is the single bone that forms the forehead. At its anterior midline, between the eyebrows, there is a slight depression called the glabella. The frontal bone also forms the supraorbital margin of the orbit. Near the middle of this margin is the supraorbital foramen, the opening that provides passage for a sensory nerve to the forehead. The frontal bone is thickened just above each supraorbital margin,...
02:36Oxymercuration-Reduction of Alkenes
01:22Block Diagram Reduction
The first step in this process is the identification and relocation of a branch point. A branch point, where a...
01:27Phase I Reactions: Reductive Reactions