- Discussion:
- pronation of forefoot is combination of external rotation at ankle, abduction of hindfoot, & eversion of forefoot;
- in pronation, the medial structures tighten and are injured first;
- pronation of forefoot is combination of external rotation at ankle, abduction of hindfoot, & eversion of forefoot;
- in pronation, the medial structures tighten and are injured first;
- Sequence of Injury:
- avulsion frx of medial malleolus or rupture of deltoid ligament;
- malleolus will have a transverse frx;
- abduction force then either ruptures syndesmotic ligaments or avulses their bony attachment sites;
- lateral force from talus impacts and fractures fibula at or above level of syndesmosis & ruptures interosseous membrane up to level of this frx;
- fracture is either oblique or partially transverse;
- occasionally has a butterfly fragment, making it unstable;
- Associated Injuries:
- dome fractures of the talus are common in this shearing fracture
Results of operative treatment of displaced external rotation-abduction fractures of the ankle.