Definitive treatment of suprasyndesmotic ankle injuries with a cast is rarely indicated .
However, if the facilities and the skill for safe operative treatment are not available, nonoperative treatment is safer, and if performed correctly and skillfully, it may lead to acceptable results.
In any situation, a displaced ankle fracture should be reduced as soon as possible, even if surgery is planned for the near future as this reduced pain and swelling.
If severe swelling is present, the reduced ankle fracture should be immobilized temporarily with a plaster of Paris (POP) back-slab, and elevated on several pillows.
In the absence of the facility for general anesthesia, reduction can be achieved under sedation (e.g., Pethidine plus Diazepam), and/or intraarticular local anesthesia (Lignocaine 2% 15ml).
The intraarticular injection of local anesthetic is introduced anteromedially, between the tendons of tibialis anterior and extensor hallucis longus, medial to the anterior tibial neurovascular bundle.
Suprasyndesmotic fractures result from external rotation of the talus in the ankle mortise with the foot in pronation (Lauge-Hansen pronation external rotation injuries) causing first a failure on the medial side (malleolar fracture or deltoid rupture). The talus then rotates forwards out of the mortise, disrupting the syndesmosis and applying a twisting force to the fibula which then fractures above the level of the syndesmosis.
The typical displacement in suprasyndesmotic fractures is lateral, usually with the foot externally rotated. Occasionally the foot displaces secondarily into a posterior displacement.
Careful review of the x-ray images is essential for a full understanding of the mechanism of injury.
Regard the injury as a two-part fracture between the lower leg (tibia and fibula) proximally, and the foot distally. The task will be to place the foot in correct alignment with the leg.
If x-rays are not available, it is safer to correct the deformity clinically, rather than to leave it unreduced.